Preparation of γ-AlON Transparent Ceramics by One-step Method with High-Activity Al2O3 Powders

In this paper, gamma-AlON transparent ceramics are fabricated by one-step method-reactived hot-pressuring sintering technology by using as-prepared gamma-Al2O3 powder as raw material. And the sintering process is also improved from two aspects: adjusting sintered technique parameters and improving the sintering agents. XRD, SEM, ICP-AES analysis results show that as-prepared gamma-Al2O3 powders have advantages of super-fine, high-purity and high-activity so that can meet the requirements of starting material. By adding 1wt% Y2O3 as sintering agent, single-phase gamma-AlON transparent ceramic can be fabricated under the optimum technological condition: hot-pressure sintering at 1950 degrees C for 6h, under nitrogen atmosphere. The results from XRD and SEM indicate that the gamma-AlON ceramic has high density and fine microstructures with relative density of 99.22%. The test result of IR spectrum show that the ceramic yield the best transmittance of 18.42% at 2.5 mu m and its transmitting wavelength range extend from 1.5 to 4.5 mu m.