Thursday, September 3, 2020
Assessing Strategic Analysis About Ryanair Airways
Evaluating Strategic Analysis About Ryanair Airways The Ryanair is begun by the Ryan family in 1985, with share capital of one pound and just with 25 associates , they began consistent schedule departures from Waterford in the Ireland to London Gatwick, with 5000 travelers on the course . The organization become further with high contenders British Airways and air Lingus . It is working in an exceptionally serious areas . in any case, following 3 years of quick mechanical development , organization progressively got the quantities of travelers. with the cost and courses rivalry they face à £20mn misfortunes and it drives pondering rebuilding , Ryanair was take models from southwest aircrafts minimal effort administration model .Under the new supervisory crew with new CEO Michael Oââ¬â¢Leary reconsider and Launch a New LOW COST , NO FRILLS Strategy . In 1997 the EU Air transport authority permits the Ryanair to first an ideal opportunity to work 18 new courses in European Continental zone. They made numerous restorative move agains t cost decrease Eg no free beverages ,nourishments, and different offices. Ryanair got great reaction from every European traveler who preferences visit , speedy and Low cost Travel . Ryanair overwhelms BA and Air Lingus in the Dublin â⬠London courses . Ryanair accomplishes their goal in a brief period , they won numerous honors and positions in aircrafts industry, Ryanair got great name for promptness. reliably the association extends tasks , in this way in become celebrated carrier on the planet ., and right now Ryanair working 24 nations 436 low admission defeats conveyed close by 60mn individuals . Ryanairââ¬â¢s Strategy : ââ¬Å"Ryanairââ¬â¢s objective is to immovably build up itself as Europeââ¬â¢s driving low-admissions planned traveler aircraft through proceeded with enhancements and extended contributions of its low-passages serviceâ⬠(Ryanair.com)The Ryanair key systems. Industry Leading traveler administration High recurrence on short-pull courses. Fundam entally offering an assistance with Low tolls . â⬠low working costs, tending to airplane and hardware, staff profitability, client assistance expenses and air terminal access charges Use the web adequately Commitment to the wellbeing and quality upkeep . Grow the activity results by means of Ancillary administrations. Ryanair offering an exceptionally separated item with very lower admission, which expanding their upper hand to keep up serious situation on over its rival. The firm makes to promise to their market territory by stamping Europeââ¬â¢s first no nonsense carrier service.(Ryanair.com). Supportable upper hand : Cost decrease Strategy: The Ryanair has following cost decrease technique for accomplishing its objective for holding their serious situation in carriers enterprises . there is five fundamental useful elements like Airport charges , contracting out administrations , armada shared trait , oversaw staff expenses and showcasing cost .these are the territories the y are giving extraordinary concentration to improve minimal effort activity . As per armada shared characteristic the aviation routes utilizing specific kind of airplane which controls the expense and constrains the expense for worker preparing and improvement , support cost and overseeing saves , giving greater adaptability to booking the obligation group and airplane. The Ryanair utilizing Boeing 737 arrangement to work more quantities of travelers, and it permits 25% of expanded their travelers with ensured 15 years of working life .the old armada took more support coat and less eco-friendly , as indicated by EU commotion decrease necessities, the Ryanair armadas are required to introduce hushkits to dodge clamors , it take more expense for establishment nearly $20mn , the expanded weight may leads by negative figure of eco-friendliness .
Tuesday, August 25, 2020
American Indian Conjuring
Conjuring is supposed to be the second-most established calling on the planet, and likely could be the most established of the showy expressions. It was the painstakingly protected weapon of the organization used to build up a confidence in heavenly powers among a clueless open (Randi, 1992, p. XI). The word reference characterizes a conjuror as ââ¬Å"a individual who rehearses legerdemain [sleight of hand]; jugglerââ¬Å". (Websterââ¬â¢s College Dictionary, 1992, p. 281). Another source characterizes conjuring as the craft of ââ¬Å"producing the presence of real enchantment by methods for craftiness and deceptionâ⬠(Randi, 1992, p. XI). Any individual who went to Sunday school as a youngster can review the scriptural record of Aaronââ¬â¢s fight with two magicians in Pharosââ¬â¢s court. In the story, every one of the magi cast down bars that became snakes. The key to the stunt was the snakes had been sedated or spellbound which made them look like sticks, at that point became versatile when stroked by the conjurors (Randi, 1992, p. 1). Eunios, a Syrian, halted an insubordination of Sicilian slaves around 135 B. C. with his wonderment inciting fire relaxing. He asserted a Syrian goddess had made him safe to fire. Florus, the recorder, had different thoughts. He demanded that Eunios had the blazing substance discharged in nutshells in his mouth (Christopher, 1962, p. 6). In 1865 Robert Houdin, a French performer and clock producer, forestalled a defiance in Algeria with legerdemain. The French government requested that the performer ruin the Marabouts, an Arab strict group who were utilizing enchantment to actuate a resistance. He demonstrated his fantasies were more impressive than the enchantment of the Marabouts, hence halting discuss insubordination (Magic History n. d. ). The line among regular and powerful is frequently ineffectively drawn. Among the American Indian individuals, skillful deception accomplishments, basic deceives, and snake enchanting were contributed with otherworldly centrality during ancestral customs. Witch specialists and medication men utilized the gadgets of performers to expand their notoriety and impact (Christopher, 1962, p. 6). In this work, I will examine the different methods American Indian shamans utilized to misdirect the individuals into deduction they had heavenly powers. I will at that point uncover their techniques for prestidigitation and finish up with an assessment of the loss of the workmanship. Despite the fact that American Indian hamans for quite a long time had frequently coordinated and outperformed the undeniably more generally known fakirs of Calcutta and Bombay, barely any anecdotes about their ability showed up in either the national or the universal press, and this for a sound explanation: The Asian seers, praised by voyagers, acted out in the open for the cash the could gather from their side of the road appears. The American Indianââ¬â¢s enchantment was held for their clan; barely any white men had a chance to consider it. On the off chance that an uncommon pariah tumbled on to a mystery, he was quickly enlisted as kindred spirit and vowed to mystery (Christopher, 1973, p. 69). Native American shamans were at their best in the outdoors under the night sky. At the point when tom-toms beat and open air fires cast gleaming shadows, their abnormal accomplishments were remarkable to individual tribesmen as the infrequent flashes of lightning that streaked over the sky. The Navajo, similar to their partners in India, caused snakes to show up under modified containers. Pawnee, Hopi, and Zuni shamans caused corn and beanstalks to develop (mango trees were not accessible) during harvest customs. The accomplishment where a Hindu conjurerââ¬Ës partner evaporated and returned in a huge crate was additionally done by the Apaches. Blades were poked through the sides to demonstrate that nobody was inside in Asia; the Apaches had a progressively compelling contention; they shot bolts through the strands (Christopher, 1973, p. 69). In 1871, John Wesley Powell, a geologist and delegate of the United States Bureau of Ethnology saw a show of the expertise of Cramped Hand and Bent Horn, two Ponca shamans. ââ¬Å"One evening, close to nightfall, around 200 people, for the most part Indians, remained in an enormous hover around a tent where sat the shamans and their aides. Directly the shamans and the matured boss, Antoine Primeau, came out of the tent and remained inside the circle. One of the shamans, Cramped Hand, moved along the internal side of the circle, displaying a gun (Allenââ¬â¢s patent), one office of which he appeared to stack as the individuals looked on. After he had put on the top, he gave the weapon to the boss, who discharged at the shaman. Squeezed Hand fell promptly, as though severely injured. Bowed Horn raced to his help and started to control him. It was not to some time before Cramped Hand had the option to creep around on all fours, however the slug had clearly hit him in the mouth. He moaned and hacked up unremittingly, and after a tin bowl was put down before him he hacked up a shot which fell in the bowl, and was appeared in triumph to the crowdâ⬠(Powell, 1894, p. 417). The exhibit was stunning, however unreasonable in fight. This was generally finished with a genuine weapon and a gaffed round, the projectile having been supplanted with a wax throwing. The blast of the charge and drive of the phony shot through the air successfully disintegrated the wax inside a short separation. The wax slug can be made to look like lead by covering it with a dark substance (Bagai, n. d. ). Squeezed Hand had distinctly to mystery an indistinguishable projectile in his mouth during the falling activity, the rest was acting. A lot of what we think about the enchantment rehearsed by the main Americans originates from ministers who worked among the Indians in the years when the New World was being colonized by Europeans. French clerics revealed from Canada in 1613 that the medication men of the Algonquin clans were the most impressive adversaries they looked in attempting to change over the Indians. After twenty years Gabriel Sagard-Theodat, a Recollect evangelist, exhausted of the every day strife with individuals whose traditions he didn't comprehend, called the Nipissing redmen ââ¬Å"a country of sorcerersâ⬠(Christopher, 1973, p. 70) There is an entrancing depiction of a stunt by Fray Bernardio de Sahagu in his Historia de las Cosa de la Nueva Espana: ââ¬Å"Seating himself in the commercial center at Tianquiztli, he reported that his name was Tlacavepan, and continued to make little figures move in the palms of his hands. â⬠No one who saw the stunt could offer an answer. There is anyway a basic clarification: the little figures were controlled by strands of long hair (like current entertainers imperceptible string) integrated and appended to the sorcerers feet. All he needed to do was squirm his toe and the figures became animated (Gosh, 2006, p. 21). Legends state that the early medication men could bring smaller than normal pictures of wild ox and warriors riding a horse to life. They worked by the glimmering light of a fire at the furthest side of the tent with onlookers assembled in a half circle. At the order of the performer, the earth figures should have changed to fragile living creature and blood. At that point the smaller than expected Indians corralled the bison and heaved their lances and shot their bolts with savage exactness until the last creature fell with a bolt through its heart. At the point when the dramatization finished, the figures returned to dirt and were hurled into the fire. Only occasionally has a manikin show got such applause. Whoever began the story more likely than not guzzled too uninhibitedly before going to the presentation (Christopher, 1973, p. 75). Shamans of the clans who lived along the St. Lawrence River flaunted they could call the downpours or stop storms. They asserted their customs could render fields desolate or produce abundant yields ( Christopher, 1973, p. 0) The Franciscan monk, Louis Hennepin said of the