Microstructure and performance optimization of laser cladding nano-TiC modified nickel-based alloy coatings

Abstract

In this study, different alloy powders containing nano-sized TiC were prepared using a combination of mixed ball milling adsorption, electroless Ni-P-TiC, and Ni-B-TiC plating techniques. The effects of different nano-TiC addition methods on the microstructure, wear resistance, and corrosion resistance of laser-coated nickel-based self-fusing alloy coatings were comprehensively studied. The effects of the nano-TiC method on the microstructure, wear resistance, and corrosion resistance of laser-coated nickel-based self-fusing alloy coatings were comprehensively studied. The results show that agglomerated TiC particles appeared in the coatings prepared with ball-milled powder. In contrast, the coatings produced by introducing nano-sized TiC through the chemical plating methods exhibited a uniform distribution of the TiC phase. The coatings prepared with Ni-B-TiC plating powder showed a bimodal microstructure and most of the TiC particles are distributed at grain boundaries, which hinders grain growth and refines the microstructure of the coating. The corrosion resistance of the Ni2 coating prepared with ball milling adsorbed nano TiC powder shows the best corrosion resistance. The wear resistance of the Ni4 coating prepared with the Ni-B-TiC plating powder was significantly better than that of the other samples. This study provides an effective way to improve the wear or corrosion resistance of laser cladding nickel-based self-fluxable alloy coatings.