自由圧縮変形における高純度アルミニウム双結晶の粒界の挙動

Abstract

Grain boundary sliding during a constant rate heating under various constant compressive stresses of 20 kg/cm2 to 35 kg/cm2 were observed in high purity aluminium bicrystals with boundary misorientation angles of 33°37′ and 33°19′. The bicrystal specimens were prepared by the Bridgemann method. Grain boundaries were situated parallel and normal to the compressive direction. The main results obtained were as follows. (1) When grain boundaries were situated parallel to the compressive direction, grain boundary sliding increased with increasing compressive stress up to 25 kg/cm2, but when the stress increased to 30 kg/cm2, the amount of grain boundary sliding became smaller than that for the compressive stress of 25 kg/cm2. In the case of normal compression, grain boundary sliding increased with increasing compressive stress up to 30 kg/cm2. (2) Grain boundary sliding during the free compressive deformation was caused by the misorientation of component crystal for external stress. (3) Grain boundary situated normal to the compressive direction migrated well. (4) The behaviour of the deformation layer in the region adjacent to the grain boundary affected strongly the difference in activation energy for grain boundary sliding by the compressive direction.