...periods of time with little or no maintenance. The material used for these equipment are to be made of brass plate because it is good corrosion resistance, easy machining tough. The question seeking for an answer of the investigation is “Can buying brass ingot and roll it flat to get a 60 percent reduction in thickness and hardness of 45 without it cracking?” For this experiment, there was two test that was conducted, Cold Working test and the Heat Treatment Test, on a sample of 260 Brass in ingot form. For the Cold Working Test, the first done was putting the sample through a Stanat Rolling Mill to reduce the thickness of the ingot. Part two of the Cold Working Test was to use the Rockwell Hardness Tester to measure the hardness of Brass. Do this test ten times at increments of -0.75 from 10.5mm to 3mm. At each targeted thickness, measure the width and length. The result of the test is on Table 1. After doing the Cold working Test, Heat treatment test is done. For this test, take the 3mm brass plate and cut it into 5 equal pieces and place each piece into the5 furnaces at 100°C, 260°C, 350°C, 450°C, and 565°C. Test the Hardness of each piece on the Rockwell Hardness Tester and the results are on Table 2. After conducting this experiment, the answer to “Can...
Words: 1903 - Pages: 8
...study the effects of cold working on the microstructure and mechanical properties of 70/30 Cartridge Brass. Background A small percentage of the energy expended in plastically deforming a material remains stored in the metal as an increase in internal energy. Changes are produced in both its physical and mechanical properties. Principally, there is a marked increase in hardness and electrical resistivity with the amount of cold working. Microstructurally, this increment in internal energy is associated with an increase in the dislocation density as well as the density of point defects, such as vacancies and interstitials. For most metals, the dislocation density increases from the values of 106-107 lines/cm2 (typical of the annealed state) to 108-109 after a few percent deformation and up to 1011 -1012 lines/cm2 after heavy deformation. At a more macrostructural level, the grains become markedly elongated in the direction of working and heavily distorted. This distortion is evident from a bending of annealing twins and from unevenness in etching caused by local strain inhomogeneities. While the increased hardness and strength that result from the working operation can be important, it is often necessary to return the metal to its initial condition by annealing. This usually means holding the cold worked metal at a temperature above about 1/3 of the absolute melting point for a period of time. The annealing treatment is divided into three distinct regions: 1. Recovery: This usually...
Words: 1487 - Pages: 6
...1mm intervals from the outer edge for 1.0mm, and then at 0.5mm intervals for an additional 3.0mm. A complete set of procedural steps is available in the Appendix section of this lab report. Theoretical Results: Throughout the process of any experiment, it is a necessity to understand the data that is gathered. Knowing this, a direct comparison between carburized and decarburized steel is necessary. Referring to the appendix section, Figure 1a displays the relationship between hardness of the material and the distance from the edge. It is apparent that the relationship between these two qualities is inversely proportional; meaning that as distance is increased, the hardness begins to decrease. However, when referring to Figure 1b, it holds true that an opposite trend occurs. When observing Figure 1b, one can see that with an increase in distance, an increase in hardness directly correlates as well. The visual layer of the carburization can be found from the graph by determining where the hardness drops off and remains at a constant trend line. Using this method, an estimated visual layer of depth is approximately 170μm. Referring to the same figure, the end of the useful layer can be determined as...
Words: 1288 - Pages: 6
...samples, ‘as is’ and ‘quenched’, are tested for hardness using the Vickers method. The data obtained from these samples was, ‘as is’ HV204.9 and ‘quenched’ 472.0’. This quantified data has been analysed and discussed. Comparisons of this data have been made, and have led to a conclusion, that is clearly visible with scrutinising. This conclusion shows us that the hardening of a suitably high in carbon steel by the method of quenching is an extremely efficient method. Further testing would be recommended. Table of contents Aim: 2 Introduction: 2 Method: 2 Results: 3 Table 1 Graph 1 Graph 2 Discussion: Conclusion: Bibliography/References: AIM: The aim of this practical is to compare and contrast the mechanical properties of a high carbon steel in two conditions. These are quenched and as delivered. INTRODUCTION: Please refer to the class handout attached as ‘Appendix 1’. METHOD: Please refer to the class handout attached as ‘Appendix 1’. RESULTS The results of this Lab Practical on heat treatment provides an informative and clear result. The two samples tested, ‘as is’ and ‘quenched’, and the data obtained from the testing of these two samples, clearly demonstrate the differences between a heat treated object and a non-heat treated object. This data will be used to make two comparisons: Firstly, the results from the Vickers Hardness Test will be looked at and a comparison made. By...
