Effects of rare earth oxide additives on the thermal behaviors of aluminum nitride ceramics

The effects of Y₂O₃ and Er₂O₃ on the sintering behaviors, thermal properties and microstructure of AlN ceramics were investigated. The experimental results show that the sintering temperature can be decreased; the relative density and thermal behavior can be improved by adding rare earth oxide in AlN ceramics. For AlN ceramics with 3 wt.% Er₂O₃ additive, the relative density is 98.8%, and the thermal conductivity reaches 106 W·m⁻¹·K⁻¹. The microstructure research found that no obvious aluminum erbium oxide was found in AlN ceramics doped with 3 wt.% Er₂O₃, which favored the improvement of the thermal conductivity of AlN ceramics.