Yield strength of transparent MgAl 2O 4 nano-ceramic at high pressure and temperature

Abstract

We report here experimental results of yield strength and stress relaxation measurements of transparent MgAl 2O 4 nano-ceramics at high pressure and temperature. During compression at ambient temperature, the differential strain deduced from peak broadening increased significantly with pressure up to 2 GPa, with no clear indication of strain saturation. However, by then, warming the sample above 400°C under 4 GPa, stress relaxation was obviously observed, and all subsequent plastic deformation cycles are characterized again by peak broadening. Our results reveal a remarkable reduction in yield strength as the sintering temperature increases from 400 to 900°C. The low temperature for the onset of stress relaxation has attracted attention regarding the performance of transparent MgAl 2O 4 nano-ceramics as an engineering material. © 2010 The Author(s).