...Metal forming is a general term, for a large group, that includes a wide variety of manufacturing processes. Metal forming processes are characteristic in that the metal being processed is plastically deformed in order to shape it into a desired geometry. In order to plastically deform a metal, a force must be applied that will exceed the yield strength of the material. The material actually gets stronger the more it is deformed plastically. This is called strain hardening or work hardening. Many metal forming processes are suitable for processing large quantities (i.e., bulk) of material, and their suitability depends not only upon the shape and size control of the product but also upon the surface finish produced. There are many different metal forming processes and some processes yield a better geometry and surface-finish than some others. Metal forming processes can be classified under two major groups. Bulk deformation processes and sheet metalworking processes. Bulk deformation is characteristic in that the work formed has a low surface area to volume ratio. In sheet metalworking the metal being processed will have a high surface area to volume ratio. Among the bulk Deformation, there are rolling, forging, extrusion and drawing method. Rolling is a metal forming process that deforms the work by the use of rolls. Rolling processes include flat rolling, shape rolling, ring rolling, thread rolling, gear rolling, and the production of seamless tube and pipe by rotary...
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...MCP 232 Lab Report Aim: To study the work hardening change in hardness in cold rolling operation Material: Low carbon steel Method of Test: 1. Rolling Treatment 2. Indentation Hardness test Observations: Rolling Treatment Least Count of micrometer= 0.001mm Specimen 1 Thickness= 2+ 48x0.001= 2.048mm S.No. | F1 (kN) | F2 (kN) | Total Force (kN) | 1. | 14 | 12.02 | 26.02 | 2. | 15.55 | 16.02 | 31.57 | * 5% reduction in each pass * Total thickness reduction= 10% Specimen 2 Thickness= 1.85mm S.No. | F1 (kN) | F2 (kN) | Total Force (kN) | 1. | 18.7 | 19.5 | 38.2 | 2. | 19.3 | 19.48 | 38.78 | 3. | 20.36 | 20.36 | 40.72 | * 5% reduction in each pass * Total thickness reduction= 15% Specimen 3 Thickness= 1.5+ 44x0.001= 1.544mm S.No. | F1 (kN) | F2 (kN) | Total Force (kN) | 1. | 20.9 | 20.6 | 41.5 | 2. | 20.8 | 20.64 | 41.44 | 3. | 20.04 | 20.33 | 40.37 | 4. | 21.7 | 21.96 | 43.66 | 5. | 21.03 | 20.34 | 41.37 | * 3% reduction in each pass * Total thickness reduction= 15% Specimen 4 Thickness= 1.4+0.006=1.406mm Indentation Hardness test Indentation Force=20N Specimen 1: I. 154HV II. 157HV III. 157HV Average Hardness= 157 HV Specimen 2: I. 162HV II. 160HV III. 159HV Average Hardness= 160.33 HV Specimen 1: I. 169HV II. 174HV III. 174HV Average Hardness= 172.33 HV Specimen 1: I. 184HV II. 183HV III. 181HV Average...
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...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 the size of grains whilst cold work hardening increases the grain size and decreases ductility. The combination of these two processes cancels the negative effects of each other. B1. Using the Hall-Petch equation: = Calculations: 193.06 ∴ = = 15 + − 15 − 1 + 193.06 110.32 ∴ Equating (1) and (2): 193.06 15 70 × 193.06 − − = = 70 + − 70 − 2 110.32 = 110.32 70 − =...
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...Cold Rolling Jeffry S. Asher DT1410 Unit 4 Assignment 2 ITT Technical Institute January 18, 2016 Cold rolling is a metal forming process in which the shape and the structure of steel 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...
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...Experiment 5 - Cold Work, Recovery, Recrystallization and Grain Growth Objective To 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...
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...Cold Working of Brass Kevin Louie MatE 25 October 20, 2014 | Marine Research Corporation | To: | Irene Huang | From: | Kevin Louie | Date: | September 29, 2014 | Re: | Determination on whether brass ingot can be used instead of plate form for a motor bracket application. | | | In response to the assigned investigation for Equipment used in the Oceanographic Research Platforms in the Arctic region, the following observation and test were performed. The scenario is having Research equipment installed on the Research Platforms that can survive harsh marine environments while operating for long 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...
