Journal of Inorganic Materials

• Research Paper • Previous Articles     Next Articles

Mechanical Properties and Toughening Mechanism of SiO2-Si3N4 Composite

YAO Junjie; LI Baoshun; HUANG Xiaoxian; GUO Jingkun   

  1. Shanghai Institute of Ceramics; Chinese Academy of Sciences Shanghai 200050 China
  • Received:1996-01-05 Revised:1996-01-29 Published:1997-02-20 Online:1997-02-20

Abstract: SiO2-Si3N4 composites were prepared by hot pressing process. Their flexural strength and fracture toughness obtained are 143MPa and 1.7MPa.m1/2, which are 107% and 70% higherthan those of the SiO2 matrix material respectively. The addition of higher elastic modulus Si3N4 particulates and the residual stress caused by the difference in thermal expansion coefficient of Si3N4 and SiO2 are the main reason responsible for the improvement of mechanical properties of the composites.

Key words: silica, silicon nitride, composite, toughening mechanism