Effect of Spherical Cast Tungsten Carbide Particles on Microstructure and Wear Resistance of Surfacing Layer

The spherical cast tungsten carbide particles with different contents and particle sizes was mixed with atomized Fe powder to prepare surfacing electrodes. The surfacing layer on Q235 steel substrate was obtained using oxygen-acetylene flame surfacing. The effect of content and particle size of spherical cast tungsten carbide on the microstructure, hardness and wear resistance of surfacing layer was investigated. The results show that there was an obvious melting phenomenon at the edges of spherical cast tungsten carbide in surfacing layer. The smaller the particle size of spherical cast tungsten carbide was, the more obvious the melting phenomenon was. The fish-bone ledeburite decreased with decrease of spherical cast tungsten carbide particles content, and the ledeburite became coarser with reduction of particle size of spherical cast tungsten carbide. The more spherical cast tungsten carbide particles content was, and the smaller particle size was, the higher the hardness was and the better the wear resistance of surfacing layer was.