Investigating the Effects of Plasma-Sintered WC-17Co Morphology and Content Changes on the Properties of Laser-Melted Fe-Based Coatings

Abstract In order to investigate the influence of the shape of the powder raw material on the coating properties, this paper investigates the plasma-sintered WC particles added to Fe-based powder to prepare coatings, and characterization methods such as coating microstructure, microhardness, and friction and wear are examined. The results show that with the increase of the mass fraction of added WC-17Co, the physical phases of the coatings appeared Fe 3 W 3 C 3 and Co 3 W 3 C 3 , and at the same time, the microstructure of the coatings had a dense and homogeneous grain structure without obvious defects, and irregular aggregation of WC particles was clearly observed, and fine WC precipitates dispersed in the coatings were also observed. The hardness of the coating increases with the increase of WC-17Co content, and the spherical shape of the powder has a better improvement effect. With the addition of 30% WC-17Co, the hardness of the coating reaches 800HV0.2, which is 60% higher than that of the unadded coating. Spherical WC particles with 30% addition showed a more significant improvement, with a wear rate of 10-8, which was significantly better than that of non-spherical particles. Spherical particles have a smoother particle surface, which facilitates inter-particle movement and provides better spatial accumulation of powders, and at the same volume, the WC content of the spherical form of the powder is higher.