The Spherical Casting WC Powder and its Application in Laser Surface Alloying Treatment

The spherical casting WC powder is a kind of new potential wear-resistance ceramic material. In this paper, its chemical composition, surface morphology, microstructure, phase, microhardness and some powder characteristics were investigated, and then the powders were applied in laser surface alloying treatment on medium carbon steel. The results indicate that the spherical WC powder consists of (wt.%) 94.06 W, 4.03 C and 1.91 other elements including Fe, V, Cr and Nb. Most of powder particles have regular spherical shape and smooth surface, and the microstructure is acicular eutectic of WC and W2C, which leads to high microhardness of 2812 HV. The fluidity of powders is 5.97 s/50g, and the apparent density of powders is 10.1 g/cm3. The laser alloyed layer is characterized by dendritic primary phase, ledeburite microstructure and some residual WC particles. The laser surface alloying treatment with adding material of spherical casting WC powder can enhanc the abrasive wear resistance of medium carbon steel by over 200%.