The properties and mechanism of transparent glaze enhanced by mullite with trepang-like structure

In this study, mullite crystals were incorporated into the CaO-Al 2 O 3 -SiO 2 based transparent glaze. The effects of particle size on the composition and structure of the glaze were investigated. Moreover, the mechanical and optical properties of the glaze were studied. The results reveal that reducing the mullite particle size leads to a gradual increase in Vickers microhardness and a simultaneous decrease in wear weight loss. The microstructural analysis indicates that smaller mullite particles in the initial materials result in the formation of finer crystals in glaze after firing, thereby enhancing the mechanical properties of the glaze. The concurrent abrasion of mullite crystals and glass contributes to high wear resistance of the glaze. Notably, the transparency of the glaze remains almost unaffected by the mullite addition, due to the close refractive index of mullite to the glaze.