1. On which {110} planes of BCC iron can a dislocation with a Burgers vector (a/2)[11-1] move?.
2. Strain hardening is often described by a Taylor (or Kocks-Mecking) equation where the stress is proportional to the square root of the dislocation density. If an aluminum alloy had a strength of 120 MPa and a dislocation density of 1012 m-2, what would the strength be after an additional 10 percent plastic strain assuming that dr/de is linear and equal to 6x1014 m-2?
3. the grains near a bullet hole in a sheet of tin. Explain why the grain size increases with distance from the hole and then suddenly decreases.
4. (Calculate the critical diameter for a steel containing 0.40% C, 0.20% Si, 0.60% Mn, 0.80% Cr, and 0.15% Mo with an ASTM grain size of 8 quenched in mildly agitated oil (H=0.3).
5. How thick of a plate of 4140 steel could be hardened to 50% martensite at the center if it were quenched in agitated oil (H=0.35)?