shamans: It is difficult to envision the appalling wailing and abnormal twistings that these performers make of their bodies, when they are dismissing themselves to invoke, or raise their enchantmentsâ⬠(Hennepin, 1869, p. 59). Pa ul Beaulieu, a translator for the Ojibwa at White Earth Agency, Minnesota (First settlement by white individuals, n. d. ), heard stories of Indian slick people the 1850ââ¬â¢s. At Leech Lake, Minnesota he saw an Indian shaman clad in a breechcloth tied by a board of trustees of twelve men. The shamanââ¬â¢s lower legs, wrists and hands were bound; his secured hands were constrained with the goal that his knees reached out up above them. A substantial shaft was pushed over his arms and under his knees; at that point his neck was attached to the knees and he was conveyed into a tent. The structure was based on shafts, entwined with twigs, and secured with segments of birch and canvas (Christopher, 1973, p. 74). The fold had barely been shut when abnormal words and pounding sounds originated from inside. The tent influenced viciously as the sounds expanded in volume. At the point when the aggravation stopped, the Indian yelled that the rope could now be found in a close by house. Forewarning the advisory group to keep a sharp watch on the tent, Beaulieu ran to the house. The rope was there, still tied. He rushed back, let different men look at the bunches, and afterward called to inquire as to whether he could enter. Authorization was allowed and he found the Indian situated serenely, puffing on a funnel (Christopher, 1973, p. 74). No clarification was offered for the shocking accomplishment. There is in any case, a way it could have been done, a strategy so evident that Beaulieu and the board of trustees would have disregarded it: a mystery burrow with shrewdly covered trapdoors at each end. An aide covered in an entry under the tent loosened the medication man, wriggled through the passage, retied the ropes, at that point ran to the house where the shaman had concluded they ought to be discovered (Christopher, 1973, p. 77). Alexander Phillip Maximillian, who went in the west in the mid 1800ââ¬â¢s, composed of some astonishing things achieved with common items by Hidatsa and Mandan shamans. ââ¬Å"The medication of one man comprises in making a snowball, which he rolls quite a while between his hands, so that finally it turns out to be hard and is changed into a white
Saturday, August 22, 2020
Retirement Plans essays
Retirement Plans papers In the present hyper-serious world, drawing in and holding the most ideal ability is critical to upper hand. One of the numerous ways associations achieve this is through the execution of retirement plans for their representatives. A retirement plan is a course of action to give individuals a salary, perhaps an annuity, during retirement when they are done acquiring a consistent pay from business, or an advantage from which an individual may draw a pay from varying (Retirement plans, 2007). This paper will outline the verifiable improvement of retirement plans and how they are right now being used today as a critical enlistment device. In the present hyper-serious world, pulling in and holding the most ideal ability is critical to upper hand. One of the numerous ways associations achieve this is through the usage of retirement plans for their workers. A retirement plan is a course of action to give individuals a pay, perhaps an annuity, during retirement when they are done gaining a consistent pay from business, or an advantage from which an individual may draw a pay from varying (Retirement plans, 2007). This paper will diagram the recorded improvement of retirement plans and how they are at present being used today as a critical enlistment device. Verifiable Overview of Retirement Plans: The American Express Company was the main association to offer a retirement plan, in the United States, with the primary private benefits plan, in 1875. Before this time, private - part designs didn't exist, as most associations were little, family-run ventures. By 1921, the training had gotten on, and the Revenue Act of 1921 was executed, absolving interest salary on benefit sharing plans or trusts for stock reward, from current tax collection. Assessments would be caused on trust salary as it was conveyed to representatives, when it surpassed th... <!
Statistics and Business Research Socio Economic Products
Question: Depict about the Statistics and Business Research for Socio Economic Products. Answer: Presentation This examination study has featured the effect of financial contrasts for the buying of items in the Australian market. According to the announcement of Pechey et al. (2013), financial contrasts inside an association emerge because of the misconception or miscommunication between the shoppers and the workers or between the bury representatives of the association. In this reason, the analyst has considered the financial contrasts as the autonomous variable and the buying of items is the needy variable (Dinsa et al. 2012). Then again, it tends to be referenced that various speculations and dependable models will be talked about in this investigation. These models and speculations will viably build the information on the investigation of the exploration. The models and the speculations will be gainful to assess the effect of the financial contrasts on the buying of items. Financial elements: According to the announcement of Chitnis et al. (2014), perspectives are the bothersome or the attractive estimation that mirror the conduct of the purchasers. In this association, it tends to be expressed that mentalities influence the aims. What's more, it tends to be expressed that perspectives mirror the aims, higher the attractive mentality, more prominent will be the goal, which is required to do. Howe et al. (2012) opined that demeanor is the key factor, which greaterly affects the purchasing choice. Then again, it tends to be referenced that the mentalities are associated with the individuals and the environmental factors. As per Blum (2013), it tends to be expressed that uplifting mentalities of the individuals will decidedly reflect to the encompassing individuals. What's more, effect of the financial contrasts on the buying of merchandise is likewise relying on the association between the abstract standards and the mentalities of the purchasers (Handbury, Rahkovsky and Schnell 2015). So as to make a business fruitful, financial contrast between the workers and the purchasers will alleviate. It will be diminished by the advancement of the trust and the compatibility with the shoppers. Thus, it tends to be referenced that more prominent correspondence expertise between the authoritative position and the customers can diminish the financial contrasts. In this reason, Galama and Van Kippersluis (2015) included that the customers are happy to buy the items from that association. The profitability of the organization will be successfully expanded. Financial incongruities can be forestalled when correspondence style and the conduct of the representatives is required to improve. Worldwide financial uniqueness: Figure : Global financial uniqueness (Source: Pickett and Wilkinson 2015) The above figure delineated the powerful factors, which mirrors the financial contrasts. By recognizing these elements, an association can moderate this dissimilarity. These elements can be talked about quickly in the accompanying: Higher creation rate and the less expensive work markets: As indicated by Blum (2013), modest work advertise features to expand the pace of creation. By and by, because of the tricky work, there is a more vulnerable buying power and the assembling merchandise and ventures will be hampered. The littler gatherings of the residential clients give these merchandise and the administrations. This specific financial situation will pull in the outside speculators. According to the announcement of Vijayanand (2012), because of the lower pace of the household works, the remote will be pulled in. Accordingly, it very well may be referenced that the financial uniqueness will increment. Higher utilization rate and the over market utilization: As per Howe et al. (2012), it very well may be expressed that a bigger extent of assembling products and the administrations in the less expensive work nations will be sent out to the unreasonable utilization countries. Thus, this will produce an endless loop, with which the global utilization will be focused inside a less markets. This buying conduct of wages inside the customer countries will keep on expanding. Then again, the buying intensity of the wages in the less expensive work countries will continually fall or stay unaltered. Lower pace of utilization and the under utilization markets: In the expressions of Handbury, Rahkovsky and Schnell (2015), under utilization is legitimately related with the monetary approaches, which intended to empower the less expensive work showcase. This circumstance may emerge because of the insufficient shopper request. Furthermore, it very well may be referenced that occasionally the laborers are paid lower compensation contrasted with the creation. Thus, their readiness towards the profitability will diminish. Thus, the profitability of the association will be perished. This will thusly mirror the utilization example of the purchasers. Worldwide financial uniqueness and the worldwide utilization difference: This area has attempted to feature that there is a dissimilarity in the salary level and the degree of utilization. Then again, Galama and Van Kippersluis (2015), included that the littler bit of the general populace would devour a bigger level of the universes assets. Subsequently, the more prominent level of the general populace is having a place under the base utilization level. Consequently, this examination study has shown the idea of over utilization and the under utilization so as to distinguish the effect of the financial contrasts. Because of the constrained assets in the worldwide market, the association won't have the option to create higher profitability. As indicated by the announcement of Pickett and Wilkinson (2015), it is required to decrease he financial hole between the workers and the shoppers. In this association, the representatives require to speak with the clients, so the workers will have the option to comprehend the prerequisite of them. With the assistance of the agreeable relationship, the exhibition of a business can be improved. The efficiency of the association will likewise be expanded. What's more, Blum (2013), opined that buyers would keep up a drawn out relationship with the association. Therefore, it very well may be surmised that the shopper dedication towards the organization will be kept up. In any case, misconstruing betwe en the customers and the representatives will reflect to doubt just as poor resolve. In this manner, it tends to be reasoned that financial hole isn't useful for an organization. Gantt graph utilizing the three achievements Writing Review is expected on Week 6. Information Collection and Analysis Report are expected on Week 10. Last Business Research (Capstone) Thesis is expected on week 14. Figure: Gantt Chart utilizing three achievements (Source: made by creator) Information assortment and examination strategy The point of the exploration is to discover an effect of financial contrasts on the customers decision of buying the items or devouring the administrations in an Australian Market. The analyst has picked Virgin Airlines to assess and discover the issues that the associations face due to the financial contrasts. Information assortment is a technique through which information is assortment whereupon a finding is based. The specialist has utilized distinct way to deal with examine the information. The exploration did not depend on contextual investigation yet the examination utilizes an elucidating approach. Two kinds of information assortment process are subjective and quantitative methodology (Creswell 2013). For this specific, investigate