Effect of rice husk ash in whiteware compositions

Quartz was progressively replaced by ground active silica obtained from rice husk ash (RHA) in a traditional whiteware composition and the effect of this replacement on the vitrification behaviour and mechanical and thermal properties in relation to the microstructure of specimens has been investigated. It has been found that the complete replacement of quartz by RHA drastically reduced both the maturing temperature and the percentage of thermal expansion, and increased the strength marginally. The improvement in the properties is attributed to sharp changes in the microstructural features as a result of significant reduction in the content of quartz phase and the simultaneous increase in glassy phase.