Effect of Y2O3 addition on the organization and tribological properties of Ni60A/Cr3C2 composite coatings obtained by laser-cladding

Abstract

This study aims to enhance the surface toughness and overall performance of arc-shaped nail teeth, which are vital components of presowing film-recovery machinery. Laser cladding technology was employed to deposit Ni60A/Cr3C2 composite coatings with the rare-earth oxide Y2O3 onto 60Si2Mn steel surfaces. The effects of different amounts of Y2O3 on the wear resistance of Ni60A/Cr3C2 composite coatings were evaluated. Scanning electron microscopy (SEM), X-ray diffraction, X-ray photoelectron spectroscopy, and 3D morphological analysis were used to investigate the microstructure, microhardness, elemental distribution, and tribological properties of the coatings. The ideal amount of Y2O3 to add to the mixtures to enhance the wear resistance was determined. The results showed that the coating containing 1.5% Y2O3 and Ni60A/Cr3C2 composite powder exhibited superior overall performance. Coatings with different amounts of added Y2O3 exhibited similar phase compositions, mainly consisting of γ-Ni-based, Ni2Si, M7C3 (M = Cr, Mn), and M23C6-strengthened phases. SEM analysis revealed that the coating with 1.5% Y2O3 exhibited excellent metallurgical bonding with the substrate. In addition, the coating exhibited finer grains, increased density, a more uniform distribution of coating elements, and a microhardness of 990 HV. Fewer grooves and smoother abrasions were observed after the wear test. The wear amount and depth were 14 × 10−4 g and 8.97 μm, which were 22.2% and 55.4% lower than the coating without added Y2O3, respectively. The tribological behavior indicated that adding the appropriate amount of Y2O3 facilitated the grain boundary consolidation while enhancing the adhesive properties of the oxide film, thereby increasing the wear resistance of the coating.