Effect of sintering temperature on the transparency and mechanical properties of lutetium aluminum garnet fabricated by spark plasma sintering

Abstract: Transparent lutetium aluminum garnet (Lu3Al5O12, LuAG) was fabricated by reactive spark plasma sintering. The effect of sintering temperature on the crystal phase, microstructure, transparency and mechanical properties of LuAG bodies was investigated. Fully dense and single-phase LuAG bodies were obtained at sintering temperatures 1573–1923K. The average grain size increased from 0.18 to 0.52μm with increasing sintering temperature from 1573 to 1773K, and grain growth became significant at 1823K. Transmittance showed a maximum value of 77.8% at 2000nm at a sintering temperature of 1773K after annealing at 1423K in air for 43.2ks. The Vickers hardness increased from 14.2 to 17.2GPa with decreasing grain size from 7.45 to 0.23μm. [Copyright &y& Elsevier]