Words: 786 - Pages: 4
...introduced determines the hardness and other material properties of the finished product. The advantages of cold rolling are good dimensional accuracy and surface finish. Cold rolled sheet can be produced in various conditions such as skin-rolled, quarter hard, half hard, full hard depending on how much cold work has been performed. This cold working (hardness) is often called temper, although this has nothing to do withheat treatment temper. In skin rolling, the metal is reduced by 0.5 to 1% and results in a surface that is smooth and the yield point phenomenon--excessive stretching and wrinkling in subsequent operations, is eliminated. This makes the metal more ductile for further forming and stretching operations. Quarter Hard, Half Hard, Full Hard stock have higher amounts of reduction, upto 50%. This increases the yield point; grain orientation and material properties assume different properties along the grain orientation. However, while the yield point increases, ductility decreases. Quarter Hard material can be bent (perpendicular to the direction of rolling) on itself without fracturing. Half hard material can be bent 90º; full hard can be bent 45º. Thus, these materials can be used for in applications involving great amounts of bending and deformation, without fracturing. Annealing, in metallurgy and materials science, is a heat treatment wherein a material is altered, causing changes in its properties such as strength and hardness. It is a process that produces...
Words: 363 - Pages: 2
...aluminium alloys:- i.1xxx – PURE ALUMINIUM (OVER 99% PURE) ii.2xxx - COPPER iii.3xxx - MANGANESE iv.4xxx - SILICON v.5xxx - MAGNESIUM vi.6xxx – MAGNESIUM AND SILICON vii.7xxx - ZINC viii.8xxx – SPECIAL ALLOYING ELEMENT ix.9xxx – UNUSED SERIES 3. There are 3 types of hardness test available. Explain what is the type of penetrator used and how to measure harness for each method. i.Brinell hardness test –In this method, a hardness steel ball is pressed into the surface of the tested material at a specified load for specified period of time -The result taken is the measurement of ball indentation diameter, so determining the hardness of the material ii.Rockwell hardness test –The diamond cone is used as penetrator. -Result from the depth of penetration of the diamond cone to the surface of the material will determine the hardness of the matterial iii.Vickers hardness test –The penetrator is a square-based diamond pyramid shaped -The penetrator is forced onto the materials surface and measurement is taken on the cross-section of the square impression to determine the hardness of the...
Words: 251 - Pages: 2
...Shorter soaking times can be used during an annealing heat treatment if an increase in material hardness and less ductility is desired. 2. The micrometer was used to measure the cross-sectional dimensions of the steel before and after the heat treatment and values where recorded as shown in Table 3. And it was observed that there was an increase in the workpiece (steel) size after the heat treatment when compared with the dimensions before the heat treatment as shown in Table 3, this simply means that there was an increase in ductility after the heat treatment was performed. 3. In terms of mechanical properties after this heat treatment, a softer material was obtained, there was an increase in ductility which improves machinability and formability. If a slightly harder workpiece is desired, the workpiece should be: * Heated to the austenite phase and then quenched with water or oil. This rapid cooling results in a hard and brittle workpiece. * The soaking time should be shorter. Table 1. The Rockwell B Hardness for the steel before and after treatment Rockwell B Hardness Before Heat Treatment (HRB-1) | Rockwell B Hardness After Heat Treatment (HRB-2) | 53.9 | 41.4 | 58.6 | 44.6 | 63.4 | 44.6 | 59.2 | 43.3 | 61.1 | 45.2 | 67.3 | 47.8 | 58.2 | 48.5 | 64.7 | 45.9 | 64.9 | 42.9 | Table 2. The Mean and Standard deviation of the Rockwell B hardness values in Table 1...
