【摘要】 以碳热还原法合成的 AlN 粉末和市售 BN 粉末为原料,添加 5%Y2O3 为烧结助剂,利用无压烧结制备 AlN-15BN复合陶瓷,研究了烧结温度对 AlN-15BN 复合陶瓷相变、致密度、微观结构以及性能的影响,结果表明:Y2O3 可与 AlN粉末表面的 Al2O3 发生反应生成液相促进烧结,随着烧结温度的升高,复合陶瓷的致密度、热导率和硬度逐渐增加,片状的 BN 形成的卡片房式结构会阻碍复合陶瓷的收缩和致密。在 1 850℃烧结 3 h,可以制备出相对密度为 86.4%,热导率为104.6 W?m-1?K-1,硬度为 HRA56.2的 AlN-15BN复合陶瓷。研究表明,通过添加加工性能良好的 BN制备可加 AIN-BN复合陶瓷,是解决 AIB 陶瓷复杂形状成形问题的一个重要途径。更多还原

【Abstract】 AlN-15BN composite ceramics were produced via pressureless sintering process with BN powders bought from market and AlN powders synthesized by carbothermal reduction method as starting materials, and Y2O3 as sintering aids. The effects of sintering temperature on the phases, density, microstructure of AlN-BN ceramics were studied. The results showed that Y2O3 reacted with Al2O3 presenting on the surfaces of AlN particles and formed liquid phases to promote the densification. The density, thermal conductivity and hardness increased with the increas of sintering temperature, and the plate-like BN crystalline could form a card-house structure which hampers the densification of composite ceramics. AlN-BN composite ceramics with thermal conductivity 104.2 W?m-1?K-1, relative density 86.4% and HRA hardness 562 MPa were produced after being sintering at 1 850 for 3 h.更多还原