Microstructure and properties of coatings with rare earth formed by DC-plasma jet surface metallurgy

A new method of surface modification, DC-plasma jet surface metallurgy, is proposed in order to improve wear resistance of materials. This paper reports on an experiment, in which some metallurgical coatings of iron-based alloy with different contents of La2O3 and CeO2 were prepared on AISI1020 steel using a homemade DC-plasma jet surface metallurgy equipment. A scanning electron microscope (SEM), energy dispersive X-ray (EDX) microanalysis and X-ray diffraction analysis (XRD) were employed to observe the microstructure and analyzed the chemical compositions of coatings. The effect of RE oxide (La2O3 and CeO2) on microstructure and properties of coatings was investigated. The result shows that addition of a proper amount of RE oxide (La2O3 and CeO2) can refine and purify the microstructure, significantly increase microhardness and enhance the wear resistance.