Words: 711 - Pages: 3
...Lab Assignment Part A – Analysis of Literature Data 1. Proof Stress vs Cold Work 600 500 Proof stress (MPa) 400 15µm 300 200 100 0 0 10 20 30 40 50 60 70 Cold work (%) 70µm Sample 5 - 15µm Sample 5 - 70µm Figure 1 – Proof Stress vs Cold Work of 70/30 Brass As can be seen from Figure 1, the 0% cold worked points (Sample 5) for each grain size is in line with the curve of the other four points. The amount of proof stress increases with increased cold work, but approaches an asymptote at a point of maximum increase in proof stress. Cold working uses processes such as drawings to deform the grains in a material, thereby increasing the proof stress of the material. 2. (i) Grain size strengthening is a process that reduces the sizes of the grains in a material, typically by annealing. This works to increase the strength of the material through the fact that grain boundaries act as a barrier to dislocations. As can be seen in Figure 1, decrease in grain size causes an increase in proof stress. Cold working involves plastically deforming a material such that dislocations become concentrated. These dislocations then become entangled, hindering further dislocation movement, thereby increasing the strength of the material. As can be seen in Figure 1, proof stress can be increased dramatically by cold work hardening, but only to a point. (ii) Grain size strengthening and cold work hardening can be used together to form a much stronger material. Grain size strengthening reduces...
Words: 2479 - Pages: 10
...are altered through drawing, extruding, hammering, pressing, rolling, spinning, and stretching at temperatures below the steel's recrystallization point, usually room temperature. These processes result in changes to the metal's composition which permanently increases its hardness and tensile strength, and improve the surface finish, but decrease ductility and impact resistance. After hot rolling, many steel products undergo a further processing in the cold state. This stage of processing may not necessarily alter the shape of the steel, but it does reduce its thickness and significantly improve its performance characteristics. Hot rolled coil is commonly known as cold rolled, also known as cold reduced. Cold rolling is a process by which the sheet metal or strip stock is introduced between rollers and then compressed and squeezed. The amount of strain introduced determines the hardness and other material properties of the finished product. The advantages of cold rolling are good dimensional accuracy and surface finish. Cold rolled sheet can be produced in various conditions such as skin-rolled, quarter hard, half hard, full hard depending on how much cold work has been performed. This cold working hardness is often called temper, although this has nothing to do with heat treatment temper. Quarter Hard, Half Hard, Full Hard stock have higher amounts of reduction, up to 50%. This increases the yield point; grain orientation and material properties undertake different properties...
Words: 621 - Pages: 3
...1. Do you think there is a trade-off between the positive (high performance) and negative (increased stress) effects of stretch goals? Setting goals is part of organizational life and a powerful way to keep employees aligned and clear about expectations. But how tough should the goals be? How high should you set the bar? Some leaders like to set goals at a low to moderate level, based on the concept that they want everyone to be successful. They believe that success increases employee motivation and satisfaction. A second approach is to set the goals fairly high, expecting that a good portion of the employees will achieve them, but everyone has to work pretty hard to be successful. The third approach is to make the goals so high that only the very best performers might attain them, but not too often. This is based on the premise that if you set the bar really high then everyone will work their hardest to go as far as they can. However, stretch goals can have a tradeoff between the positive and negative effects. On the positive side, it can increase high work performance since it enables employees to reach their fullest potential. Sometimes employees find stretch goals very motivating and make it a challenge to attain it, because managers generally attach incentives such as recognition and other forms of rewards for attaining these goals. Nevertheless, stretch goals also have negative effects and this is the stress that employees go through when unrealistic goals are set by...
Words: 324 - Pages: 2
...1. Do you think there is a trade-off between the positive (high performance) and negative (increased stress) effects of stretch goals? Setting goals is part of organizational life and a powerful way to keep employees aligned and clear about expectations. But how tough should the goals be? How high should you set the bar? Some leaders like to set goals at a low to moderate level, based on the concept that they want everyone to be successful. They believe that success increases employee motivation and satisfaction. A second approach is to set the goals fairly high, expecting that a good portion of the employees will achieve them, but everyone has to work pretty hard to be successful. The third approach is to make the goals so high that only the very best performers might attain them, but not too often. This is based on the premise that if you set the bar really high then everyone will work their hardest to go as far as they can. However, stretch goals can have a tradeoff between the positive and negative effects. On the positive side, it can increase high work performance since it enables employees to reach their fullest potential. Sometimes employees find stretch goals very motivating and make it a challenge to attain it, because managers generally attach incentives such as recognition and other forms of rewards for attaining these goals. Nevertheless, stretch goals also have negative effects and this is the stress that employees go through when unrealistic goals are set by...
