Manufacturing Engineering & Technology
7th Edition
ISBN: 9780133128741
Author: Serope Kalpakjian, Steven Schmid
Publisher: Prentice Hall
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Textbook Question
Chapter 2, Problem 30QLP
Explain why materials with high m values, such as hot glass and Silly Putty®, when stretched slowly, undergo large elongations before failure. Consider events taking place in the necked region of the specimen.
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Chapter 2 Solutions
Manufacturing Engineering & Technology
Ch. 2 - Distinguish between engineering stress and true...Ch. 2 - In a stress-strain curve, what is the proportional...Ch. 2 - Describe the events that take place when a...Ch. 2 - What is ductility, and how is it measured?Ch. 2 - In the equation =Kn, which represents the true...Ch. 2 - What is strain-rate sensitivity, and how is it...Ch. 2 - What test can measure the properties of a material...Ch. 2 - What testing procedures can be used to measure the...Ch. 2 - Describe the differences between brittle and...Ch. 2 - What is hardness? Explain.
Ch. 2 - Describe the features of a Rockwell hardness test.Ch. 2 - What is a Leeb test? How is it different from a...Ch. 2 - Differentiate between stress relaxation and creep.Ch. 2 - Describe the difference between elastic and...Ch. 2 - Explain what uniform elongation means in tension...Ch. 2 - Describe the difference between deformation rate...Ch. 2 - Describe the difficulties involved in conducting a...Ch. 2 - What is Hookes law? Youngs modulus? Poissons...Ch. 2 - Describe the difference between transgranular and...Ch. 2 - What is the reason that yield strength is...Ch. 2 - Why does the fatigue strength of a specimen or...Ch. 2 - If striations are observed under microscopic...Ch. 2 - What is an Izod test? Why are Izod tests useful?Ch. 2 - Why does temperature increase during plastic...Ch. 2 - What is residual stress? How can residual stresses...Ch. 2 - On the same scale for stress, the tensile true...Ch. 2 - What are the similarities and differences between...Ch. 2 - Can a material have a negative Poissons ratio?...Ch. 2 - It has been stated that the higher the value of m,...Ch. 2 - Explain why materials with high m values, such as...Ch. 2 - With a simple sketch, explain whether it is...Ch. 2 - Explain why the difference between engineering...Ch. 2 - Consider an elastomer, such as a rubber band. This...Ch. 2 - If a material (such as aluminum) does not have an...Ch. 2 - What role, if any, does friction play in a...Ch. 2 - Which hardness tests and scales would you use for...Ch. 2 - Consider the circumstance where a Vickers hardness...Ch. 2 - Which of the two tests, tension or compression,...Ch. 2 - List and explain briefly the conditions that...Ch. 2 - List the factors that you would consider in...Ch. 2 - On the basis of Fig. 2.5, can you calculate the...Ch. 2 - If a metal tension-test specimen is rapidly pulled...Ch. 2 - Comment on your observations regarding the...Ch. 2 - Will the disk test be applicable to a ductile...Ch. 2 - What hardness test is suitable for determining the...Ch. 2 - Wire rope consists of many wires that bend and...Ch. 2 - A statistical sampling of Rockwell C hardness...Ch. 2 - In a Brinell hardness test, the resulting...Ch. 2 - Some coatings are extremely thinsome as thin as a...Ch. 2 - Select an appropriate hardness test for each of...Ch. 2 - A paper clip is made of wire 0.5 mm in diameter....Ch. 2 - A 250-mm-long strip of metal is stretched in two...Ch. 2 - Identify the two materials in Fig. 2.5 that have...Ch. 2 - Plot the ultimate strength vs. stiffness for the...Ch. 2 - If you remove the layer of material ad from the...Ch. 2 - Prove that the true strain at necking equals the...Ch. 2 - Percent elongation is always defined in terms of...Ch. 2 - You are given the K and n values of two different...Ch. 2 - A cable is made of two strands of different...Ch. 2 - On the basis of the information given in Fig. 2.5,...Ch. 2 - In a disk test performed on a specimen 1.00 in. in...Ch. 2 - A piece of steel has a hardness of 300 HB....Ch. 2 - A metal has the following properties: UTS = 70,000...Ch. 2 - Using only Fig. 2.5, calculate the maximum load in...Ch. 2 - Estimate the modulus of resilience for a highly...Ch. 2 - A metal has a strength coefficient K = 100,000 psi...Ch. 2 - Plot the true stresstrue strain curves for the...Ch. 2 - The design specification for a metal requires a...Ch. 2 - Calculate the major and minor pyramid angles for a...Ch. 2 - If a material has a target hardness of 300 HB,...Ch. 2 - A Rockwell A test was conducted on a material and...Ch. 2 - For a cold-drawn 0.5% carbon steel, will a...Ch. 2 - A material is tested in tension. Over a 1-in. gage...Ch. 2 - A horizontal rigid bar cc is subjecting specimen a...Ch. 2 - List and explain the desirable mechanical...Ch. 2 - When making a hamburger, you may have observed the...Ch. 2 - An inexpensive claylike material called Silly...Ch. 2 - In tension testing of specimens, mechanical and...Ch. 2 - Demonstrate the impact toughness of a piece of...Ch. 2 - Using a large rubber band and a set of weights,...Ch. 2 - Find or prepare some solid circular pieces of...Ch. 2 - Take several rubber bands and pull them at...Ch. 2 - Devise a simple fixture for conducting the bend...Ch. 2 - By pressing a small ball bearing against the top...Ch. 2 - Describe your observations regarding Fig. 2.14c.Ch. 2 - Embed a small steel ball in a soft block of...Ch. 2 - Devise a simple experiment, and perform tests on...Ch. 2 - Obtain some solid and some tubular metal pieces,...Ch. 2 - Explain how you would obtain an estimate of the...Ch. 2 - Without using the words stress or strain, define...Ch. 2 - We know that it is relatively easy to subject a...
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