Yield Strength of Transparent MgAl2O4 Nano-Ceramic at High Pressure and Temperature

• Published in: Nanoscale research letters Vol. 5; no. 8; pp. 1329 - 1332
• Main Authors: Zhang, Jie, Lu, Tiecheng, Chang, Xianghui, Jiang, Shengli, Wei, Nian, Qi, Jianqi
• Format: Journal Article
• Language: English
• Published: New York Springer New York 23.05.2010; Springer
• Subjects: Chemistry and Materials Science; Materials Science; Molecular Medicine; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanotechnology; Nanotechnology and Microengineering; High pressure/temperature; Stress relaxation; Differential strain; Yield strength; nano-ceramics; Transparent MgAl; O
• ISSN: 1931-7573; 1556-276X
• DOI: 10.1007/s11671-010-9647-5

We report here experimental results of yield strength and stress relaxation measurements of transparent MgAl 2 O 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 2 O 4 nano-ceramics as an engineering material.