TiC,Co 及添加剂对 Si_3N_4陶瓷显微结构和力学性能的影响

EFFECT OF TiC,Co AND ADDITIVES ON MICROSTRUCTURE AND MECHANICAL PROPERTIES OF Si_3N_4 CERAMICS

用扫描电镜、透射电镜和 X 射线衍射研究了 Si_3N_4-TiC-Co 系复合材料的相组成、显微结构和力学性能。发现 TiC 以 TiC 和 TiN 形式存在,Co 以 CoSi 形式存在。加入 TiC 和 Co 后,复合材料的力学性能得到明显改善,断裂韧性达到7.2MPa·m^(1/m),并且用 Y_2O_3作为助烧剂时,Si_3N_4晶粒成纤维状。

Phase composition,microstucture and mechanical properties ofSi_3 N_4-TiC-Co ceramic composites were investigated by SEM,TEM and XRD.It was found that TiC exists in the form of TiC and TiN whereas Co in theform CoSi.Mechanical properties were improvcd by the addition of TiC andlike structure of S_3N_4 was obtained when using Y_2O_3 as sintering additives.