Effect of Y2O3 and La2O3 on the sinterability of γ-AlON transparent ceramics

The paper reports the use of Y2O3 and La2O3 co-doping as a composite sintering additive for the fabrication of γ-AlON transparent ceramics by pressureless sintering. The Y3+ enhanced the mobility of grain boundary and accelerated the grain growth, whereas the La3+ has the opposite effect on grain growth. The sintering additives could cause the formation of liquid phase during sintering, which would greatly promote the densification and eliminate pores. High transparent AlON ceramics with the in-line transmittance of 80.3% at 400 nm wavelength have been prepared when the concentration of sintering additives was 0.12 wt% Y2O3 and 0.09 wt% La2O3.