1. Why are steels used so extensively?
2. What is the composition of a 4140 steel?
3. Suggest a reason why rivets made of a 2017 aluminum alloy are refrigerated until they are used.
4. Compare age hardening of aluminum alloys and the quenching and tempering of steel with respect to the processing steps. How do the mechanical properties change during each step for both types of alloys.
5. What is the purpose of annealing an alloy?
6. Determine yield strength, modulus of elasticity, tensile strength, elongation, for data given below.
7. Suppose a metal piece has a dislocation density of 104 /mm2. If all the dislocations in 1 cc of the material were somehow removed and linked end to end, how long would this chain be? If the materials was cold worked so that the dislocation density increased to 1010/mm2, how long would the chain be?
8. Describe these strengthening mechanisms and the role that dislocations play in each:
grain size reduction
strain hardening
solid solution hardening
precipitation or age hardening