Nd:YAG ceramics with CaF2 and tetraethoxysilane (TEOS) as sintering additives were fabricated by vacuum sintering at 1750°C for 5 h and the microstructures were characterised using X-ray diffraction and scanning electron microscopy. Scanning electron microscopy result shows that the sintered bulk doped with TEOS contains many pores in the grains. The bulk doped with CaF2 displays uniform microstructure. The average size of the grains is 10 mm and few pores can be detected in this sintered bulk. The maximum transmittance of the sintered Nd:YAG ceramics were 44% doped with CaF2 and 14% doped with TEOS.
