Hardness degradation in liquid-phase-sintered SiC with prolonged sintering
✍ Scribed by O. Borrero-López; A. Pajares; A.L. Ortiz; F. Guiberteau
- Publisher
- Elsevier Science
- Year
- 2007
- Tongue
- English
- Weight
- 503 KB
- Volume
- 27
- Category
- Article
- ISSN
- 0955-2219
No coin nor oath required. For personal study only.
✦ Synopsis
The effect of the sintering time on the Vickers hardness of liquid-phase-sintered SiC with 10 wt% YAG additives was studied for materials fabricated in Ar and N 2 atmospheres. The hardness of the Ar-sintered materials was found to decrease markedly with increasing sintering time, whereas, in contrast, the decrease was only marginal for the N 2 -sintered materials. Berkovich nanoindentation tests showed that the softening could not be attributed in either case to degradation of the SiC grains, thereby pointing to the intergranular YAG phase as the responsible. That the cause was degradation of the YAG phase was confirmed by X-ray energy-dispersive spectrometry and Hertzian indentation tests. The far more pronounced softening observed for the Ar-sintered materials reflects the more severe degradation that the YAG phase undergoes during sintering in this atmosphere.