Microstructure and fretting wear resistance of γ/TiC composite coating in situ fabricated by plasma transferred arc cladding

A γ-(Fe,Ni)/TiC composite coating was in-situ fabricated on plain carbon steel by plasma transferred arc (PTA) cladding using Ni, Ti and graphite alloy powders blend as the precursor material. Microstructure of the coating was examined by X-ray diffraction (XRD), scanning electron microscope (SEM) and X-ray energy dispersive spectrometer (EDS). Microhardness along the depth direction of the coating was measured using a Vickers hardness tester. Room temperature fretting wear resistance of the coating was tested. Results showed that the PTA clad γ-(Fe,Ni)/TiC composite coating had unique spheroidal, vermicular and agglomerated TiC particles, and it had high and almost uniform hardness distribution along the depth direction of the coating. Under fretting wear conditions at ambient temperature, the PTA clad γ-(Fe,Ni)/TiC composite coating exhibited excellent abrasive and adhesive wear resistance.