烧结助剂对Sialon常压烧结的影响

摘要

The pressureless sintering process adding Y2O3 and Y2O3+La2O3 as sintering aids was studied. It was found that a Sialon ceramic adding 6% Y2O3 as sintering aid was sintered to over 99% TD when sintered at 1750℃ for 1h. Y2O3 can partially be replaced by La2O3, and the best sintering temperature of Y-La-Sialon is a little higher than that of Y-Sialon. The phase structure studies of Y-La-Sialon showed that La can restrain the growth of α′ and YAG phase in Sialon. The effect of chemical mixing is not as good as that of mechanical mixing because of transformation of γ-Al2O3 to α-Al2O3 in the sintering process and other factors.%研究了以Y2O3和Y2O3+La2O3为烧结助剂的Sialon陶瓷的常压烧结过程及其相结构。结果表明：添加6%Y2O3在1750℃常压烧结1h可获得相对密度大于99%的Sialon陶瓷；La2O3可部分或大部分取代Y2O3，混合烧结助剂的最佳烧结温度(1800℃)略高于单纯以Y2O3为烧结助剂的最佳烧结温度(1750℃)。加入La抑制了α′相和YAG相的生成，选择合适的工艺条件，可制得α′+β′复相陶瓷。探讨了用Sol-Gel化学法混料代替机械法混料的可能性，由于γ-Al2O3转变成α-Al2O3等原因，化学混料法的效果不如机械法。