Preparation of Fine-Grained Y2.5Nd0.5Al5O12 + MgO composite ceramics for Inert Matrix Fuels by Spark Plasma Sintering

Abstract

We have studied the feasibility of preparing high-density (98.6–99.5%) Y_2.5Nd_0.5Al₅O₁₂ (YAG)–xMgO (x = 5, 10, 20 vol %) composite ceramics by spark plasma sintering. YAG–MgO powder materials have been prepared via MgO precipitation from an aqueous solution of magnesium nitrate, Mg(NO₃)₂, on the surface of garnet particles. The sintering rate of the YAG–MgO composites has been shown to be controlled by volume diffusion at low temperatures and by grain-boundary diffusion at elevated temperatures.