Degarmo's Materials And Processes In Manufacturing
13th Edition
ISBN: 9781119492825
Author: Black, J. Temple, Kohser, Ronald A., Author.
Publisher: Wiley,
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Chapter 3, Problem 4P
Polyethylene consists of fibrous molecules of covalently bonded atoms tangled and interacting like the fibers of a cotton ball. Weaker van der Waals forces act between the molecules with a strength that is inversely related to separation distance.
- What properties of polyethylene can be attributed to the covalent bonding?
- What properties are most likely the result of the weaker van der Waals forces?
- If we pull on the ends of a cotton ball, the cotton fibers go from a random arrangement to an array of somewhat aligned fibers. Assuming we get a similar response from deformed polyethylene, how might properties change? Why?
- Would the properties of the deformed polyethylene be isotropic or anisotropic?
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Question (3):
At a temperature of 5°C, 3 mm gap exists between two polymer bars and rigid support, as shown
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Fig. 3
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3-mm gap
50 mm
700 mm
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B
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Increasing the temperature of a semiconductor breaks covalent bonds. For each broken bond, two electrons become free to move and transfer electrical charge. What fraction of the total valance electrons are free to move and what fraction of the covalent bonds must be broken in order that 5×1015 electrons conduct electrical charge in 50 g of silicon?
Chapter 3 Solutions
Degarmo's Materials And Processes In Manufacturing
Ch. 3 - What enables us to control the properties and...Ch. 3 - Â What are the next levels of structure that are...Ch. 3 - Prob. 3RQCh. 3 - Prob. 4RQCh. 3 - Prob. 5RQCh. 3 - Prob. 6RQCh. 3 - What are the three types of primary bonds, and...Ch. 3 - What are some general characteristics of...Ch. 3 - Prob. 9RQCh. 3 - Prob. 10RQ
Ch. 3 - Prob. 11RQCh. 3 - Prob. 12RQCh. 3 - Prob. 13RQCh. 3 - What are some unique property features of...Ch. 3 - Prob. 15RQCh. 3 - Prob. 16RQCh. 3 - Prob. 17RQCh. 3 - What are some of the general characteristics of...Ch. 3 - Prob. 19RQCh. 3 - Prob. 20RQCh. 3 - Prob. 21RQCh. 3 - Prob. 22RQCh. 3 - Prob. 23RQCh. 3 - Prob. 24RQCh. 3 - What is a grain? A grain boundary?Ch. 3 - Prob. 26RQCh. 3 - What is implied by a low ASTM grain�size number?...Ch. 3 - Prob. 28RQCh. 3 - What is Poissons ratio, and under what conditions...Ch. 3 - What is plastic deformation?Ch. 3 - Why do metals retain their strength during plastic...Ch. 3 - Prob. 32RQCh. 3 - Prob. 33RQCh. 3 - What is a dislocation? Using the carpet analogy,...Ch. 3 - What is the difference between an edge dislocation...Ch. 3 - What are some of the common barriers to...Ch. 3 - Prob. 37RQCh. 3 - What is the mechanism (or mechanisms) responsible...Ch. 3 - Why is a fine grain size often desired in an...Ch. 3 - What is an anisotropic property? Why might...Ch. 3 - What is the difference between brittle fracture...Ch. 3 - How does a metal increase its internal energy...Ch. 3 - What is required in order to drive the...Ch. 3 - How might the lowest recrystallization temperature...Ch. 3 - In what ways can recrystallization be used to...Ch. 3 - What is the major distinguishing feature between...Ch. 3 - What is warm working?Ch. 3 - How can deformation and recrystallization improve...Ch. 3 - Why is grain growth usually undesirable?Ch. 3 - Prob. 50RQCh. 3 - As a result of their ionic or covalent bonding,...Ch. 3 - Prob. 52RQCh. 3 - Prob. 53RQCh. 3 - What is the difference between an intrinsic...Ch. 3 - What is required for electrical conductivity in...Ch. 3 - What is required for electrical conductivity in...Ch. 3 - Brass is an alloy of copper with a certain amount...Ch. 3 - It is not uncommon for processing operations to...Ch. 3 - Polyethylene consists of fibrous molecules of...Ch. 3 - Prob. 5P
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