Manoj Kumar G, Aru Kumar B, Manikandan AR
This paper discusses about a new amorphous coating of FeCrB (composition of 59%Fe-26%B-15%Cr in wt %) that was done on medium carbon steel substrate (AISI 4340), by means of High Velocity Oxy-Fuel (HVOF) thermal spray. A variety of tests were performed to assess the quality of the coating obtained: The microstructure characteristics of powder and coating were investigated using Scanning Electron microscopy (SEM) coupled with Energy Dispersive Spectroscopy (EDS) and optical microscopy. The initial phase contents of powder and coatings were studied by X- ray diffraction (XRD). The microscopy studies showed that the coatings contained unmelted particles; moreover, oxides and micro-cracks were observed at the surface. The mechanical property of the coatings was characterized using micro hardness test. The test results showed that the coating has increased the hardness three times greater than the substrate. The coated surface showed lower level of porosity. All the above results reveal that the coated region shows better surface properties than the substrate