the scientist utilizes quantitative procedure for gathering the information. Quantitative information is gathered for the numerical examination of the perception. The analyst utilizes quantitative information assortment as the exploration is observa tional and enlightening in nature. Quantitative information is utilized to test the speculation that is gotten from the hypothesis. The information assortment system relies upon the examination questions. The quantitative information can be gathered utilizing different techniques, for example, tests, perceptions, meeting, polls and studies. Since the exploration is unmistakable in nature, the creator utilizes the techniques for polls and overviews to gather the information (Bryman 2015). The information is gathered by setting up a poll that is then overviewed on the web and through meeting process by the analyst. The poll is set up for the directors of Virgin Airlines, its workers and clients. The survey depends on the semi-organized example that depended on grouped examples. The survey contains both an open-finished inquiries and close finished inquiries. The nearby finished inquiries are for the representatives and directors of the association that is replied in expressive configuration. It contains five inquiries that are reviewed from workers and chiefs of the Virgin Airlines. The poll is reviewed utilizing meeting strategy and the specialist himself directs the meeting. The complete number of representatives that are studied records to 10. Open-finished inquiries are set up for the customers of Virgin aircrafts. The survey relies upon demography, for example, age, sex, religion and questions dependent on buyer decision and components influencing their purchasing conduct. The absolute quantities of purchasers that are reviewed are 50 (Weber 2015). The poll arranged is distributed on the web and study through web. It is done break down the financial issues and the effect of the financial contrasts on the buying choice of purchasers. The survey is set up to break down the mental perspective on the clients. It is done to break down the strategies utilized by the supervisors and representatives to settle the financial issues and issues. The request made was tried on an example of grouped examining from the business association and after that following an accommodation testing with the goal that any individual can answer the polls (Saaty and Vargas 2013). Thus, the scientist utilizes quantitative strategy to gather the da
Friday, August 21, 2020
Twisting and Convulsing by Bruja free essay sample
At the point when I previously tuned in to Bruja, an American darkened muck/stoner/fate metal trio, I was sitting in a dull room without anyone else. Not genuinely, truly I was perched on the love seat eating a pack of chips on a brilliant, clear evening. Intellectually, be that as it may, I was distant from everyone else in that dull room regardless of my genuine environmental factors which were the direct inverse of that. Brujas music simply has that power. Its brimming with sentiments of confinement, haziness, and, to a lesser degree, despair. Take those and put them to a specific squashing, lo-fi greatness, and youve got their latest demo, Twisting and Convulsing. The ancestral sounding drums that start off the demo give you a somewhat uncomfortable inclination, similar to strolling down a quiet street around evening time, realizing that somebody could in all likelihood be watching you and that you probably won't be protected. A silly inclination, perhaps, yet you simply cant help it. We will compose a custom paper test on Bending and Convulsing by Bruja or on the other hand any comparable subject explicitly for you Don't WasteYour Time Recruit WRITER Just 13.90/page When things truly start the coarse, low guitars that are placing scratches in the ground with their weight and the crude, puncturing, semi-coherent screeches of the psycho they have doing vocalsyou acknowledge how proud Bruja truly is. You feel like the beast that was under your bed as a child is snorting these burdensome, ghastliness like verses at you, and the ones that were in your storage room are his gathering. Theyll cause you to feel as miserable as they need, and youll love each second of it. Being a discharge in one of the more slow, sludgier ranges of metal as is this, the instrumentation is none also awe-inspiring. The drums trudge alongside their ceremonial like blasting and the guitars simply squash their way through every one of the 35 minutes of this demo, blending it up with a fascinating lead or two sometimes, as in Vivisection. Its the meaning of basic, yet viable. For whatever length of time that they keep the disposition up and the beat down, which they accomplish generally with just a couple of special cases (Another Vagabond ) then the music is generally open to leaving you alone completely inundated in it. At the point when they do somewhat get a move on they additionally get the overwhelming and drop the somber environment, so theres somewhat of a drop in quality in light of the fact that there is no bassist in this band, and the absence of low-end doesnt permit Bruja to depend entirely on largeness rather than a blend of substantial and all the down and o ut states of mind they make. Fortunately they dont leave you much space to criticize, on the grounds that Twisting and Convulsing comprises of what they excel at, and minimal more than that. While this demo is tedious, shows little variety among melodies, and doesnt give you much that truly latches onto your subconscious mind, Bruja comprehends what they can do and they can do it damn well. Theyre pounding, evil, and extraordinary; in the event that you figure they ought to do whatever else to satisfy you, they will joyfully keep on furrowing you down with their devastatingly thick, dull, discouraging, rambling fate conveyance. They dont care, yet I do and you ought to as well on the off chance that you need a section of ooze/fate/stoner or the entirety of the above to bite you up and let you out.
Monday, August 3, 2020
When Are Bad Credit Loans Dangerous
When Are Bad Credit Loans Dangerous When Are Bad Credit Loans Dangerous? When Are Bad Credit Loans Dangerous?Most people know that you need good credit to get a low interest rate on a personal loan. Fewer people know what to do when they need that personal loan but their credit is⦠letâs say, imperfect.If this describes you, then you may find yourself looking for a bad credit loan.Now, maybe youve heard that bad credit loans are dangerous. Thats because many of them are! Predatory lenders know that folks with bad or no credit are often desperate for money to cover unexpected expenses like car repairs and medical bills. If you have a financial emergency and no savings or credit to rely on, then youre more likely to let yourself get walked into a bad loan that will eventually trap you in a cycle of debt.But not every bad credit loan is the same. While some are predatory and dangerous, there are others that can get you through your financial emergency in a safe and financially responsible way. So how can you tell the difference? The next time you need a bad credit loan, be sure to ask your lenderIF THEY WANT YOU TO PAY AN ADVANCE FEEâ¦Lenders judge how likely a borrower is to repay a loan based on their credit rating. If a potential borrower has good credit, then theyre likely going to pay what they owe. If a potential borrower has bad credit, then theyll be considered a riskier prospect. A lender might be willing to look past a bad credit score if they can verify your income and ability to repay your loan at the end of the term. But if they want you to pay something in advance of the loan, something is definitely up.Brett Graff (@BrettGraff), writer at The Home Economist and author of Not Buying It: Stop Overspending and Start Raising Happier, Healthier, More Successful Kids explains the risk: âIf you have bad credit, you may be tempted by advance-fee loans. Here, the lenders tell you they guarantee the loans and they donât care about your credit history, but they are total scams. Real, legitimate lenders always care about c reditworthiness and scammers tell you what you want to hear, take your fee, and disappear.âAdvance-fee loans are, unfortunately, an increasingly common scam. The lender may be an online outfit that looks legitimate at a glance. They tell you your credit score isnt a problem, so long as you pay an application or processing fee upfront before they give you the loan. You pay the fee, and the lender disappears with your money.1IF THEY HAVE SHORT REPAYMENT TERMSâ¦.One reason why payday lenders are so dangerous is because they give you so little time to pay back your loan. Youâll be expected to repay the full principal, with interest and fees, in as little as two weeks.Canât pay it back? Well, youâll have the option to extend the loan for another couple weeks (for a costly fee). And this is where people get trapped. You can end up in the dreaded âcycle of debt,â forever extending your loan and never able to fully pay it back.Thereâs a reason payday lenders have gained a ba d reputation.Andrew Fiebart (@AndyFieb), co-owner of the Listen Money Matters (@MoneyMattersMan) podcast and blog, warns that âthe APR on payday loans is extremely high, so youâll pay more each time you extend your loan.âAPR (or annual percentage rate) includes fees and interest, so you can get a full picture of how much a loan will truly cost you. When you compare the average APR of a payday loan (nearly 400%2) with the APR of an average credit card (12%3), youll see just how outrageous these predatory fees really are.IF THEYâRE TRYING TO TAKE YOUR CARâ¦Fiebart singled out another dangerous bad credit loan you should steer clear of:âTitle loans require you to give your carâs title to the title loan company in exchange for an amount equal to the appraised value of your car. If you canât pay back the loan, you run the risk of the lender repossessing your car.âSince the APRs and payment terms of title lenders are similar to those of your bread and butter payday lender s, itâs terrifyingly easy to lose your car.No matter how sure you might be that you can pay it back, it isnât worth risking your car over.WHAT KIND OF CREDIT CHECK ARE THEY PERFORMING?Not all dangers are major and not all of them are exclusive to bad credit loans.Before applying for a loan, you should find out if the lender is going to perform a hard or a soft credit check.As mentioned above, you should expect a legitimate lender to perform a credit check. But a hard credit check can negatively affect your credit score.If you need a loan and you already have bad credit, try to find a lender who will perform a âsoft credit check, which wonât affect your credit score.We canât imagine anything less fair than being rejected from a loan you need AND having it further hurt your credit.IS THERE ANYTHING HIDDEN IN THE CONTRACT?At the end of the day, the reason why many bad credit loans become dangerous is because lenders arent upfront about the risks youâre being asked to take o n.All of the things weâve mentioned so far are risks that dangerous lenders will try to hide from you.We touched on some of the major concerns, but itâs important that you read through anything youâre signing very carefully, look at the loan in terms of its APR, and ask as many questions as you need.A good lender will want to work with you to make sure youâre getting the best loan possible.About the Contributors:Andrew Fiebert, is the Co-Founder and Chief Nerd at Listen Money Matters, a finance blog and podcast. After working as a data engineer at an investment bank, Andrew realized that there werenât any good places to learn about personal finance. Often left to his own devices to learn what was needed for finances, Andrew put together Listen Money Matters. Listen Money Matters is a community to help others get their financial situation straight.Brett Graff, has been seen writing and reporting on money and personal finance in The LA Times, Yahoo! Finance, Cosmopolitan, The New York Times and the Fiscal Policy Institute, to name a few. Brett also provides her insight in the column, The Home Economist, which is nationally syndicated and published in newspapers all over the country. Her book NOT BUYING IT: Raising Happier, Healthier More Successful Kids is now available!References: âAdvance-Fee Loan Scamsâ Michigan.gov. Accessed February 22, 2017 from http://www.michigan.gov/ag/0,4534,7-164-17337-252538,00.html âAverage Credit Card Interest Rates (APR) 2017â Valuepenguin.com. Accessed February 22, 2017 from https://www.valuepenguin.com/average-credit-card-interest-rates âWhat is a Payday Loan?â ConsumerFinance.gov. Accessed February 22, 2017 from https://www.consumerfinance.gov/askcfpb/1567/what-payday-loan.html
