Effects of Surfacing Technologies on Microstructure and Wear Resistance of High Chromium Alloy Powder Surfacing Layers

Two surfacing technologies, welding wire-alloy powder surfacing and welding wire-alloy powder block surfacing, were used to prepare high chromium alloy powder surfacing layers on Q235 steel surface, and the microstructure and wear resistance of the surfacing layers were studied by scanning electron microscopy, X-ray diffraction, wear and hardness testing. The results show that the microstructure of surfacing layers prepared by the surfacing technologies mainly consisted of austenite, ferrite and carbide. The welding wire-alloy powder block technology had many advantages, such as less sputtering, more carbide precipitate and good slag detachability. The hardness and wear resistance of the surfacing layers prepared by welding wire-alloy powder block surfacing technology were better than those by welding wire-alloy powder block surfacing technology, and were 3 times and 2 times higher than those of Q235 steel, respectively.