Effect of Aspect Ratio and Liquid-Phase Content on Densification of Alumina-Silicon Carbide Whisker Composites

Densification of alumina-SiC whisker composites by pressureless sintering is inhibited as a result of whisker interference with particle rearrangement and composite shrinkage. Reduction of the aspect ratio improves densification by improving particle/whisker packing for increased green densities and enhances the ability of the whiskers to rearrange themselves during sintering. Increasing the amount of liquid phases present during sintering also improves densification by aiding whisker rearrangement.