摘要
用透射电子显微镜，Ｘ射线衍射仪研究了颗粒增强钢基复合材料ＴｉＣ－５０Ｎｂ不同温度回火后的组织与硬度。结果表明，材料中硬质相ＴｉＣ在整个回火温度范围内的显微硬度基本保持不变，对材料的二次硬化效应无贡献。材料的二次硬化主要由基体组织的变化所引起，回火过程中由基体析出Ｍ＿（２３）Ｃ＿６碳化物及残余奥氏体转变为回火马氏体是产生材料二次硬化的原因。
microstructure of TiC reinforced steel based composite was investigated by means of transmission electron microscope and X-ray diffraction analyzer.The results show that the microhardness of TiC does not change with tempering temperarure,so the secondary harden ing of material is independent on TiC particles. The secondary hardening is dependent on the microstructure of matrix, and the effect of secondary hardening is produed by precipitation of M_(23)C_6and the transformation of retained austen ite in matrix duting tempering process.
关键词
二次硬化
颗粒复合材料
碳化物
secondary hardening, particle composite,earbide
