原位自生TiC颗粒对铁基耐磨堆焊金属的影响

摘要

In order to study the influence of in-situ synthesis TiC particles on microstructure and properties of surfacing layer, the Fe-Cr-Ti-C surfacing alloy was prepared on the surface of Q235 steel with the flux cored arc surfacing method.The surfacing alloy was characterized with X ray diffractometer(XRD), scanning electron microscope(SEM)and wet sand wear testing machine.The results show that the addition of Ti element can generate TiC hard phase particles with the in-situ synthesis mode in the surfacing layer, and promote the formation of M7C3 hard phase, which can play the role of refining grain size.When the amounts of the generated TiC and M7C3 hard phases are large and the hard phases disperse in the metal matrix, the hard phases can play the role of corresponding wear resistant skeleton, and thus the wear resistance of surfacing metal gets enhanced.When the mass fraction of Ti element in the cored wire is 7%, the surfacing layer has the optimal performance, the hardness value of surfacing layer is 61.6 HRC, and the wear loss is 0.3904g.%为了研究原位自生TiC颗粒对堆焊层组织与性能的影响,采用药芯焊丝明弧堆焊方法在Q235钢表面制备了Fe-Cr-Ti-C堆焊合金.利用X射线衍射仪、扫描电子显微镜、洛氏硬度计和湿砂磨损试验机对堆焊合金进行了分析.结果表明,加入的Ti元素可在堆焊层中原位生成TiC硬质相颗粒,并促进M7C3硬质相的生成,从而起到细化晶粒的作用.当生成的TiC和M7C3硬质相数量较多且弥散分布于金属基体中时,这些硬质相可起到相应的抗磨骨架作用,从而提高了堆焊金属的耐磨性.当药芯焊丝中Ti元素的质量分数为7%时,堆焊层性能最佳,其硬度值为61.6 HRC,磨损量为0.3904g.