Research on Performance Optimization of Ni60-Inconel625 Cladding Layer Prepared by Additive Manufacturing for Mining Robot Arm

For insufficient wear resistance and corrosion resistance of 45 steel used in underground robot arms, laser cladding additive manufacturing was used to prepare a composite cladding layer of Ni60 and Inconel625 alloy (1:1 mixing ratio) on the surface of 45 steel. The microstructure evolution of the cladding layer and its influence mechanism on mechanical properties, wear resistance, and corrosion resistance were systematically studied through microstructure analysis, microhardness test, friction and wear test, and corrosion resistance test. The results show that the average microhardness of the Ni60-Inconel625 mixed alloy cladding layer is 454.74 HV, which is 2.72 times of that of 45 steel. The wear volume of the cladding layer is 0.115 mm³, which decreases by 0.165 mm³ compared with that of the substrate. The wear rate of the cladding layer is 1.28×10^-2 mm³/(N·m), which decreases by 28.49% compared with that of the substrate, demonstrating good wear resistance. Under the same corrosion environment conditions, the corrosion current density of the Ni60-Inconel625 mixed alloy cladding layer is lower than that of the substrate, and the self corrosion potential and polarization resistance are higher than those of the substrate. The frequency stable region at the highest impedance modulus |Z| is wider than that of the substrate, and the corrosion rate is reduced compared to the substrate, showing good corrosion resistance. The composite cladding layer significantly improves the service performance of the substrate, providing a basis for material optimization of underground robot arms in complex environments.