Plastic Deformation of Corundum Single Crystals

Abstract

The stress‐strain curves and the defect structure of corundum single crystals (sapphire and ruby) were studied. The influence of impurity (Cr) presence, crystallographic orientation, temperature, and deformation rate was investigated. Chromium makes corundum harder and causes a yield point phenomenon. The yield point was also increased by the transition from 60° to 90° orientation of the specimens, by lowering the temperature, and by an increase in the deformation rate. In 60°‐specimens the deformation occurs by means of gliding on basal planes in 〈1120〉 and 〈1010〉 directions. In 90°‐samples beside this one gliding in (1010), (1011), (2021) and (2243) is found.