Monday, June 22, 2020
Happiness In My Life - Free Essay Example
Ive grown up my entire life being outdoors in some form or fashion. Being a kid in Texas, I had a lot of friends and family that were always out hunting or working on something that needed to be fixed on the property or lease. I feel like that has played a direct role in how I am as a person. My research is going to see if regularly participating in outdoor activities (huntsman, fisherman, and hiker exc.) allows you to have a happier life. Literature Review In my research so far I have found exactly what I thought I would find, and that is, the outdoors does have a positive effect on people. Dodson (1960) found that when kids go camping, they are taught to rely on themselves. No one is going to set up your tent in life. No one is going to give you your dinner in life. You have to go get it yourself. He also mentions the important idea that in camping you have to rely on others as well as yourself. Not everyone has the same job at a camping sight, some may need to collect firewo od, some may need to find water and so on and so forth. Everyone has their job to do and they have to do it the right way or everyone including yourself can be affected. Dodson also points out that in reality, only wealthy families get to go camping. For the children in the inner cities they have little or no opportunity to go camping. A possible study that could shed light on this would be starting a program that takes these kids out camping multiple times, then record if teachers, parents, or mentors see any type of change in behavior in the children. In Hinkleys et al. (2018) study we see that children who spend more time looking at a screen are subject to more health risks such as obesity, bone health, cardiovascular disease, and diminished social skills. In this cross sectional study of 575 participants of boys and girls 2-5 years old, boys spent on average 2 hours a day looking at a screen. Girls spent an average of 2.2 hours looking at a screen. Boys spent an average of 3.3 hours outside while girls spent 2.9 hours outside. Something interesting to point out is that the girl had higher rates for expressive behavior and compliant behavior. Is this because of too much time in one area? I think that it is a possibility, the boys are outside more than the girls and they get to make the rules as they play. This could make them more rebellious to rules and authority, whereas the girls are inside with mom or dad. A longitudinal study should be conducted to get more time lapsed results to see if the results carry over with time and possibly improve. The mothers of the children were given instructions to observe and to track their childs time both outside and while interacting with a screen. The study found that television, DVD, and video viewing are correlated with the childs social skills. The key to develop their social skills is that they had a balanced diet of screen viewing and outdoors play. (page 9) The outdoors and its affects doesnt just play a role in our young children it also can play a role with our elderly, which is often a group overlooked because theyre old or because theyve lived a long life already. Calkins, Szmerekovsky, and Biddle (2007) who studied people in nursing homes found some really uplifting results on dementia patients because of the effect of being outside. The subjects come from 3 different retirement homes in the Midwest and have dementia. The research showed that there was a small positive relationship between time spent outside and how well the participant spelt. Calkins et al. (2009) also points out that there are other small victories in the study like the participants grabbed at the workers less and they made less noises. There was only 17 participants in the study so right off the bat, if the researchers had a greater amount of participants the study might have had greater implications because the results do show a positive change but not by a lot. Also in the study they couldnt really forc e people to be outside or inside so the recorders have to have activities that incorporate being outside so that data could be collected. I feel that the study should have compared a retirement home in Hawaii or Florida vs Midwest. I would like to see a study done with dementia patients in a tropical place compared to one where residents dont get a lot of sun/outdoors time to see if the numbers are different, just to try and validate the study more. I found it interesting that in two of my sources, all of the data was collected by simply observing behavior. I do have some issues with this because, how can mothers, and people who work at retirement homes constantly watch their child or subject? There was probably some behaviors that were never seen or written down. Human error/laziness can come into play also, moms being too tired to write stuff down after a long day of work, so they essentially say screw it for the night. And we see retirement home workers mistreating the residen ce all the time on social media or on the news so there is a possibility of the workers also not wanting to take the time to properly record what is happening. The facility itself can be in question too, there is a possibility that the building itself might have an effect on the results. Acton (2016) is one that I think can have a powerful influence. Her study is all about the effects of a five day outdoor get away for young carer children. There are 8 young carer kids that volunteered to be a part of the study after hearing about it through a charity that supports young carer children. A young carer is a child that has to take care of a loved one, sibling, or parent because they physically cant take care of themselves. Growing up this way with so much responsibility can be damaging for a child because they never truly get to go out and play and be care free. They also are subject to more stress then adolescence at that age and it could leave lasting impressions on them. It was a quantitative (Emotional Literacy Checklists) and qualitative methods. They got their data from direct observation throughout the 5 days. They also had poems, interviews, and recorded discussion with the kids that were there on the trip. They spent their time in the woods making crafts, playing games, and teamwork activities. In the study the kids felt connected to nature. Could this be universal when kids are outside playing together? Is the connection with nature what keeps them outside and not locked in a trance by a screen? Maybe it makes them feel better much like the senior citizens with dementia (Calkins, 2009) The Thurston Family project is a study where schools that were connected to the TaMHS program were contacted about a chance to be a part of the study. Targeted Mental Health in Schools (TaMHS) is a mulit-agency program that trains teachers and other administration to better meet the needs of childrens mental health. Once they decided to be a part of the study they w ent to the outdoor center and that is where the study was crucial because subjects were about to feel like they were getting away from the hustle and bustle of everyday life. Another key aspect of the center was that everyone had a job to do. There were things that were expected of the residents like cleaning your bunk and your dorm room. Just by doing those few easy things parents reported that the relationship has started to strengthen because child/parent arguments were happening less and less. I would argue in my research that when youre in the outdoors theres a ton of jobs that have to be done and they all have to be done the right way because other people are counting on you much like in the Dodson study (1960). You can apply this to house hold chores because for a family to function properly (and to where moms and dads arent doing everything). There were 7 families involved and all of those were single parent households. I feel like that is a weakness in this study because it doesnt apply to family with mom and dad present at home. But five of the seven parents did decide to complete the full self-care course that propelled them to bettering their lives for example going back to school , becoming a class assistant, and becoming a nurse. All of the young children but one had improvements in satisfaction with school. Much like the Acton (2016), Flom, exal. (2011) set out to apply outdoor aspects to school counseling. And much like the Acton study, the children that were a part of this one also showed improvement in self-esteem, confidence and social skills. The counselors are trained in incorporating outdoor activities with the lesson plans by co-teaching with teachers by using the ASCAs National Model. One case of this working is when a teacher noticed a number of students who didnt have and extracurricular activities. So the teacher decided to start a fishing club and it was a huge success. Students that showed little interest and motivation in scho ol started to have improved behavior. And the number of students involved in the club keeps going up. This evidence shows the positive impact that the outdoors lifestyle can offer to troubled mines. I would like to see this incorporated more in college classrooms I think that it would help college students that have trouble with stress and anxiety. Tucker et al. (2016) brings OBH (Outdoor Behavioral Healthcare) into play. In my other sources there hasnt been anything that mentions OBH but it is what Acton (2016) and McManus (2012) are doing with their subjects. OBH was developed as a form of therapy to inspire resilience, self-reliance, and teamwork to project change upon those involved. Most of the article gives you history over OBH but there is a case study that is done over a boy named Andrew. Andrew was a troubled child, he would drink and smoke marijuana, hed get suspended from school and would defy his parents authority. Because of his moderate substance abuse, his parents sent him off to an OBH program and even after only 3 weeks of doing activates like rock climbing, canoeing, hiking, mountain biking and building fires without matches, his defiance began to diminish and he began to buy in the program. He had found his natural high through the outdoors (page 38). Andrew had made dramatic changes and his therapist helped him create a plan for when he goes back home so that he doesnt fall back into that downward cycle that he was in before. And through this program he found a passion for mountain biking and took that back home with him to cope with the old triggers that would previously send him back to abusing substances. The downfall of OBH is that kids do make these great strides while in the wilderness but then go back to their old ways once at home. Tucker suggests that the family needs to be integrated into the therapy instead of children being sent away by themselves because there can be underlining problems in the family dynamic that can tri gger negative behavior. Research shows that families that are in a camp like setting, working together and doing activities, are brought together and form bonds that werent there previously (Haber 2011, page 40) Outdoor activities are also used to help people cope with extreme tragedy. In 2009 Typhoon Morakot touched down and was the strongest typhoon ever recorded in Taiwan. It claimed 704 souls and had another 18 missing and countless damage to almost 170,000 homes in Taiwan. In Chaos (2015) study they had 292 displaced refugees that were 65 years or older. In the studys they wanted to see if the typhoon had made any of the refugees go into depression or have signs of depression based on a 10 point shortened version of the Center of Epidemiologic Studies Depression Scale or CES-D. And they were also asked how often they had been outside doing activities from a scale of 1-3. 