Tribological Properties of B4C-Ni Cermet Coating Produced by HVOF Process on the Surface of 4130 Steel

In this research, B4C-Ni cermet coating was sprayed on the surface of 4130 steel from B4C and Ni feed-stockpowders using high velocity oxy-fuel (HVOF) method. In order to characterize the tribological behavior of thecoating, ball on disk wear tests were done at the ambient temperature and under the loads of 1, 3 and 5 N.Phase analysis of the coating after spraying was studied by X-ray diffractometery (XRD). Microstructure of thecoating and wear track was evaluated by scanning electron microscopy (SEM), field emission scanning electronmicroscopy (FE-SEM) and energy dispersive spectroscopy (EDS). The microhardness test was done to measurethe hardness of the produced coating. It was found that a good coating with suitable interface and no significantpores and cracks in the microstructure of coatings was formed. The main wear mechanism of the coating wasdelamination with some oxide layers due to the frictional heat during wear test.