Fabrication of highly-doped Nd3+:YAG transparent ceramics by reactive SPS

4 at% Nd3+:YAG transparent ceramics have been prepared by reactive spark plasma sintering (SPS) in the 1200-1500 degrees C temperature range. Microstructure, phase composition, optical and physico-mechanical properties of the obtained samples have been studied. Rapid heating of oxide powder system under pressure has been shown to provide single-phase garnet ceramics at 1350-1500 degrees C in 5 min. Accelerated kinetics of YAM -> YAP -> YAG phase transformations under SPS conditions make sintering faster by an order of magnitude as compared to conventional routes. 4 at% Nd3+:YAG ceramics obtained at 1350 degrees C under 30 MPa pressure in 5 min possesses mean grain size of 520 nm, microhardness of 13.7 GPa, and in-line optical transmittance coefficient of 70% in the visible wavelength range (for sample thickness of 1 mm).