Preparation of Neodymium-Doped Yttrium Aluminum Garnet Transparent Ceramics by Homogeneous Precipitation Method

摘要

Neodymium doped-yttrium aluminum garnet (Nd: YAG) transparent polycrystalline ceramics already become substitutes of single crystals because they are provided with easy fabrication, low cost, large size, highly doped concentration, high heat conductivity, mass fabrication, multi-layers and multi-functions. The Nd : YAG precursor powders with loosely dispersed, slightly agglomerated, super fine and YAG cubic crystal phase were synthesized at 1100 deg C by the homogeneous precipitation method, using Nd_2O_3, Y_2O_3, Al(NO_3)_3 9H_2O and urea as raw materials, (NH)_4SO_4as electrical stabilizer, TEOS as sintering additive. The Nd: YAG transparent ceramics were prepared after being vacuum sintered at 1700 deg C for 5 h. The Nd = YAG ceramic materials were characterized by the TG-DTA, XRD, FT-IR, TEM, FEG-ESEM and FT-PL. The results show that the crystallization temperature of YAG is 850 deg C and the intermediate crystal phase YAP forming during the heat treatment transforms to YAG cubic crystal phase at 1050 t. The lasing wavelength of (Nd_(0.01) Y_(0.99))_3Al_5O_(12) transparent ceramics is 1.065 mu m and there exists a slight red-shift compared to the single crystal with the same chemical composition. The optical transmittance is 45 percent in the visible light and 58 percent in the near infrared light and the optical transmittance descends with the decreasing the wavelength.