Determine the stress to cause yielding using Von Mises criteria for the system sx=20MPa,sy=10MPa, and txy=3MPa. Use the following two different approaches.Use the Von Mises criteria directly. syield (in MPa):
The lattice for calcium is FCC, and the radius, r, of a calcium atom is 197pm. Assuming that the dislocation density ? is 5×108cm-2 and that it remains constant, and the plastic shear strain rate ?? is 8×10-5s-1. what is the mean velocity of the dislocation? Note that for an FCC crystal, the Burgers vector is equal to 2r.