The Study on the Property and the Microstructure of Pressureless Sintered h-BN Ceramics

Hexagonal boron nitride ceramic（h-BN）has been prepared by pressureless sintering method. The effect of sintering aids, moulding pressure and sintering temperature on the mechanical properties and microstructures of h-BN were investigated. The results show that the densification of as-prepared h-BN ceramic can be contributed to the addition of sintering-aids and the formation of card-house structure. Because of the high densification and card-house microstructure, the obtained h-BN demonstrates higher bending strength and lower porosity when the moulding pressure is 200MPa, sintering temperature is 1850°C and the contents of sintering aids is 10wt%.