堆焊工艺对高铬合金粉体堆焊层组织及耐磨性能的影响

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

分别采用焊丝粉末堆焊和焊丝粉块堆焊工艺,在Q235钢基体表面制备了高铬合金粉体堆焊层,利用扫描电镜、X射线衍射仪、磨料磨损试验机和洛氏硬度仪等对两种堆焊层的微观组织、硬度及耐磨性能等进行了研究。结果表明:两种工艺制备的堆焊层组织均由奥氏体、铁素体和碳化物组成;其中采用焊丝粉块堆焊时的飞溅少、碳化物析出多、脱渣性好,其制备堆焊层的洛氏硬度和相对耐磨性比焊丝粉末工艺的好,且分别为Q235钢的3倍和2倍。

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 wireaIloy 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.