Synthesis of MgO powders by precipitant for transparent ceramics

Abstract

In this experiment, MgO powder was prepared through co-precipitation using NH3·H2O and NH4HCO3 as precipitant. The study aimed to investigate the effects of precipitant content and type on the yield of MgO powders. It was found that the highest MgO yield was obtained using a mixture of NH4HCO3 and NH3·H2O as the precipitant. Furthermore, NH3·H2O as the sole precipitant resulted in the smallest particle size. However, an increase in the precipitant content led to a decrease in the specific surface area of the powders and caused powder agglomeration. Subsequently, MgO transparent ceramics were fabricated using a hybrid sintering method involving hot pressing followed by a subsequent hot isostatic pressing treatment. The best microstructure and the highest infrared transmittance of 81% at 5.81 μm were achieved for the MgO transparent ceramic samples hot-pressed at 1500 °C and then subjected to hot isostatic pressing at 1500 °C. The relative density reached 99.97%.