To reveal the abrasion behavior of NbC reinforced Ni-based alloy coatings

NbC-reinforced Ni-based alloy coatings with different Nb/C ratios were prepared by laser cladding technology. The phase composition

microstructure

and distribution of in-situ generated NbC particles in the coatings were analyzed using scanning electron microscope (SEM)

energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). The microhardness and abrasion resistance of the coatings were analyzed. The results show that the in-situ generated NbC particles are uniformly distributed in the coatings with a volume proportion up to 49.264%. As the Nb content increased

the morphology of NbC changed from cross-shaped to spherical and rectangular. Dispersion strengthening and solid solution strengthening are the main strengthening mechanisms in the coatings. The hardness of coatings increased in accordance with the growth of the Nb/C ratio. The abrasion resistance of coatings under wet sand abrasion conditions is positively correlated with hardness. Overall

the coating with 45 wt.% Nb and 35 wt.% Cr3C2 have the highest NbC content

while the coatings with 50 wt.% Nb and 30 wt.% Cr3C2 exhibits the highest hardness and wear resistance.