Characterization of erbium oxide doped HP-HVOF deposited carbide ceramic coating on martensitic steel

Abstract

Rare earth elements (REEs) are known as the “vitamin or nutrients” of metals. The addition of rare earth in a limited quantity can enhance the properties of materials. This article elucidates the effect of doping of rare earth oxide (0.9 wt.% Er2O3) on the mechanical and surface behavior of tungsten carbide (WC-10Co-4Cr) based coatings developed using high pressure high velocity oxygen fuel (HP-HVOF) thermal sprayed techniques on martensitic stainless steel (SS410). With the addition of rare earth oxides, the result shows that the hardness of the deposited coating (HV1261.17) is far higher than the substrate (HV193.47). The modulus of elasticity and flexural strength is enhanced for the coated sample as compared to the substrate. The porosity level of the coating is found to be less than 1% and the static water contact angle for coated surface (≈125.1°) shows the coated sample is hydrophobic in nature. The surface characterization was done using the scanning electron microscope attached with energy dispersive X-ray analysis which has identified the presence of various elements on the surface including rare earth. The surface of coated samples has various phases of rare earth oxides such as monoclinic and cubic rare earth oxides. Moreover, its compounds such as Co3W3C were confirmed by X-ray diffraction measurements. After comparing previous literature with current results can conclude that the addition of rare earth oxides (0.9 wt.% Er2O3) on carbide coatings enhanced the various properties of materials.