On Microstructure and Wear Behavior of Microwave Processed Composite Clad

In the present study, wear resistance composite cladding of Ni-based + 20% WC8Co (wt. %) was developed on SS-304 substrate using domestic microwave oven at 2.45 GHz and 900 W. The clad was developed within 300 s of microwave exposure using microwave hybrid heating (MHH) technique. The clad was characterized through scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), Vicker’s microhardness, and dry sliding wear test. Microstructure study revealed that the clad of approximately 1.25 mm thickness was developed by partial mutual diffusion with substrate. It was observed that the developed clad was free from visible interfacial cracks with significantly less porosity (∼1.2%). XRD patterns of the clad confirmed the presence of Cr₂₃C₆, NiSi, and NiCr phases that eventually contributed to the enhancement in clad microhardness. Vicker’s microhardness of the processed clad surface was found to be 840 $±$ 20 HV, which was four times that of SS-304 substrate. In case of clad surface, wear mainly occurs due to debonding of carbide particles from the matrix, while plastic deformation and strong abrasion are responsible for the removal of material from SS-304 substrate.