Wear and high-temperature corrosion behaviorof a wire-arc sprayed NiCrB coating

A new NiCrB cored wire was used to produce protective coatings for components used in high-temperature environment by wire-arc spraying process. The microstructure, wear resistance and high-temperature corrosion behavior of the NiCrB coating were investigated in comparison with a traditional NiCrTi coating. The NiCrB coating presented a homogeneous structure with significantly fewer oxide inclusions, but a slightly higher porosity than the NiCrTi coating. The NiCrB was harder than the NiCrTi coating, thus leading to its superior wear resistance. Thermogravimetric technique was used to evaluate the high-temperature corrosion behavior of the coatings in molten salt environment (Na2SO4 with a mass fraction of 10% NaCl) at 800 °C under cyclic oxidation condition. The results showed that the NiCrB coating exhibited excellent corrosion resistance as the NiCrTi coating.