EFFECT OF COBALT CATALYST ON THE FORMATION OF SIC FROM RICE HUSK SILICA-CARBON BLACK MIXTURE

Cobalt has been found to act as a strong catalyst in increasing the fo rmation of total SiC by decreasing the crystallization of carbon black . The formation of SiC whiskers in the presence of cobalt catalyst is found to be low. No alpha-SiC has formed in the presence of Co catalys t. With Co catalyst needle-like whiskers are formed. Without any catal yst (a) slow heating has decreased the reactivities of carbon black an d rice husk silica by increasing their degree of crystallization and ( b) rapid heating has increased the formation of SiC particulates. With Co catalyst rapid heating has been found to be beneficial in increasi ng the whisker content.