(1. 三峡大学 机械与动力学院 水电机械设备设计与维护湖北省重点实验室，宜昌 443002； 2. 常州大学 机械工程学院，常州 213164； 3. 上海交通大学 材料科学与工程学院 上海市激光制造与材料改性重点实验室，上海 200240)
摘 要: 以Fe-Ni-Cr-Ti-C粉末为原料，采用等离子束原位冶金技术在低碳钢表面合成颗粒柱体混杂增强TiC-M7C3/Fe复合涂层。利用光学显微镜、扫描电镜、电子能谱、X射线衍射仪、同步热分析仪及热力学计算，分析TiC与M7C3混杂生长特征，考察干滑动摩擦条件下粒柱混杂结构的摩擦学特性。结果表明：原位合成时初生相TiC可作为次生相M7C3的形核基底促进M7C3形核；TiC-M7C3粒柱混杂与单一M7C3增强相比耐磨性提高了31.5%；其干滑动摩擦温升与滑动距离之间符合指数渐近稳定关系y=a-b×cx；混杂增强时，M7C3磨损面裂纹率和脆性剥落坑增加，涂层的干滑动磨损机理主要为磨粒磨损和氧化磨损。
关键字: 原位冶金；TiC-M7C3；混杂结构；干滑动；摩擦学
（1. Hubei Key Laboratory of Hydroelectric Machinery Design & Maintenance, College of Mechanical and Power Engineering, China Three Gorges University, Yichang 443002, China; 2. School of Mechanical Engineering, Changzhou University, Changzhou 213164, China; 3. Shanghai key Laboratory of Materials Laser Processing and Modification, School of Material Science and Engineering, Shanghai Jiaotong University, Shanghai 200240, China）
Abstract:The TiC-M7C3 hybrid reinforced Fe-based coating was fabricated by in-situ reaction method on low carbon steel plate by plasma in-situ metallurgy process with Fe-Ni-Cr-Ti-C powders. Microstructure and hybrid growth character of TiC-M7C3 in the coating were analyzed by OM, SEM, XRD, EDS, simultaneous DSC-TGA, and thermodynamic analysis. Dry sliding wear behavior of TiC-M7C3/Fe coating was tested and compared with single rod carbide M7C3 reinforced Fe-based coating M7C3/Fe. The results show that the primary phase TiC can effectively act as the substrate for the nucleation of M7C3, thus can promote the formation of M7C3 in the TiC-M7C3/Fe coating. The dry sliding wear resistance, frictional temperature, surface crack rate and brittle peeling pit of M7C3 rod of coating TiC-M7C3/Fe are higher than that of M7C3/Fe. The relationship between temperature and sliding distance fits the exponential asymptotic stability model y=a-b×cx. The main dry sliding wear mechanism of coating TiC-M7C3/Fe are abrasive wear and oxidation wear.
Key words: in-situ metallurgy process; TiC-M7C3; hybrid structure; dry sliding; tribology
