Preparation and Characterizations of NiCrFeSiAlBC Coatings via a HVOF Process

Thermal spray composite coatings have been widely used in a diversity of industrial applications, particularly, the high-velocity oxy-fuel (HVOF) thermal spraying nickel alloy coatings have been used to enhance the wear resistance of various engineering components especially for the machining tools. In the present work, NiCrFeSiAlBC coating was deposited on C45 substrate with the HVOF thermal spray process and the microstructure, mechanical and tribological properties of the deposit was investigated. The microstructure of the HVOF-sprayed NiCrFeSiAlBC coating was characterized by scanning electron microscope (SEM). The micro hardness was determined in the substrate and in the coating by using Vicker’s micro-indenter, also, tribological tests were conducted via a reciprocating ball on flat tribometer at 10 N normal load, the ball being from Si3N4 material. All the results were discussed in relation to the hardness and wear resistance. It was found that the NiCrFeSiAlBC coating exhibited a very good tribological performance when compared to the uncoated substrate (C45).