Yield Strength of Transparent MgAl2O4 Nano-Ceramic at High Pressure and Temperature
1 Department of Physics and Key Laboratory for Radiation Physics and Technology of Ministry of Education, Sichuan University, 610064, Chengdu, People’s Republic of China
2 International Center for Material Physics, Chinese Academy of Sciences, 110015, Shenyang, People’s Republic of China
Nanoscale Research Letters 2010, 5:1329-1332 doi:10.1007/s11671-010-9647-5Published: 23 May 2010
We report here experimental results of yield strength and stress relaxation measurements of transparent MgAl2O4 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 MgAl2O4 nano-ceramics as an engineering material.