Problem 1 A pure screw dislocation in an FCC crystal will tend to dissociate into two partial dislocations. To cross- slip, these partials must recombine. Determine the total work needed to recombine the two partials. To answer this problem, assume both an equilibrium separation distance that is based on the crystal's stacking fault energy and a minimum separation distance that is equal to the Burgers vector of a full dislocation. When calculating the work for recombination, consider the edge and screw components of the partials and the stacking fault that lies between them. How does the total work vary with the stacking fault energy? Let G = 60 GPA, bperfect = 2 10-0 m, v= 0.33, and let y vary from 0.01 to 0.2 J/m.