大模数齿轮表面缺陷Ni基合金等离子熔覆修复技术研究

Study on Plasma Cladding Repair Technology of Ni-based Alloy for Large Modulus Gear Surface Defects

摘要: 针对三峡升船机主驱动齿轮表面点蚀等缺陷，采用三种填充材料Ni20、Ni35、Ni60合金粉末进行等离子熔覆修复试验，研究了熔覆层的组织性能。结果表明：采用Ni60粉末作为填充材料，离子气流量3 L/min、氩气流量9 L/min，熔覆电流135 A、预热温度300℃时，获得的熔覆层具有最好的综合性能，熔覆层组织细密，枝晶晶粒较小，其截面硬度比基材的提高42.3%，磨损量比基材的小74%。

Abstract: For pitting corrosion on the surface of main drive gear of the Three Gorges shiplift, plasma cladding repair tests were carried out by using three cladding filling materials of Ni20, Ni35, and Ni60 alloy powders. The microstructure and properties of the cladding layers were studied.The results show that when Ni60 powder is used as the filling material, the ion gas flow rate is 3 L/min, the argon gas flow rate is 9 L/min, the cladding current is 135 A, and the preheating temperature is 300℃, the cladding layer has the best comprehensive performance. The microstructure of the cladding layer is compact and the grain size of the dendrites is small, and the cross-sectional hardness of the cladding layer is 42.3%higher than that of the base material, and the wear amount is 74%less than that of the base material.