Unformatted text preview: Introduction To Materials Science, Chapter 1, Introduction Composites Thin crystalline platelets grown fromCr,lut-on ,- Mo ihs voldhis crystal structure so !i Fe cha na f e t back and forth: chain-folded model Spring 2007 Engineering Material Polyethylene
Polymer composite materials: reinforcing glass fibers in a polymer matrix. University of Virginia, Dept. of Materials Science and Engineering Homework #4
18 The a erag chain leng h is mu (for Wednesday, v30 eMarch, t2007)ch thickness of the crystallite greater than the University of Virginia, Dept. of Materials Science and Engiineeriing of Virgi24ia, Dept. of Materials Science and Engineering U n v e r s ty n 9 Reading Assignments
Chapters 6 Problems
1. Accepting Ludwik equation for plastic deformation
n σ T = KεT prove that the ultimate tensile strength can be expressed as σT = Kn n en ( ‘e’ is the exponential constant) [20 points] 2. A brass alloy is measured to deform to 0.15 true strain at a true stress of 210 MPa and to 0.25 true strain at a true stress of 280 MPa prior to necking. Given that the true stress, true strain relation can be expressed by the Ludwik equation:
n σ T = KεT Predict the true stress necessary to produce a true strain of 0.20 b. Estimate the ultimate tensile strength c. Estimate the engineering and true strains at necking d. Construct the true and engineering stress strain curves [30 points] 3. Problem 6.19 in book [15 points] 4. Problem 6.23 in book [15 points] 5. Problem 6.30 in book [20 points] ...
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This note was uploaded on 02/07/2011 for the course MECH 340 taught by Professor Marwandarwiche during the Summer '07 term at American University of Beirut.
- Summer '07