研究了Si3N4粉末粒度、相组成、AlN粉末的粒度及分阶段烧结工艺对气压烧结/-sialon的致密化、产物相组成和力学性能影响. 采用三阶段保温烧结(1700C，1h, 1800C，1h及 1950C，1.5h)减少了Si3N4与液相在高温反应促进了材料致密. 适当的烧结工艺下及用适当的埋粉，细AlN原料有利于材料致密. 细Si3N4原料(0.3)中氧杂质增加导致复合材料中-sialon相减少. 实验中采用-Si3N4?原料时，产物中没有发现-sialon. 当Al2O3添加量发生较小变动时(如?从3.7mol%变为5.1mol%)，产物显微形貌发生明显变化. 当以YAG代替等量的Al2O3和Y2O3作为添加剂时，产物中含有更丰富的长柱状-sialon晶粒，13001900C相动力学过程研究表明：YAG延缓-sialon的生成. 较少的-sialon空间限制及较多的液相促进-sialon晶粒的生长.
The effects of sizes and phases contents of the starting materials Si3N4 and AlN, YAG additive and preheating conditions on the gas-pressure sintering behavior, phase compositions and properties of Y-α/β-sialon composites were investigated. Three stages of sintering (1700C for 1h, 1800C for 1h and 1950C for 1.5h) are necessary for the densification of Y-α/β-sialon composites as the reaction between Si3N4 and liquid phases at high temperature is minimized. Fine AlN powder is beneficial for the densification with proper sintering schedule and embedding powder. Amount of -sialon phase in the product is decreased when very fine Si3N4 (0.3) is used because of increased oxygen content in the powder. No -sialon phase was found in the product when pure -Si3N4 was used as raw material in our experiment. By adjusting the Al2O3 amount such as from 3.7mol% to 5.1mol%, the morphologies of the samples varies greatly. The amount of elongated grains increases obviously in the sample with YAG instead of Y2O3 and Al2O3 as additive. Phase development study at the temperatures between 1300C to 1900C shows that YAG additive postpones the formation of -sialon.
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