Abstract: Translucent AlN ceramics were prepared by hot pressing with AlN powder synthesized by using carbon thermal reducing method and additive CaC₂. The experiments
show that the AlN powder with high purity, small particle size and narrow size distribution is necessary for translucent AlN ceramics. CaC₂ is an effective sintering
additive for translucent AlN ceramics, improving the densification of AlN and evaporating cleaning the grain boundary. The product is translucent in the range
of ultraviolet to infrared. The microstructure study shows that the translucent reason is the grains of AlN complete growing and closely arranging.

Key words: translucent ceramic，aluminum nitride，preparation