论文部分内容阅读
以La2O3和Y2O3作为复合烧结助剂,采用热压烧结法制备了Si3N4基复合陶瓷材料。研究了保温时间和烧结助剂含量对复合材料微观结构及力学性能的影响。研究表明:所制备的Si3N4/TiC陶瓷复合材料的微观结构呈现纵横交错、相互嵌套的结构,晶粒尺寸呈现明显的双峰分布特征,单位面积内晶粒数量与烧结助剂含量之间呈线性降低关系。当烧结助剂质量含量为8%时,该复合陶瓷材料具有最优的力学性能,其抗弯强度、断裂韧性和Vickers硬度分别达到943MPa,8.38MPa·m1/2和16.67GPa。
Using La2O3 and Y2O3 as composite sintering aids, Si3N4-based composite ceramic materials were prepared by hot-pressing sintering. The effects of holding time and sintering aid content on the microstructure and mechanical properties of the composites were investigated. The results show that the microstructure of the prepared Si3N4 / TiC ceramic composites is in a crisscross pattern and a nested structure, and the grain size of the Si3N4 / TiC ceramic composite exhibits a bimodal distribution. The number of crystal grains per unit area and the content of sintering aids Linearly reduce the relationship. When the content of sintering aid is 8%, the composite ceramic material has the best mechanical properties, and the flexural strength, fracture toughness and Vickers hardness reach 943MPa, 8.38MPa · m1 / 2 and 16.67GPa respectively.