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...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 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...
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...¬¬¬Production of the Connecting Rod Drop Forged Connecting Rods Connecting rods are most commonly drop forged, firstly a blank steel bar with a rectangular or round cross section, it is heated to around 1300°C and is rolled to redistribute the masses to the larger and smaller ends. The most important part of the process takes place in a hammer unit, the steel rod is placed in a die and after a few consecutive blows of a hammer the steel bar is forced into the shape of the die, giving the connecting rod its shape. Drop forging produces flash around the edges of the connecting rod which is removed, the larger hole and sometimes the smaller hole (in larger connecting rods) are also simultaneously punched in this process. After the flash is removed the connecting rod is heat treated and then machined, the final stage of the process is the separation of the cap from the rod (unless the cap and the rod have been forged separately), this is usually done by sawing but an alternative is to use splitting. Alternative methods of production A newer technology called Sintering is becoming more popular to produce control rods; it begins with the sevrohydraulic pressing of powdered metal in its final alloy, to create a powdered preform of the control rod. Next the preform is heated to around 1120°C in an electrically heated furnace for around 15 minutes, the finished piece is now ready. The reason this technology has not taken the place of the drop forging process is because...
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...The Dewey Bozella Story It can take some people many years to accomplish a dream; Dewey Bozella was one of those people. Mr. Bozella lived a very hard life, at the age of eight he saw his father beat his pregnant mother to death and at age sixteen his brother was stabbed to death in a fight. He then entered into the foster system and a life of petty crime. This was not a very good start at life in which he had so much going against him. At age seventeen he moved upstate New York to start a life which would involve boxing but instead he began an ordeal that would last twenty-six years. On June 14, 1977 a 92-year old woman was brutally attacked and murdered in her house. There was much pressure on the police and the district attorney to solve this crime. It wasn’t until 1983, a time in which he was turning his life around, that a tip from two of the suspects, who were convicts, would bring Dewey’s name into question. At age eighteen Dewey would be charged with murder. There was no physical evidence and that should have been the end of the case, but he was convicted based on testimony from two convicted felons. It wasn’t until 1990 that he was able to get a retrial due to the fact that his civil rights were violated. But again the jury found him guilty and he would return to prison. In prison he was able to get a bachelor’s degree as well as a master’s degree. He also had the opportunity to take up boxing, something he thought her would never get a chance to do. During...
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...REACTION PAPER At the age of 16, what are you doing at this age? Ordinary teenagers at this age used to go to school particularly high school, and enjoy their teenage years. Aside from this routine, teenagers may earn money by different stuffs around them. Most of the teenagers enjoy playing online computer games as for now. And who knows you can use this stuff to earn money and lead your first step to become a successful entrepreneur or I should say technopreneur. Like Ittipat who is now a successful businessman. I just can’t imagine how these young people became successful in their life in a simple way like using technology. Ittipat made his first step when someone offer the money to buy the equipment of the online game he was addicted. Of course that way is illegal but he does not think the risk about that. Maybe this is the starter for Top to think about the business. But likes the other gamer addictive he forget his duty as a student, always playing game every day. Because of that he always get low score in his school and he didnt make up to enter state university of Thailand. Until his account became unable to use because of the transaction that he did in the game. And one day when he bought some DVD units but he was cheated by the seller of the DVD. But he didn’t give up. He try other business and like the other successful businessman, he went through many struggles in life like his family go to Shanghai because of the debt in bank, broke up with her girlfriend and many...
