Slip Systems and Their Critical Shear Stress in 3% Silicon Iron

Abstract

Single crystals of 3% silicon iron with controlled orientation were deformed in tension between 20°C and -196°C at various strain-rates. The orientation was systematically selected so that the maximum shear stress was in direction on low index planes. The operative slip systems were examined by surface observation and analysis of yield stress. The result showed the existence of {112} system as well as {110} system. The temperature dependence of critical shear stress of the two systems was separately determined and that of {112} system was stronger than that of {110} system. The critical shear stress for slip is different by 5% between two opposite directions on {112} plane. The strain-rate dependence of critical shear stress was also examined and found to be derived from the stress dependence of dislocation velocity.