Investigation of Hardness and Elastic Constants on Silicon Nitride Based Composites by Recording Micro Hardness Tester

摘要

The hardness and the elastic constants on silicon carbide whisker reinforced silicon nitride were measured using recording micro hardness tester. Test force in the range from 20 to 500 mN were applied for the test. Three kinds of samples, silicon nitride containing 0, 10 and 20vol% silicon carbide whiskers were evaluated. In the conventional hardness tests, hardness of the samples increases with whisker content. In the recording hardness test, it was shown that the increase of the hardness was caused by the evolution of the property of the silicon nitride matrix. Addition of silicon carbide whiskers did not affect the hardening of the materials directly, but forbid the grain growth of the silicon nitride, and it made the composites harder with the whisker content