VACUUM SINTERING AND OPTICAL PROPERTIES OF Gd_(0.98)LuTb_(0.02)O_3 TRANSPARENT CERAMICS

Nano-scaled Gd_(0.98)LuTb_(0.02)O_3 ceramic powders were prepared by the combustion method.Without the addition of any additives or sintering agents,the powders were molded after appropriate dry-pressing and isostatic-pressing.The effects of the sintering temperature and the sintering time on the densification and the grain growth process of Gd_(0.98)LuTb_(0.02_O_3 ceramics were investigated. Based on the acquired research results,the sintering process was adjusted,and Gd_(0.98)LuTb_(0.02)O)3 transparent optical ceramics were obtained after sintering at 1 750℃for 6 h.The transparent ceramics of Gd_(0.98)LuTb_(0.02)O_3 show a transmittance of over 70% across 0.2 mm and a relative density of 99.8%.The ceramics emitted a strong yellowish green light with the main peak at 540 nm excited by X-ray,corresponding to the ~5D_4→~7F_5 of Tb~(3+) transition.