Powder mixtures with nominal compositions of 75 mol% SiC and 25 mol% AlN as well as 50 mol% SiC and 50 mol% AlN were prepared by ball milling for 1-300 h and subsequently sintered to full density by hot isostatic pressing (HIPing) at 1850°C under a pressure of 200 MPa. Microstructures and properties of the HIP-sintered SiC-AlN powder mixtures were investigated with special attention to the effect of ball milling on the formation of SiC-AlN solid solutions. Extensive ball milling facilitated effectively the formation of solid solutions by improvement in mixing homogeneity and pulverization of the SiC and AlN powders. Thermal conductivity of the HIP-sintered SiC-AlN powder mixtures decreased remarkably with ball-milling time, mainly because of the enhanced formation of solid solutions. Mechanical properties - such as strength, fracture toughness, and microhardness - were dependent on the microstructural homogeneity and the grain refinement resulting from the formation of solid solutions.
|Number of pages||8|
|Journal||Journal of the American Ceramic Society|
|Publication status||Published - 1998 Jun 1|
ASJC Scopus subject areas
- Ceramics and Composites
- Materials Chemistry