1 = not at all, 2 = sometimes (less than once a week) and 3 = often (once a week or more). They were also asked how they felt about their communities and how safe they felt it was and how friendly the people were. The findings of this study are something to be happy about. There was a positive correlation between the amount of outdoor activities and community cohesion, meaning the more the people were outside doing activities the better outlook they had on their community an neighbors around them. And there was a negative correlation between community cohesion and depression, the higher the cohesion level the lower level of depression in the refugee (page 943). An important thing to take into consideration is that this study was conducted 4 years after the typhoon so you really get to see the long term effect of the three variables that were being studied. Combs et al. (2015) did a very interesting study that I hadnt come across really. I have one other source that has parental input (Hinkley et al. 2018) but not completely from the parent perspective after treatment. The study is a quasi-experimental design with no control group and it had 659 parents of children that were a part of one of 4 OBH facilities/programs. There was 792 total kids in one of these three programs but only 83% (659) completed the program. Of the 659 only 200 parents were selected to complete the 18 month follow up. If all parents were to complete the 18 month follow up there could be higher rates of satisfaction. Data was collected from the parents electronically by email. Parents did pre-treatment assessments of their kids and reported high levels of emotional and behavioral dysfunction (page 358) but the post treatment analysis showed dramatic improvements from the children involved with most scoring out with a normal range of functioning which means they were able to act appropriately like the everyday person. Some of the kids did go back home and showed a little back tracking but nothing that was statistically significant (page 358). The clients that scored very high on pre- treatment test done by their parents showed the most dramatic improvements when it came to substance abuse, anxiety, behavioral, and attachment disorder, length of stay, age at intake, parents marital status, and adoption status. Im immediately taken back to the OBH therapy mixed with family therapy in Tucker et al. (2016) the completion rate might have been higher than 83% if the families of the children were there to go through family exercises. Another factor could be that only 65% of the childrens families had both the mother and father at home. I cant help but suspect that if the parents were together that one, the child may not even be there in the first place, and two would the overall completion rate be higher? Roberts et al. (2017) had a convenience sample of 186 kids that were enrolled into a wilderness therapy program. A hierarchical linear model was used to analyze the data given back. (page 45). After completing the program the clients were given the Outcome Question naire-45.2 or OQ-45.2. The OQ-45.2 is used to measure important functioning symptoms like: interpersonal problems social role functioning and quality of life. They had the clients take the test before, during, and after they had completed the program. In Figure 1 one (page 49) over a five week period we see a steady decline in all scores from the total score to symptom distress, social role performance, and interpersonal relationships, showing progress for the clients involved. The problem with the study is that over the 18 month period they would receive less and less responses. Starting out with a response rate of 82.3% in week one, to 42.5% response rate at the end of the 18 month period. Even though success was found there was still a lot of data that wasnt collected just because people werent reporting it back to the researchers. One can think that maybe they clients went back home and got back into the lifestyle they previously were in. Or maybe life just got in the way for so me of them but Ill go back and mention the family being incorporated to the therapy as a possibility to getting better responses and greater results thoughts the program itself before the clients leave. As we can see from the resources that I have found that there is a relationship between being outside and health/behavior whether it be medical or social applications, they can be pursued and presented to the public for the betterment of all people. The simplicity of being outside in nature soaking up the sun was our first prescription at the dawn of time. Its time we get back to our roots and dig our toes back into the dirt.
Saturday, May 23, 2020
The Adventures Of Huck Finn By William Twain - 865 Words
Huck Finn encounters many obstacles, either physical or mental, unintentional or intentional, that test his ability to overcome them by means of ââ¬Å"doing wrongâ⬠or ââ¬Å"doing rightâ⬠. The concept of ââ¬Å"rightâ⬠can be perceived throughout the novel as the ability to follow religion, (Christianity in this case), to be enrolled in school, and to follow a set of morals that come with that particular time frame (1840s). ââ¬Å"When you got to the table you couldn t go right to eating, but you had to wait for the widow to tuck down her head and grumble a little over the victualsâ⬠¦Ã¢â¬ (ch.1 pg.2) ââ¬Å"After supper she got out her book and learned me about Moses and the Bulrushers, and i was in a sweat to find out all about him;â⬠. (ch.1 pg.2). These statements show how the current caretaker, the ââ¬Å"widowâ⬠, is making sure that religion is a big part of Huck s education and moral compass. She even goes on to describe heaven (the good place) and hell (the bad place). ââ¬Å" Then she told me all about the bad place, and i said i wished i was thereâ⬠. (ch.1 pg.2) ââ¬Å"Now she had got a start, and she went on and told me all about the good placeâ⬠. (ch.1 pg.3). ââ¬Å"Doing wrongâ⬠, as described in the story, can be seen as: smoking, showing characteristics of being ââ¬Å"lazyâ⬠, stealing, and one of the more serious acts, helping or developing a relationship that isn t work related with a ââ¬Å"slaveâ⬠. ââ¬Å"Pretty soon i wanted to smoke, and asked the widow to let me. But she wouldn t. She said it was a mean practice and wasn t clean,Show MoreRelatedThe Adventures Of Huckleberry Finn And Its Characterization951 Words à |à 4 PagesBouchey Eng. 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Monday, May 18, 2020
Different welding techniques - Free Essay Example
Sample details Pages: 21 Words: 6389 Downloads: 8 Date added: 2017/06/26 Category Statistics Essay Did you like this example? CHAPTER 1: INTRODUCTION 1.1 INTRODUCTION OF THE FSW TECHNIQUE In todays modern world there are many different welding techniques to join metals. They range from the conventional oxyacetylene torch welding to laser welding. The two general categories in which all the types of welding can be divided is fusion welding and solid state welding. The fusion welding process involves chemical bonding of the metal in the molten stage and may need a filler material such as a consumable electrode or a spool of wire of the filler material, the process may also need a inert ambience in order to avoid oxidation of the molten metal, this could be achieved by a flux material or a inert gas shield in the weld zone, there could be need for adequate surface preparations, examples of fusion welding are metal inert gas welding (MIG), tungsten inert gas welding (TIG) and laser welding. There are many disadvantages in the welding techniques where the metal is heated to its melting temperatures and let it solidify to form the joint. The melting and solidification causes the mechanical properties of the weld to deteriorate such as low tensile strength, fatigue strength and ductility. The disadvantages also include porosity, oxidation, microsegregation, hot cracking and other microstructural defects in the joint. The process also limits the comb ination of the metals that can be joined because of the different thermal coefficients of conductivity and expansion of different metals. Donââ¬â¢t waste time! Our writers will create an original "Different welding techniques" essay for you Create order The solid state welding is the process where coalescence is produced at temperatures below the melting temperatures of the base metal with out any need for the filler material or any inert ambience because the metal does not reach its melting temperature for the oxidation to occur, examples of solid state welding are friction welding, explosion welding, forge welding, hot pressure welding and ultrasonic welding. The three important parameters time, temperature and pressure individually or in combinations produce the joint in the base metal. As the metal in solid state welding does not reach its melting temperatures so there are fewer defects caused due to the melting and solidification of the metal. In solid state welding the metals being joined retain their original properties as melting does not occur in the joint and the heat affected zone (HAZ) is also very small compared to fusion welding techniques where most of the deterioration of the strengths and ductility begins. Dissimila r metals can be joined with ease as the thermal expansion coefficients and the thermal conductivity coefficients are less important as compared to fusion welding. Friction stir welding (FSW) is an upgraded version of friction welding. The conventional friction welding is done by moving the parts to be joined relative to each other along a common interface also applying compressive forces across the joint. The frictional heat generated at the interface due to rubbing softens the metal and the soft metal gets extruded due to the compressive forces and the joint forms in the clear material, the relative motion is stopped and compressive forces are increased to form a sound weld before the weld is allowed to cool. Friction stir welding is also a solid state welding processes; this remarkable upgradation of friction welding was invented in 1991 in The Welding Institute (TWI) [4]. The process starts with clamping the plates to be welded to a backing plate so that the plates do not fly away during the welding process. A rotating wear resistant tool is plunged on the interface between the plates to a predetermined depth and moves forward in the interface between the plates to form the weld. The advantages of FSW technique is that it is environment friendly, energy efficient, there is no necessity for gas shielding for welding Al, mechanical properties as proven by fatigue, tensile tests are excellent, there is no fume, no porosity, no spatter and low shrinkage of the metal due to welding in the solid state of the metal and an excellent way of joining dissimilar and previously unweldable metals. 