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Unformatted text preview: Please print a copy, complete, and turn in on April 19, 2006 at the beginning of class. Name /50 101: Modern Materials and Society, Spring, 2006 HW #3, Chapters 8-9, (pp 67-94) Due Wednesday, April 19, 2006 1. Two intrinsic point defects are a(n) vacancy , a missing atom, and a(n) interstitial , an extra atom of the same material. (2) 2. Rank these three materials classes (metals, ceramics, and polymers) in order of increasing stiffness: (3) Lowest Highest ___polymers __< _____metals _____ < ____________ceramics _______ 3. True or false: (3) i. Point defects produce distortions in the host crystal lattice. True ___ ii. Amorphous materials lack short-range order. False ___ iii. Ceramics are much stronger in tension, than in compression. False ___ 4. In the iron wire demo, the wire experienced a phase ___transformation during heating from ___BCC ___ to ___FCC _____ structure, which made the wire contract slightly even though materials tend to expand during heating. This property of changing structure is known as __polymorphism ___. (4) 5. Young’s modulus is the _stress _ divided by the ___strain __ and it defines the...
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- Spring '10
- Materials Science, cross-sectional area, original length, ultimate tensile stress, Intrinsic point defects, ii. Amorphous materials