To address the problems of rapid wear, cutting edge passivation and insufficient service life of 65Mn rotary blades during field operation.Methods: Fe/Ni-WC composite wear-resistant coatings were fabricated on the surface of 65Mn steel substrate by plasma cladding technology. Three types of coatings were prepared with three different powder ratios by adding Ni-WC powder into Fe5 alloy powder as the base material. The microstructure, phase composition, hardness distribution and wear resistance of different coatings were systematically investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), microhardness test, wet sand rubber wheel abrasion test and field operation test. Results: The three cladding layers have favorable overall forming quality without obvious macroscopic defects such as cracks and large-sized pores, and all form a continuous and dense metallurgical bond with the 65Mn substrate. The maximum hardness of the coatings ranges from 850 to 1100 HV₀.₅, which is about 2.5 to 3 times that of the 65Mn substrate. The results of wet sand rubber wheel abrasion test show that the wear mass loss of the optimal coating is reduced by 79.03% compared with the 65Mn sample. After 800 mu of cumulative operation, the cumulative wear mass loss of the rotary blade with coating c is 40.2% lower than that of the original blade, with its relative wear resistance reaching 1.67 times that of the original blade; meanwhile, the cutting edge contour is well maintained without large-area coating spalling.

plasma cladding; composite coating; 65Mn steel; rotary blade; wear resistance; field test