1.2 ALUMINUM ALLOYS AND WELDING OF ALUMINUM ALLOYS Aluminum is the most abundant metal available in the earths crust, steel was the most used metal in 19th century but Aluminium has become a strong competitor for steel in engineering applications. Aluminium has many attractive properties compared to steel it is economical and versatile to use that is the reason it is used a lot in the aerospace, automobile and other industries. The most attractive properties of aluminum and its alloys which make them suitable for a wide variety of applications are their light weight, appearance, frabricability, strength and corrosion resistance. The most important property of aluminum is its ability to change its properties in a very versatile manner; it is amazing how much the properties can change from the pure aluminum metal to its most complicate alloys. There are more then a couple of hundreds alloys of aluminum alloys and many are being modified form them internationally. Aluminium alloys have very low density compared to steel it has almost on e thirds the density of steel. Properly treated alloys of aluminum can resist the oxidation process which steel can not resist; it can also resist corrosion by water, salt and other factors. There are many different methods available for joining aluminum and its alloys. The selection of the method depends on many factors such as geometry and the material of the parts to be joined, required strength of the joint, permanent or dismountable joint, number of parts to be joined, the aesthetic appeal of the joint and the service conditions such as moisture, temperature, inert atmosphere and corrosion. Welding is one of the most used methods for aluminum. Most alloys of aluminum are easily weldable. MIG and TIG are the welding processes which are used the most, but there are some problems associated with this welding process like porosity, lack of fusion due to oxide layers, incomplete penetration, cracks, inclusions and undercut, but they can be joined by other methods such as resistance welding, friction welding, stud welding and laser welding. When welding many physical and chemical changes occur such as oxide formation, dissolution of hydrogen in molten aluminum and lack of color change when heated. The formation of oxides of aluminum is because of its strong affinity to oxygen, aluminum oxidizes very quickly after it has been exposed to oxygen. Aluminum oxide forms if the metal is joined using fusion welding processes, and aluminum oxide has a high melting point temperature than the metal and its alloys it self so it results in incomplete fusion if present when joined by fusion welding processes. Aluminum oxide is a electrical insulator if it is thick enough it is capable of preventing the arc which starts the welding process, so special methods such as inert gas welding, or use of fluxes is necessary if aluminum has to be welded using the fusion welding processes. Hydrogen has high solubility in liquid aluminum when the weld pool is at high temperature and the metal is still in liquid state the metal absorbs lots of hydrogen which has very low solubility in the solid state of the metal. The trapped hydrogen can not escape and forms porosity in the weld. All the sources of hydrogen has to be eliminated in order to get sound welds such as lubricants on base metal or the filler material, moisture on the surface of base metal or condensations inside the welding equipment if it uses water cooling and moisture in the shielding inert gases. These precautions require considerable pretreatment of the workpiece to be welded and the welding equipment. Hot cracking is also a problem of major concern when welding aluminum, it occurs due to the high thermal expansion of aluminum, large change in the volume of the metal upon melting and solidification and its wide range of solidification temperatures. The heat treatable alloys have greater amounts of alloying elements so the weld crack sensitivity is of concern. The thermal expansion of aluminum is twice that of steel, in fusion welding process the melting and cooling occurs very fast which is the reason for residual stress concentrations. Weldability of some aluminum alloys is an issue with the fusion welding processes. The 2000 series, 5000 series, 6000 series and 7000 series of aluminum alloys have different weldabilities. The 2000 series of aluminum alloys have poor weldability generally because of the cooper content which causes hot cracking and poor solidification microstructure and porosity in the fusion zone so the fusion welding processes are not very suitable for these alloys. The 5000 series of aluminum alloys with more than 3% of Mg content is susceptible to cracking due to stress concentration in corrosive environments, so high Mg alloys of 5000 series of aluminum should not be exposed to corrosive environments at high temperatures to avoid stress corrosion cracking. All the 6000 series of aluminum are readily weldable but are some times susceptible to hot cracking under certain conditions. The 7000 series of aluminum are both weldable and non-weldable depending on the chemical composition of the alloy. Alloys with low Zn-Mg and Cu content are readily weldable and they have the special ability of recovering the strength lost in the HAZ after some weeks of storage after the weld. Alloys with high Zn-Mg and Cu content have a high tendency to hot crack after welding. All the 7000 series of aluminum have the sensitivity to stress concentration cracking. All these problems associated with the welding of these different alloys of aluminum has lead to the development of solid state welding processes like Friction Stir Welding technique which is an upgraded version of the friction welding processes. This process has many advantages associated with it, and it can weld many aluminum alloys such as 2000 and 7000 series which are difficult to weld by fusion welding processes. The advantages of the Friction Stir Welding processes are low distortion even in long welds, no fuse, no porosity, no spatter, low shrinkage, can operate in all positions, very energy efficient and excellent mechanical properties as proven by the fatigue, tension and bend tests. 1.3 Conventional Welding Processes of Aluminum A brief description of the most common processes, their applications on aluminum and limitations are given below. 1.3.1 Gas Tungsten Arc Welding (GTAW): In gas tungsten arc welding process the heat generated by an arc, which is maintained between the workpiece and a non-consumable tungsten, electrode is used to fuse the joint area. The arc is sustained in an inert gas, which serves to protect the weld pool and the electrode from atmospheric contamination as shown in Figure 2.3. The process has the following features: It is conducted in a chemically inert atmosphere; The arc energy density is relatively high; The process is very controllable; Joint quality is usually high; Deposition rates and joint completion rates are low. The process may be applied to the joining of a wide range of engineering materials including stainless steel, aluminum alloys and reactive metals such as titanium. These features of the process lead to its widespread application in aerospace, nuclear reprocessing and power generation industries as well as in the fabrication of chemical process plant, food processing and brewing equipment. 1.3.2 Shielded metal arc welding (SMAW): Shielded metal arc welding has for many years been one of the most common techniques applied to the fabrication of steels. The process uses an arc as the heat source but shielding is provided by gases generated by the decomposition of the electrode coating material and by the slag produced by the melting of mineral constituents of the coating. In addition to heating and melting the parent material the arc also melts the core of the electrode and thereby provides filler material for the joint. The electrode coating may also be used as source of alloying elements and additional filler material. The flux and electrode chemistry may be formulated to deposit wear- and corrosion-resistant layers for surface protection as shown in Figure 2.4. Significant features of the process are: Equipment requirement are simple; A large range of consumables are available; The process is extremely portable; The operating efficiency is low; It is labor intensive. For these reasons the process has been traditionally used in structural steel fabrication, shipbuilding and heavy engineering as well as for small batch production and maintenance. 1.3.3 Plasma welding: Plasma welding uses the heat generated by a constricted arc to fuse the joint area; the arc is formed between the tip of a non-consumable electrode and either the work piece or the constricting nozzle as shown in Figure 2.5. A wide range of shielding and cutting gases is used depending on the mode of operation and the application. In the normal transferred arc mode the arc is maintained between the electrode and the work piece; the electrode is usually the cathode and the work piece is connected to the positive side of the power supply. In this mode a high energy density is achieved and the process may be used effectively for welding and cutting. The features of the process depend on the operating mode and the current, but in summary the plasma process has the following characteristics: Good low-current arc stability Improved directionality compared with GTAW Improved melting efficiency compared with GTAW Possibility of keyhole welding The keyhole technique is the high heat concentration can penetrate completely through the joint. These features of the process make it suitable for a range of applications including the joining of very thin materials, the encapsulation of electronic components and sensors, and high- speed longitudinal welds on strip and pipe. 1.3.4 Laser welding The laser may be used as an alternative heat source for fusion welding. The focused power density of the laser can reach 1010 or 1012 Wm-2 and welding is often carried out using the keyhole technique. Significant features of laser welding are: Very confined heat source at low power Deep penetration at high power Reduced distortion and thermal damage Out-of-vacuum technique High equipment cost These features have led to the application of leaders for micro joining of electronic components, but the process is also being applied to the fabrication of automotive components and precision machine tool parts in heavy section steel. 1.4 Weld Defects using Conventional Processes Because of a history of thermal cycling and attendant micro structural changes, a welded joint may develop certain discontinuities. Welding discontinuities can also be caused by inadequate or careless application of established welding technologies or substandard operator training. The major discontinuities that affect weld quality are described below. 1.4.1 Porosity: Trapped gases released during melting of the weld area and trapped during solidification, chemical reactions during welding, or contaminants, cause porosity in welds. Most welded joints contain some porosity, which is generally spherical in shape or in the form of elongated pockets. The distribution of porosity in the weld zone may be random, or it may be concentrated in a certain region. Porosity in welds can be reduced by the following methods: Proper selection of electrodes and filler metals. Improving welding techniques, such as preheating the weld area or increasing the rate of heat input. Proper cleaning and preventing contaminants from entering the weld zone. Slowing the welding speed to allow time for gas to escape.8 1.4.2 Slag inclusions: Slag inclusions are compounds such as oxides, fluxes, and electrode-coating materials that are trapped in the weld zone. If shielding gases are not effective during welding, contamination from the environment may also contribute to such inclusions. Welding conditions are important, and with proper techniques the molten slag will float to the surface of the molten weld metal and not be entrapped. Slag inclusions may be prevented by: Cleaning the weld-bead surface before the next layer is deposited by using a hand or power wire brush. Providing adequate shielding gas. Redesigning the joint to permit sufficient space for proper manipulation of the puddle of molten weld metal. 