Microstructural investigation of Ni based cladding developed on austenitic SS-304 through microwave irradiation

The stainless steel SS-304 is used to produce turbine blades in some of the hydraulic power plants. It has excellent corrosion resistance and forming characteristics. In the present investigation, the nickel based clads were developed through microwave energy using domestic microwave oven equipped with 900 W power at 2.45 GHz frequency. The developed clads were characterized through optical metallography, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD) and porosity. Microstructure study revealed that microwave clads are free from visible interfacial cracks and porosity is significantly less at approximately 0.87%. The various complex metal carbides and intermetallics were found through XRD analysis. The distribution of metal carbides and intermetallics are the clearest indication for the improvement of hardness. The average microhardness of the developed clad surface is 364 ± 70 HV.