Abstract

Particulate ceramic composites that were composed of a combustion‐synthesized β′;‐SiAlON matrix and dispersed MoSi2 particles were hot pressed at 1600°C in a nitrogen atmosphere. The physical and mechanical properties of the composites that contained 15, 30, and 45 vol% MoSi2 were evaluated. The average four‐point bend strength, fracture toughness, and Vickers hardness of the composites were in the ranges of 500‐600 MPa, 3‐4 MP·am1/2, and 11‐13 GPa, respectively. The measured mechanical strength and hardness were very similar to the values that were predicted from the rule of mixtures. The fracture toughness of the combustion‐synthesized β′;‐SiAlON (2.5 MPa·m1/2) was apparently enhanced by the MoSi2 particles that were added. The increase in the fracture toughness was predominately attributed to the residual thermal stress that was induced by the thermal expansion mismatch between the MoSi2 particles and the β′;‐SiAlON matrix. The composites showed improved electrical conductivity and oxidation resistance over monolithic β′;‐SiAlON. High‐resolution transmission electron microscopy examination of the composites indicated that the MoSi2 was chemically well compatible with the β′;‐SiAlON.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.