Fabrication of transparent yttrium aluminum garnet ceramic

In this paper, the synthesis of Nd-doped yttrium aluminum garnet (Nd:YAG) spherical nano-crystallites was investigated by using the solvothermal method, and the optimum processing conditions for processing the transparent ceramic preparation was determined. Powder consisting of nanosized particles obtained by the solvothermal method displays significantly less crystallite agglomeration, indicating a high degree of sinterability. The phase structure and the morphology of the YAG crystallites were depended on the reaction conditions, the optimum temperature is 300 centigrade for 1h, at which the pure phase of spherically shaped YAG nanoparticles can be obtained. Microstructure evolution at different sintering stages demonstrated that fully transparent YAG ceramic can be fabricated by vacuum sintering at 1750 centigrade for 5h by using the as-synthesized powders. The ceramic has a relative density of about 99.98% of the theoretical value, and an average grain size of about 3-5μm. The transmittance of the ceramic is 55% in the visible range, and 70% in the infrared range.