SILICON CARBIDE WHISKER-REINFORCED CERAMICS WITH LOW RATE OF GRAIN SIZE INCREASE UPON DENSIFICATION

摘要

A highly dense composite of a ceramic material and silicon carbide whiskers with grain sizes in the nano-sized range is formed by mechanical activation of the ceramic material in the form of a nano-sized powder, followed by compressing a mixture of the mechanically activated ceramic material and silicon carbide whiskers into a fused mass while passing an electric current through the mixture, preferably by electric field-assisted sintering. The nano-sized grains in the final microstructure provide the composite with superior mechanical properties, notably strength and toughness.