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

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.