Preparation of YAG glass-ceramic by combustion synthesis under high gravity

YAG glass-ceramic with a designed composition of 24Y2O3∙40Al2O3∙36SiO2 was prepared by a method which combines combustion synthesis with centrifugation. High temperature glass melt was produced from a highly-exothermic combustion reaction in Al/CuO system. Centrifugation induced high gravity field facilitates the crystallization of YAG from the glass melt. The effects of high gravity field on phase formation, composition distribution and morphology evolution of prepared YAG glass-ceramic were investigated. Morphology of YAG crystals changed gradually from dendritic to polygonal, and finally to columnar shape along high gravity direction. The density increased from 3.49 to 4.12 g cm−3, and the hardness increased from 7.8 to 9.7 GPa along high gravity direction.