1.4.3. Incomplete fusion and penetration: A better weld can be obtained by: Raising the temperature of the base metal. Cleaning the weld area prior to welding. Changing the joint design and type of electrode. Providing adequate shielding gas. Incomplete occurs when the depth of the welded joint is insufficient. Penetration can be improved by: Increasing the heat input. Lowering travel speed during welding. Changing the joint design. Ensuring that surfaces to be joined fit properly.8 1.4.4 Weld profile: Weld profile is important not only because of its effects on the strength and appearance of the weld, but also because it can indicate incomplete fusion or the presence of slag inclusions in multiple-layer welds. Under filling results when the joint is not filled with the proper amount of weld metal Figure 2.7. Undercutting results from melting away the base metal and subsequently generating a groove in the shape of recess or notch. Unless it is not deep or sharp, an undercut can act as a stress raiser and reduce the fatigue strength of the joint and may lead to premature failure. Overlap is a surface discontinuity generally caused by poor welding practice and selection of the wrong materials. A proper weld is shown in Figure 2.7c.5 1.4.5 Cracks: Cracks may occur in various locations and direction in the weld area. The types of cracks are typically longitudinal, transverse, crater, and toe cracks Figure 2.8. These cracks generally result from a combination of the following factors: Temperature gradients that cause thermal stresses in the weld zone. Variations in the composition of the weld zone that cause different contractions. Embitterment of grain boundaries by segregation of elements, such as sulfur, to the grain boundaries as the solid-liquid boundary moves when the weld metal begins to solidify. Hydrogen embitterment. Inability of the weld metal to contract during cooling is a situation similar to hot tears that develops in castings and related to excessive restraint of the work piece. (a) crater cracks. (b)Various types of cracks in butt and T joints.8 Cracks are classified as hot or cold cracks. Hot cracks occur while the joint is still at elevated temperatures. Cold cracks develop after the weld metal has solidified. Some crack prevention measures are: Change the joint design to minimize stresses from shrinkage during cooling. Change welding-process parameters, procedures, and sequence. Preheat components being welded. Avoid rapid cooling of the components after welding.8 1.4.6 Lameller tears: In describing the anisotropy of plastically deformed metals, we stated that because of the alignment of nonmetallic impurities and inclusions (stringers), the work piece is weaker when tested in its thickness direction. This condition is particularly evident in rolled plates and structural shapes. In welding such components, lamellar tears may develop because of shrinkage of the members in the members or by changing the joint design to make the weld bead penetrate the wearer member more deeply.8 1.4.7 Surface damage: During welding, some of the metal may spatter and be deposited as small droplets on adjacent surfaces. In arc welding possess, the electrode may inadvertently contact the parts being welded at places not in the weld zone (arc strikes). Such surface discontinuities may be objectionable for reasons of appearance or subsequent use of the welded part. If severe, these discontinuities may adversely affect the properties of the welded structure, particularly for notch-sensitive metals. Using proper welding techniques and procedures is important in avoiding surface damage.8 1.5 Skill and Training requirements: Many of the traditional welding processes required high levels of operator skill and dexterity, this can involve costly training programs, particularly when the procedural requirement described above need to be met. The newer processes can offer some reduction in the overall skill requirement but this unfortunately been replaced in some cases by more complex equipment and the time involved in establishing the process parameters has brought about a reduction in operating factor. Developments, which seek to simplify the operation of the equipment, will be described below but effective use of even the most advanced processes and equipment requires appropriate levels of operator and support staff training. The cost of this training will usually be recovered very quickly in improved productivity and quality. 1.6 Areas for development: Advances in welding processes may be justified in: Increased deposition rate; Reduced cycle time; Improved process control; Reduced repair rate; Reduced weld size; Reduced joint preparation time; Improved operating factor; Reduction in post-weld operations; Reduction in potential safety hazards; Removal of the operator from hazardous area; Simplified equipment setting. Some or all these requirement have been met in many of the process developments which have occurred in the ten years; these will be described in detail in the following chapters but the current trends in the of this technology are examined below. 1.7 New processes: The Primary incentive for welding process development is the need to improve the total cost effectiveness of joining operations in requirement for new processes. Recently, concern over the safety of the welding environment and the potential shortage of skilled technicians and operator in many countries have become important considerations. Many of the traditional welding techniques described in this Chapter are regarded as costly and hazardous and it is possible to improve both of these aspects significantly by employing some of the advanced process developments described in the following chapters. The use of new joining techniques such as Friction Stir Welding appears to be increasing since it does not involve melting. The application of these processes has in the past been restricted, but with the increased recognition of the benefits of automation and the requirement for high-integrity joints in newer materials it is envisaged that the use of these techniques will grow. This is a new process originally intended for welding of aerospace alloys, especially aluminum extrusions. Whereas in conventional friction welding, heating of interfaces is achieved through friction by rubbing two surfaces, in the FSW process, a third body is rubbed against the two surfaces to be joined in the form of a small rotating non-consumable tool that is plunged into the joint. The contact pressure causes frictional heating. The probe at the tip of the rotating tool forces heating and mixing or stirring of the material in the joint. 1.8 Research objectives: The objectives of our project are to: Adopt FSW to a milling machine Design the FSW tools, select its material and have it manufactured Design the required clamping system Apply FSW to plates of an alloy that is not readily weldable by conventional methods Investigate FSW parameters (RPM, Feed Rate and Axial force) Analyze conventionally welded and Friction Stir welded sections then compare their properties. The objective of this research is to characterize the mechanical properties of friction stir welded joints and study the micro structure of the base metal and the weld nugget evolved during the friction stir welding of similar and dissimilar alloys of Aluminum. Aluminum 2024 and 7075 are considered for this investigation. The mechanical properties such as ultimate tensile strength, yield strength, formability, ductility and vickers hardness are measured and an effort is made to find out a relation between the process variables and properties of the weld. The optimal process parameters for the Friction-Stir welding of AA2024 and AA7075 will be defined based on the experimental results. Having understood the significance of FSP, the main objective of this thesis is to investigate the effect of process parameters like rotational and translational speeds on the forces generated during FSP of aluminum alloys and relate these forces with the microstructure evolved in order to optimize the process. The specific objectives of the work presented are: Design and conduct FS processing experiments on aluminum alloy for different combinations of rotational and translation speeds. Measuring the generated processing forces during FSP of aluminum alloys Examine the microstructural of the processed sheets using transmission electron microscope (TEM). Attempt to establish a correlation between these measured forces and the resulting microstructure. Chapter 2 Review of Literature 2.1 General Idea of the Friction Stir Technology This section gives an insight into the innovative technology called friction stir technology. The action of rubbing two objects together causing friction to provide heat is one dating back many centuries as stated by Thomas et.al [1]. The principles of this method now form the basis of many traditional and novel friction welding, surfacing and processing techniques. The friction process is an efficient and controllable method of plasticizing a specific area on a material, and thus removing contaminants in preparation for welding, surfacing/cladding or extrusion. The process is environmentally friendly as it does not require consumables (filler wire, flux or gas) and produces no fumes. In friction welding, heat is produced by rubbing components together under load. Once the required temperature and material deformation is reached, the action is terminated and the load is maintained or increased to create a solid phase bond. Friction is ideal for welding dissimilar metals with very different melting temperatures and physical properties. Some of the friction stir technologies ar e shown in the Fig.2-1. Work carried out at TWI by Thomas et.al [2,3] has demonstrated that several alternative techniques exist or are being developed to meet the requirement for consistent and reliable joining of mass production aluminum alloy vehicle bodies. Three of these techniques (mechanical fasteners, lasers and friction stir welding) are likely to make an impact in industrial processing over the next 5 years. FSW could be applied in the manufacture of straight-line welds in sheet and extrusions as a low cost alternative to arc welding (e.g. in the fabrication of truck floors or walls). The development of robotized friction stir welding heads could extend the range of applications into three dimensional components. Mishra et.al [4] extended the FSW innovation to process Al 7075 and Al 5083 in order to render them superplastic. They observed that the grains obtained were recrystallized, equiaxed and homogeneous with average grain sizes 300 rpm no abnormal grain size was observed. Friction stir processing of nanophase aluminum alloys led to high strength ~ 650 MPa with good ductility above 10% [Figure 2-4]. Improvements in ductility were due to a significantly improved homogenization of the microstructure during FSP. The FSP technique is very effective in producing ductile, very high specific strength aluminum alloys, such as the Al-Ti-Cu and Al-Ti-Ni as investigated by Beron et al. [26]. The authors investigated two processes: hot isostatic pressing (HIP) and friction stir process (FSP) and compared the microstructures and corresponding properties resulted from the respective processes on 7075 Al alloy. HIP results in a very high strength alloy with low ductility and inhomogeneous structure. But FSP results in comparatively low strength below 740Mpa but very high ductility at temperatures above 300Ãâà °C at ~500Ãâà °C. However the FS processing parameters can be optimized to lower both the operating temperature and time at the temperature in order to improve the strength further. Thus this paper concludes that FSP produces high strength Al alloys with significant ductility. Sato et al. [27] investigated the effect of rotational speed on the microstructure and hardness during friction stir welding of Al 6063-T5. They concluded that the maximum temperature of the welding thermal cycle increased with increase in rotational speed. And also it is observed that the recrystallized grain size increased exponentially with the increasing maximum temperature. Thus they clearly indicated that there is an increase in grain size as the rotational speed increased. Sato et al. investigated the precipitation sequence in friction stir weld of 6063 Al alloy during aging [28] and concluded that post weld annealing at 440K for 12hrs gives greater hardness in overall weld than in the as- received base material and