Study on the Technique and Properties of Fe-Based Wear-Resistant Coatings via Laser Cladding on Hydraulic Support Inner Walls

To improve the wear resistance of the inner wall of hydraulic support columns, Fe-based coatings X1, X2 and X3 were prepared on the inner wall of a hydraulic support column using laser cladding technology with three different Ni-content Fe-based alloy powders. The microstructure, mechanical properties and tribological performance of these coatings were analyzed using metallographic microscope, 3D confocal surface topography instrument, universal testing machine and high-speed reciprocating friction and wear testing machine. Results showed that three coatings were homogeneous and compact, and had good metallurgical bonding with the substrate. The cladding layers were mainly composed of α-Fe with a BCC structure and a(Fe-Cr) solid solution, with the formation of a(Fe-Cr-Ni) phase in the X2 and X3 cladding layers. Among the three coatings, the tensile strengthes of X1, X2 and X3 were 563, 597 and 470 MPa, respectively, with X2 having the highest tensile strength. The wear rates of the three coatings were all lower than that of the substrate, with the wear rate of the substrate being approximately eight times that of the X2 coating. The wear mechanism of the substrate was primarily dominated by adhesive wear and abrasive wear, while the wear mechanism of the coatings was mainly abrasive wear.