Preparation of Mullite Ceramics from Kaolin and Aluminous Materials (Part 1)

Effects of Grain Size and Grinding of Raw Materials

Abstract

In order to obtain corundum-free mullite ceramics from mixtures of kaolin and aluminous materials, effects of grinding of kaolin, particle size of alumina, and particles size, calcination and grinding of aluminum hydroxide on mullitization and densification were investigated. Grinding of kaolin, use of fine alumina and aluminum hydroxide, and calcination and grinding of aluminum hydroxide promoted the mullitization and densification. Firing these mixtures at temperatures higher than 1500°C yielded corundum-free, comparatively high strength mullite ceramics.