等离子熔覆技术的研究现状及展望

等离子熔覆技术是一种高效且应用广泛的表面处理技术,具有与基体结合良好、设备成本低、工作环境无污染及操作简单等优点。从等离子熔覆工艺参数研究、等离子熔覆合金涂层、等离子熔覆颗粒增强金属基复合涂层、等离子熔覆层质量调控方法、等离子熔覆技术应用等五个方面,介绍了等离子熔覆技术当前的发展概况。其中,关于等离子熔覆工艺参数研究方面,阐述了熔覆电流、离子气体流量、送粉气体流量、粉末送粉量、焊枪摆动幅度、焊接速度、喷嘴与工件之间的高度及多道搭接时搭接率等参数对涂层组织性能的影响;在等离子熔覆合金涂层方面,介绍了等离子熔覆用合金粉末及其引入方式的研究进展;在等离子熔覆颗粒增强金属基复合涂层方面,叙述了增强颗粒及其添加方式的最新研究成果;在等离子熔覆层质量调控方法部分,阐述了预热缓冷、热处理、外加磁场、机械振动、超声波辅助、加入变质剂及添加稀土元素等手段对熔覆层的质量调控作用;在等离子熔覆技术应用方面,介绍了等离子熔覆技术在矿山机械、汽车零部件再制造以及阀门修复等领域的应用。最后对等离子熔覆技术的应用前景及发展趋势做出了展望。

Research and Development Trend of Plasma Cladding Technology

Plasma cladding technology is an efficient and widely used surface treatment technology, which has the advantages of good bonding with the substrate, low equipment cost, no pollution in the working environment and simple operation. The current development of plasma cladding technology was introduced from five aspects: plasma cladding process parameters, plasma cladding alloy coating, particle reinforced metal matrix composite coating by plasma cladding, plasma cladding coating quality control measures of coating, plasma cladding technology application, etc. In terms of the plasma cladding process parameters, the influence of the parameters such as cladding current, ion gas flow rate, powder gas flow rate, powder feeding amount, welding gun swing amplitude, welding speed, height between nozzle and workpiece, and overlap ratio for multiple lapping on the coating microstructure was described. In the aspect of plasma cladding alloy coating, the types of alloy powders for plasma cladding and their introduction methods (pre-coating method and simultaneous powder feeding method) were introduced. In plasma cladding particle reinforced metal matrix composite coatings, the latest research results of reinforcing particles and their addition methods were summarized. In quality control method of plasma cladding coating, the quality control effect of preheating slow cooling, heat treatment, external magnetic field, mechanical vibration, ultrasonic assist, addition of modifier and addition of rare earth elements on the cladding layer was described. In the application of plasma cladding technology, the application of plasma cladding technology in mining machinery, automotive parts remanufacturing and valve repair was introduced. At last, the application prospect and development trend of plasma cladding technology are prospected.