Surface modification of martenistic stainless steel through microwave hybrid heating

Abstract

Surface modification of martensitic stainless steel through microwave hybrid heating was investigated. The present work mainly focuses on development of hardfaced carbide layer and intermetallic matrix composite (IMC) with reinforcement, and their characterization. The clads were developed using nickel based powder with 10 wt.% silicon carbide (Ni+10%SiC) and nickel aluminium powder with 10 wt.% silicon carbide (Ni-Al+10%SiC). The XRD results of two clad layers confirm phases of high carbide Cr 26 iii C 6 and NiAl– Ni 3 Al intermetallic composites. Characterization of clad surface results that the microstructure of the developed clad Ni+10%SiC has dendritic morphology and in Ni-Al+10%SiC clad shows composite like structure with reinforcement of SiC both in melted and unmelted form confirmed by EDS. The microhardness of Ni+10%SiC and Ni-Al+10%SiC clads were 2.86 and 2.76 times higher than that of substrate material. Also the wear resistance is improved by 71 times and 52 times as compared to substrate. The Ni+10%SiC clad exhibit better wear resistance than both the Ni-Al+10%SiC clad and substrate is due to presence of hardfaced carbide particles also presence of un-melted SiC particles between the mating surface results in ploughing of material and this leads large number of craters formation on the surface of clad. The craters are very sensitive to wear.