What is the hardening exponential n and deformation rate sensitivity exponential m ? Comment similar or different aspects, their numerical values should be big or small and changes with temperature

Example: Consider a metal whose strain hardening behavior follows: 25,000 0.25 psi. If an annealed bar of this metal is pulled in a tension test from a starting dia. of 12.7mm to a dia. of 11.5mm (uniform elongation, no friction, no distortion), what is the work per unit volume required? If the bar is reduced by extruding and the deformation efficiency is 70%, what is the extrusion pressure?

10 - Prob 7. Steady - state creep data taken for stainless steel at a stress level of 70 MPa (10,000 psi) are given as follows: (8 marks) If it is known that the value of the stress exponent n for this alloy is 7.0, compute the steady - state creep rate at 1250 K and a stress level of 50 Mpa. é, (s-1) T (K) 1.0 X 10-5 2.5 X 10-3 977 1089

8.15 List four major differences between defor- mation by twinning and deformation by slip relative to mechanism. conditions of occur- rence, and final result. 8.17 Briefly explain why HCP metals are typically more brittle than FCC and BCC metals. 8.5  a) Define a slip system. ) Do all Do all metals have the same slip system? Why or why not? " 8.42 Briefly explain how each of the following influences the tensile modulus of a semicrys- talline polymer and why: (a) molecular weight; (b) degree of crystallinity; (c) deformation by drawing: (d) annealing of an undeformed material; (e) annealing of a drawn material.