EFFECT OF TENSILE DIRECTION ON DEFORMATIO N AND RECRYSTALLIZATION IN A COPPER BICRYSTAL

In order to clarify the effect of active slip systems on the recrystal lization along/near the grain boundaries, three kinds of 99.99 mass% c opper bicrystal specimens, which have the same original grain boundary and different tensile directions, were prepared. When they are deform ed in tension to a strain of 0.3, the grain boundary is changed into d ifferent ones because of the operation of different slip systems. Afte r annealing the recrystallization along/near the grain boundary occurs mainly due to [111] rotation mechanism in the bicrystal in which mult iple slips of dislocations with large screw components on a certain sl ip system and those on other ones take place. In contrast, the strain induced grain boundary migration mechanism operates in the bicrystal w hose grain boundary plane is parallel to edge dislocations entered int o and piled-up toward the grain boundary.