also shifted the minimum hardness from as-welded minimum hardness region to the precipitated-coarsened region. They have also studied the micro-texture of the friction stir welded 6063-T5 Al alloy using orientation imaging microscopy [29]. Sato et al. [30] examined the dominant microstructural factors governing the global tensile properties of a FS welded joint of 6063 Al alloy by estimating the distribution of local tensile properties corresponding to local microstructure and hardness. They concluded that the minimum hardness determined global yield and ultimate tensile strengths of the weld joint. They stated that in a homogeneously hard joint, such as a solution heat treated and aged weld, a fracture was observed to be located in a region with a minimum average Taylor factor (M) which is equivalent to s/tc where s is the applied uniaxial stress and tc the shear stress working on active plane systems. Lockwood et al. [31] studied the global and local mechanical response of FS welded AA2024 both experimentally and numerically. Transverse loaded tensile specimens via the digital image correlation technique obtained full field strain measurements. Assuming an iso-stress configuration, local constitutive data were determined for the various weld regions and were used as input for a 2D finite element model. The numerical results compared well with the experimental results in predicting the global mechanical response especially the strain levels. It was also observed that the global strain level was approximately 4% for both the model and experiment. Mahoney et al. [32] conducted longitudinal and transverse (to the friction stir welded) tensile testing on AA 7075 alloy, which demonstrated that the weakest region associated with FSW was the low temperature location within the heat-affected zone about 7 to 8 mm from the edge of the weld nugget. The yield strength at this location was 45pct less than that of the base metal while; the ultimate tensile strength was 25pct less. Thus concluded that in weldable Al alloys typically, the weld zone would exhibits a 30 to 60 pct reduction in yield and ultimate strengths, hence the losses due to friction stir process were at the lower end of the range for Al alloys. Mitchell et al. [33] performed FSW of Ãâà ¼ thick AA6061 sheets for eight combinations of rotational and translational speeds. In their work they presented the forces generated especially the transverse and translation forces and also the temperatures. The temperature is measured using thermocouples. They observed that the transverse force was greater than translation force for all the combinations of speeds and feeds. Their work clearly showed that there exists a unique combination of shear and normal forces that produces a friction stir weld and have stated that the understanding of the contribution of two forces and the relationship to each other was important in modeling the FSW process. Jata et al. [34] FS welded Al 7050-T7451 alloy to investigate the effects on the microstructure and mechanical properties. Results were discussed for the as-welded condition (as-FSW) and for a postweld heat-treated condition consisting of 121Ãâà °C for 24 hours (as-FSW + T6) did not result in an improvement either in the strength or the ductility of the welded material. It was evident from TEM analysis that the FS welding process transformed the initial 1mm sized pancake-shaped grains in the parent material to fine 1to5Ãâà µm dynamically recrystallized grains. Tensile specimens tested transverse to the weld showed that there was a 25 to 30 pct reduction in the strength level, a 60 pct reduction in the elongation in the as-FSW condition, and that the fracture path was observed in the HAZ. Comparison of fatigue-crack growth rates (FCGRs) between the parent T7451 material and the as-FSW + T6 condition, at a stress ratio of R = 0.33, showed that the FCG resistance of the weld-nug get region decreased, while that of the HAZ increased. 2.3 Studies on Tool and Tool Wear during FSW The tool design plays a very crucial role in friction stir technology. Hence it becomes an important area of study to make the process more efficient. There have been few contributions in this area which can be jotted as follows. The design of the tool is the key to the successful application of the process to a greater range of materials and over a wider range of thickness. A number of different high performance tool designs have been investigated. The investigations by Thomas et al. [35] describe the recent developments using these enhanced tools from the perspective of existing and potential applications. Aluminum alloy plates of thickness 1mm to 50mm have been successfully friction stir welded in one pass and a 75mm thick FSW weld in 6082 T6 aluminum alloy plate. Encouraging results and good performance have been achieved by using the MX TrifluteTM type tools to make single pass welds in a number of materials, from 6mm to 50mm in thickness. Typically, the WhorlTM reduced the displaced volume by about 60%, while the MX TrifluteTM reduced the displaced volume by about 70%. Tool wear in a right-hand-threaded, carbon steel nib reached a maximum at 1000 rpm counter-clockwise rotation speed in the FSW of an aluminum 6061+20 vol. % Al2O3 MMC where the corresponding, effective wear rate was approximately 0.64%/cm as studied by Prado et al. [36]. Above 1000 rpm the wear rate declined. It was approximately 0.42% /cm at 1500 rpm and 0.56%/cm at 2000 rpm. There was no measurable wear and essentially zero wear rate for the same nib rotating at 1000rpm for the FSW of a commercially Al6061 alloy. 2.4 Microstructural studies on friction stirred alloys A basic understanding of the evolution of microstructure in the dynamically recrystallized region of FS material and relation of this with the deformation process variables of strain, strain rate, temperature and process parameters is very essential. This section would give an insight into such studies. Peel et.al. [7] reported the results of microstructural, mechanical property and residual stress investigations of four AA5083 FS welds produced under varying conditions. It was found that the weld properties were dominated by the thermal input (thermal excursion) rather than the mechanical deformation by the tool, resulting in a 30 mm wide zone of equiaxed grains around the weld line. Increasing the traverse speed and hence reducing the heat input narrowed the weld zone. It is observed that the recrystallization resulting in the weld zone had considerably lower hardness and yield strength than the parent AA5083. During tensile testing, almost all the plastic flow occurred within the recrystallized weld zone and the synchrotron residual stress analysis indicated that the weld zone is in tension in both the longitudinal and transverse directions. The peak longitudinal stresses increased as the traverse speed increases. This increase is probably due to steeper thermal gradients during welding and the reduced time for stress relaxation to occur. The tensile stresses appear to be limited to the softened weld zone resulting in a narrowing of the tensile region (and the peak stresses) as the traverse speed increased. Measurements of the unstrained lattice parameter (d0) indicated variations with distance from the weld line that would result in significant errors in the inferred residual stresses if a single value for d0 were used for diffraction based experiment. The evolution of the fine-grained structure in friction-stir processed aluminum has been studied by Rhodes et.al. [8] using a rotating-tool plunge and extract technique. In these experiments, the rotating tool introduced severe deformation in the starting grain structure, including severe deformation of the pre-existing sub-grains. Extreme surface cooling was used to freeze in the starting structure. Heat generated by the rotating tool was indicated as a function of the rotation speed and the external cooling rate. At slower cooling rates and/or faster tool rotation speeds, recrystallization of the deformed aluminum was observed to occur. The initial sizes of the newly recrystallized grains were in the order of 25-100 nm, considerably smaller than the pre-existing sub-grains in the starting condition. Subsequent experiments revealed that the newly recrystallized grains grow to a size (2-5Ãâà µm) equivalent to that found in friction-stir processed aluminum, after heating 1-4 min a t 350-450 Ãâà °C. It is postulated that the 2-5 Ãâà µm grains found in friction-stir welded and friction-stir processed aluminum alloys arose as the result of nucleation and growth within a heavily deformed structure and not from the rotation of pre-existing sub-grains. Sato et.al [9] applied FSW to an accumulative roll-bonded (ARBed) Al alloy 1100. FSW resulted in reproduction of fine grains in the stir zone and small growth of the ultrafine grains of the ARBed material just outside the stir zone. FSW was reported to suppress large reductions of hardness in the ARBed material, although the stir zone and the TMAZ experienced small reductions of hardness due to dynamic recrystallization and recovery. Consequently, FSW effectively prevented the softening in the ARBed alloy which had an equivalent strain of 4.8. The microstructure evolution of a joint of Al-Si-Mg alloys A6056-T4 and A6056-T6 was characterized using transmission electron microscopy (TEM) by Cabibbo et.al. [10]. Metallurgical investigations, hardness and mechanical tests were also performed to correlate the TEM investigations to the mechanical properties of the produced FSW butt joint. After FSW thermal treatment was carried out at 530 Ãâà °C followed by ageing at 160 Ãâà °C (T6). The base material (T4) and the heat-treated one (T6) were put in comparison showing a remarkable ductility reduction of the joint after T6 treatment i.e., it was 80-90% of that of the parent material. The microstructure of a FSW Al-6.0Cu-0.75Mg-0.65Ag (wt.%) alloy in the peak-aged T6 temper was characterized by TEM by Lityska et.al. [11]. Strengthening precipitates found in the base alloys dissolved in the weld nugget, while it was observed that in the heat-affected zone Cu) and s (Althey were coarsened considerably, causing softening inside the weld region. Precipitates of the O (Al2Cu) phase, was considered as the main strengthening phase in base material, grew up to 200-300 nm in the heat-affected zone, but their density decreased. It was observed that they co-existed with F'(Al2Cu), S'(Al2CuMg), F(Al25Cu6Mg2) phases. The density of the F and S phases as well as their sizes increased in comparison to the base material. The high-resolution observation allowed them to compare the morphology of the O phase plates in the heat-affected zone and in the base material. The grain structure, dislocation density and second phase particles in various regions including the dynamically recrystallized zone (DXZ), thermo-mechanically affected zone (TMAZ), and heat affected zone (HAZ) of a FSW aluminum alloy 7050-T651 were investigated and compared with the unaffected base metal by Su et.al. [12]. The various regions were studied in detail to better understand the microstructural evolution during FSW. They concluded that the microstructural development in each region was a strong function of the local thermo-mechanical cycle experienced during welding. Using the combination of structural characteristics observed in each weld region, a new dynamic recrystallization model was proposed. The precipitation phenomena in different weld regions were also discussed. The laser beam and friction stir processes were applied to the ECA pressed Al alloy 1050 with the thickness of 1 mm by Sato et.al. [13]. The ECA pressed alloy after two passes through the die consisted of cell structure with cell size of about 0.58 Ãâà µm, and the hardness value was approximately 46 Hv. The LBW produced as-cast coarse microstructure and coarse equiaxed grain structure at the fusion zone and the HAZ respectively, which led to the hardness reduction to
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