预烧结升温速率与HIP 保温时间对AlON 透明陶瓷透光率影响的研究

Alumina nitride(AlON)transparent ceramics are widely used in transparent armor, multimode visible-infrared guidance hoods, and laser windows due to their excellent properties such as high optical transmittance, high mechanical properties, and high chemical stability. The light transmittance of AlON transparent ceramics is closely related to their sintering process. Based on this, this work investigated the effects of pre sintering heating rate and hot isostatic pressing (HIP)holding time on the visible light transmittance of AlON transparent ceramics, and analyzed the phase changes and crystal morphology changes of AlON within the sintering temperature range of 1 300 ℃ to 1 940 ℃, as well as the micro morphology changes of ceramics after HIP. The results show that in the range of 1 400 ℃ to 1 700 ℃, increasing the heating rate helps to reduce the degree of phase decomposition of AlON and improve its optical transmittance. The prolongation of hot isostatic pressing (HIP)post treatment time is helpful to remove residual pores from the interior of AlON transparent ceramics, further improving their light transmittance. AlON transparent ceramics can be highly densified after presintering at 1 940 ℃ for 8 hours without pressure at a heating rate of 10 ℃ / min, and then subjected to hot isostatic pressing at 1 900 ℃ and 190 MPa for 2. 5 hours. Its optical transmittance can be increased to over 80%. Therefore, increasing the pre sintering heating rate and prolonging the hot isostatic pressing holding time reduces the light scattering degree of AlON ceramic decomposition products and pores, which can improve its visible light transmittance.