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... has gone on through the centuries. In this country it was with the beginnings of rock and roll and has continued on today. Rock music is huge when it comes to censorship because of the allusion to sex, drugs, alcohol, and violence. The Government believes that profanity is what they need to censor people from, though the freedom of speech is a First Amendment right to all people. The Government sees it as what the average person would find offensive and lacks any serious value in literature, artistic, political, or scientific. It is the sexually explicit and violent material in the songs that makes it so a person has to be a certain age before they can buy a CD with this type of music. This is why many parents have to buy the CD’s that their children like. Many have found out in after doing research that this is a strictly state by state policy. There are families that have witness this because they have lived in different states, they can tell the difference from one to another. There are stores that also refuse to carry any music which can be offensive, even though they sell...
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...so that we can capitalize on it. Since Macy’s, Inc has a long standing tradition of believing that giving back is the right thing to do (Macy's Inc, 2011) , we would like to help Kava try to recover from all the disasters they have gone through, and help to overcome the challenges that they are now facing. Macy’s will do this by addressing the issues found in the business scenario, forces involved in the formulation of the problem, and organizational and environmental obstacles impacting key stakeholders. After looking at the business scenario and seeing what the director of strategic planning had to say, it was easy to see what issues are present. Challenges now facing the island of Kava are 1) over 50% of the population are under the age of 15 years old; 2) the ethnic mix of languages and cultures indigenous to the South Pacific area of Kava; and 3) the economy for which the natives of Kava depend is constantly threatened by natural disasters such as tsunami,...
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... | |Pattern of Health Perception and Health | | |. | |Management: |1. Dependent upon parents and caregivers|1. Normal Heart Rate is 40-70 beats |1. Ability to accept responsibility for | | |for teaching, modeling perceptions and |per minute. |some aspects of personal care. | |List two normal assessment findings that |good practices where health care is |2. Curiosity regarding the body and the|2. Self-dental care. | |would be characteristic for each age |concerned. |opposite sex. |3. Physical growth slows. | |group. |2. Routine check-ups and immunizations. |3. Familiar with the part of the body |...
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...What impacts the behaviors of individuals? There are several characteristics that contribute to this such as age, attitude, education and gender. How do these impact each other in the work place? Diversity plays a large role in the work place, many people working together daily and having to deal with many things that they may not agree with. Age Age impacts people in a few ways there is stereotyping, ageism and discrimination. Many workers that are over the age of 40 are considered ‘old’ and these people are thought to be ‘set in their ways’ and not willing to chance. This is not necessarily the truth, but they are more likely to be seen this way, this causes more discrimination and in turn more law suits. A perfect example of this is my father-in-law. He is in his 70’s and has been retired for 8 years, but he likes to work a couple of days a week to keep himself active. The move from another state proved to be very difficult for him to find work; he looked for 7 months before he was actually able to find work. This may not be because of his age, but he has been working for over 50 years finding a job one would think would be somewhat easy. Attitude Attitude impacts individuals in the workplace in one of two ways either negative or positive. One that has a positive attitude in the work place going to be do better at the job, whereas a person that has a negative attitude is more likely going to work as little as they can. One of the best ways to have a positive attitude...
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...ascertain the age of N.O. As set out in Regina V. SLATER in the Saskatchewan court of appeal (2005) * appeal was denied because the crown proved that slater had not taken all the reasonable steps to ascertain the ages of his victims. * We believe that our client did indeed take all the reasonable steps to determine age before engaging in sexual activity with N.O. The first step outlined by Justice Jackson was Physical appearance. In relation to this step the defense would like to introduce exhibits A & B 1st slide: Notice the similarities of exhibit A to our complainant, she has large breasts and fits into the category of a 34-22-30 measurement. 2nd slide: Although exhibit B has smaller breasts she still fits into the same category as N.O. So put yourself in the shoes of our client, now can you guess how old she is? The next reasonable step that Justice Jackson pointed out was…Behaviour the fact that N.O. was observed drinking alcohol& smoking marijuana at a biker bush party can be used as relevant information pertaining to Chester’s belief that N.O. was not actually 13 In relation to our case The third step stated was…. The ages and appearances of those whose company the complaint has been found in…on this particular night N.O. had been found in the presence of bikers. it is reasonable to assume that to a be a biker one must hold a valid driver’s license. This makes majority of bikers hypothetically attending this party well above the age of consent. ...
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