基于全自动热喷涂技术的电力设备零部件涂层制备工艺研究

变电设施常常服役于空气环境中,容易受到腐蚀的影响,对设备进行表面改性处理可以大幅改善设施的防腐蚀性能,提升其使用寿命。全自动热喷涂技术作为一种新型表面改性方式,是通过热源将合金加热至熔融或半熔融状态并涂覆与基体表面的技术。本文对其工艺参数进行了系统研究,发现当喷涂速度为0.1m/s,涂层厚度最大(700μm)、孔隙最小(2.1%)、性能最佳。喷涂距离对涂层孔隙率的影响较大,在距离为180mm,孔隙率达到最低(4.3%),此外还可根据对涂层厚度需求以及孔隙率的大小选择合适的喷涂电压和电流。对最佳参数条件下热喷涂铝涂层的试样进行盐雾试验。发现涂层表面会发生氧化腐蚀,生成以Al(OH)₃为主的腐蚀产物并在涂层表面形成致密的氧化膜。此外,产生的腐蚀产物还可以填补热喷涂过程中形成的孔隙,阻止腐蚀介质继续向涂层内部渗入。

Study on coating technology of power equipment parts based on automatic thermal spraying technology

Substation facilities are often used in the air environment and are susceptible to corrosion. Surface modification treatment of equipment can greatly improve the anti-corrosion performance of the facility and prolong its service life. Automatic thermal spraying technology, as a new surface modification method, is a technology that heats the alloy to molten or semi-molten state by heat source and coats the surface of the substrate. In this paper, the process parameters of fully automatic thermal spraying technology are studied, and the spraying process parameters with the best corrosion resistance are found, including spraying speed, maximum coating thickness, minimum porosity, spraying distance, spraying voltage and current. For these optimal parameters, a salt spray test was carried out on the thermal spray aluminum coating. The results show that oxidative corrosion occurs on the coating surface, and a corrosion product dominated by Al(OH)3 is generated and a dense oxide film is formed on the coating surface. In addition, the resulting corrosion products fill the pores created during thermal spraying, preventing the corrosive medium from penetrating further into the coating.