Grain Growth Mechanism of Tungsten Carbide During Liquid Phase Sintering

초록

A pseudo Monte-Carlo computer model of the formation and growth mechanism of WC grains during liquid phase sintering was constructed on the basis of atomic adsorption and desorption characteristics of crystal planes. The growth rate was higher for{1bar010} and {21bar1bar0} crystal planes and lower for the basal plane. Anisotropic growth rates of various crystal planes resulted in prism-shape grains observed actually in real materials. Abnormal grain growth was attributed to coalescence among the prism-shape grains. It was shown that two grains with their respective(11bar00) and (101bar0) planes meeting at a correct angle could coalesce easily. Coalescence probabilities between various crystal plane pairs were computed using the present model and they were compared with calculated values of an existing theory, and the two were in good agreement.