Gd2O3对O’-Sialon/Si3N4复相陶瓷结构与性能的影响  

Effect of Gd2O3 on Microstructure and Properties of O’-Sialon/Si3N4 Composite Ceramics

作　　者：徐晓虹 米凯峰 吴建锋 周炀 金昊 朱光意 XU Xiaohong;MI Kaifeng;WU Jianfeng;ZHOU Yang;JIN Hao;ZHU Guangyi(State Key Laboratory of Silicate Materials for Architectures, Wuhan University of Technology, Wuhan University of Technology,Wuhan 430070, China)

机构地区：[1]武汉理工大学硅酸盐建筑材料国家重点实验室

出　　处：《硅酸盐学报》2019年第6期803-809,共7页Journal of The Chinese Ceramic Society

基　　金：国家“973”计划(2010CB227105)

摘　　要：以α-Si3N4粉和黑刚玉为原料、Gd2O3为烧结助剂,采用无压烧结工艺制备了O’-Sialon/Si3N4复相陶瓷材料,研究了Gd2O3添加量和烧结温度对样品性能、相组成和显微结构的影响,探讨了Gd2O3对复相陶瓷的作用机理。结果表明:复相陶瓷主晶相为α-Si3N4、β-Si3N4和O’-Sialon,添加Gd2O3一方面可在高温烧结过程中形成液相,促进α-Si3N4的"溶解–析出"过程,有利于α-Si3N4向β-Si3N4的晶型转变以及β-Si3N4晶粒的生长;另一方面可促进α-Si3N4与Al2O3和Si O2的固溶反应,生成O’-Sialon相,使样品中O’-Sialon含量增加。当Gd2O3添加量为6%(质量分数)时,经1 600℃烧结的样品SN-G6性能最佳:气孔率为23.29%;体积密度为2.31 g·cm^–3;抗折强度达到105.57 MPa。O’-Sialon/Si3N4 composite ceramics were preparated by a pressureless sintering method usingα-Si3N4 and black corundum as starting materials,and Gd2O3 as a sintering additive.Effects of Gd2O3 content and sintering temperature on the physical properties,phase composition and microstructure of samples were investigated.The results reveal that the main phase compositions of sintered samples areα-Si3N4,β-Si3N4 and O’-Sialon.Adding Gd2O3 can promote the formation of liquid phase during sintering,favoring the phase transformation ofα-Si3N4 toβ-Si3N4 and the growth ofβ-Si3N4 grains,as well as promotingα-Si3N4 for solid solution reaction with SiO2 and Al2O3 to generate O’-Sialon and increasing the content of O’-Sialon in the sample.Sample SN–G6(Si3N4:80%,black corundum:20%,Gd2O3 addition:6%)sintered at 1 600℃has the optimum performance(i.e.,apparent porosity of 23.29%,bulk density of 2.31 g·cm^–3 and bending strength of 105.57 MPa).

关 键 词：氮化硅 黑刚玉 氧化钆 塞隆/氮化硅复相陶瓷 显微结构 

分 类 号：TQ174.75[化学工程—陶瓷工业]