Mierostructure and erosion behavior of thermal sprayed FeCrAi/WC composite coating at elevated temperature

A powder cored wire for FeCrAI/WC composite coating by high velocity arc spray technique was developed.The coating composition,microstructurc and phases were investigated by energy dispersive X-ray spectra,X-ray diffraction and scanning electron microscope.The erosion properties of FeCrA1/WC coating were examined with a self-devel-oped erosion test rig at elevated temperature.The FeCrA1/WC coating exhibits the lamellar characteristic of hard particles reinforced composite material.Erosion-corrosion resistance of FeCrA1/WC coating at elevated temperature is higher than that of 20 g steel.Under oblique impact condition,the relative erosion-corrosion resistance of FeCrA1/WC is 1.94~2.89 times higher than that of 20 g steel at temperature of 650 C.It is found that the FeCrA1/WC coating exhibits typical erosion behavior of ductile materials below 450 C.It seems that test temperatures under incidence angle of 90 and the incidence angles of ere dent at the temperature of 650 C have little effect on the solid particle erosion behavior of Fe-CrA1/WC coating.The erosion-corrosion mechanisms of FeCrAI/WC coatings under elevated temperature were discussed.