An approach for developing nickel–alumina powder-based metal matrix composite cladding on SS-304 substrate through microwave heating

In the present study, metal matrix composite clads of nickel–alumina powder-based material have been produced on austenitic stainless steel (SS-304) substrate using microwave heating at 2.45 GHz frequency. A concept of hybrid heating was used to process metal matrix composite clads at exposure power level of 900 W. The exposure time for developing metal matrix composite clads was varied from 60 to 300 s. The clads of average thickness 0.6 mm were successfully developed at an optimized exposure time of 300 s. The microstructural analysis of microwave processed clads reveals the uniform dispersion of alumina powder particles inside nickel matrix. The developed clads were free from any type of interfacial cracks and were metallurgically bonded with SS-304 substrate. X-ray diffraction study confirmed the presence of alumina powder, FeNi₃ and chromium carbide phases, which contributed to the increase in micro-hardness of developed clad. Clad micro-hardness was found to be four times that of austenitic stainless steel, which makes it suitable for anti-wear applications.