Words: 324 - Pages: 2
...When Capitalism is Great and Not-so-great Reflection To me I feel that both sides of government and socialism are decent and working. But overall I on not think they are efficient or anywhere close to effective as they should be. I feel that there should be an idea council or rep team for a better government. Also I felt as if we are a little one sided on Capitalism and never were really taught as a nation all the possibilities that could help us in the long run. To me the development of a better government, a better America is in question because I don’t know about it do you? I was intrigued by the thought of “fairness”, in theory both sides had that element of fairness. Capitalism has great incentives for determination and hard work , it really polarizes the “pay off” if you can make it that far. I feel it is a delicate situation but I think to a degree the start off point of life in America can undermine the hard work it takes to get to the pay off, as far as location and living situations I feel the main reason countries are ahead of us in innovation and education is that they support the youth entirely , not as many countries with a socialism government have children staving work at a young age, worry about living conditions struggling every day to support their selves , family or whatever situation you can pull out of your head that puts the youth’s back to the wall. Now there are thousands of great stories of people becoming great and overcoming the lowest of the...
Words: 343 - Pages: 2
... New jobs can be tough and require a lot of work, effort, and perseverance. In the Call of the Wild, Buck gets his first job, Spitz fell into the ice and almost dragged the whole team in. Buck persevered and tried his hardest to drag the team out of the ice. In contrast to Buck, my dad persevered when he got his new job, and the company downsized. Since my dad was one of the new reps they had to let him go. But he was stubborn and never gave up looking for a job. Buck had to persevere through the hard times even when Perrault and Francois sold him. My dad had to persevere even though he lost his job. My dad was stubborn and never gave up. But he also had a newborn baby to feed and a new house to pay for. Buck was sold and kept working hard and doing what he thought was right. Altogether we all have something we persevere through, it could be something from really big to something really small. In The Call of the Wild, Buck’s new job is tough and he has to change his old life, from being carefree, to being carefull and using his instincts. Buck has to persevere through the hard times of his new job. In the book Buck is put on a new team and has to conquer the rough, and cruel events with the lead dog, Spitz. The dogs are put to work, and each day they have to haul heavy loads of mail, for thousands of miles. When they set up for camp, Buck and his team barely get any food to eat. Buck learns to steal food, so that he wouldn’t be hungry anymore. After many tiring days the...
Words: 868 - Pages: 4
...Tabitha West The Social Mirror Assignment 1. What would others say about you that is generally positive? Friends would actually say I am very kind hearted, loving, and caring. I take care of my family and protect the ones that I love. I try my hardest to please everyone but I get stepped on. My sister would say I am to kind for my own good but I am a hard worker and I do not give up very easily. 2. What “constructive suggestions” would others offer to help you improve or change? My sister would offer me a back bone, to stand up when need be especially to my family, also more of what she would call a better leg to stand on. My friends say they like me for who I am and would not change it at all except better taste in men. 3. What do you most like about yourself? I like most about myself I am a very caring person, I do my best to make everything right or be there for someone. I am currently taking care of my grandmother while the rest of the family kind of expects me to with my background and I live here. I do it because I love her and no one else will they don’t care. 4. What do you most dislike in yourself and would like to change? What I dislike about myself the most, that I have a big heart. People with big hearts seem to get pushed around and stepped on or is that just me? It seems the bigger the heart the easier to break in my life. People take for granted that I am kind and loving and use it to their advantages. 5. What beliefs to you have about yourself that...
Words: 644 - Pages: 3
...As I reminisce a year back when I undergone the Peer Counseling Training, I proudly take into account the knowledge I congregated as a product of that noble event. Here I am again to answer this kind of question confronting my whole personality. Before, as I spent my time with the counselors, I was asked with the same question. To be honest, it's really hard to know one self but it is necessary. For you to know others know yourself. To understand others understand yourself. But it takes time to accomplish because you need to know everything with in you, accept it, and learn with it. I am Kestrel. Behind this name, I am who's on the process and still not perfectly molded as well-rounded individual. I am who look forward towards my goal, is a person with dark spots and discouragement. I am adventurous and I love to discover unusual things but I am afraid of what I don't know. I am important but I am unknown. If I were to put my self on the field, I am a farmer plowing my own lifeless stalks. I had with me this attitude, willing to take the challenge but afraid. Maybe or really I am just low self-esteemed. It is easy to say that I am kind, I am affectionate, I am honest, I am positive. The hardest thing there is to accept that behind those sunny aspects of mine, I am still facing the mirror of darkness and I don't know how to conquer it. This is me. I am positive but my negative side is pulling me down to failure. I always put into my mind that I must think hopefully, speak...
Words: 427 - Pages: 2
