利用脉冲熔化极气体保护焊技术,采用UTP A DUR600耐磨焊丝,在45CrNiMoVA钢上制备耐磨堆焊层,用带有能谱仪(EDS)的扫描电子显微镜(SEM)观察分析堆焊层的组织形貌,测定堆焊层的硬度,评价堆焊层的耐磨性。结果表明:堆焊层的主要组织为奥氏体和二次渗碳体,堆焊层的硬度较基体有了较大提高,堆焊层较基体有更加优良的耐干滑动摩擦磨损的性能,堆焊层中二次渗碳体的存在,奥氏体的加工硬化以及碎屑在摩擦作用下的碎化、动态氧化和热压烧结,是堆焊层具有更优异磨损性能的原因。
The wear resistant welded surfacing layer is prepared on 45CrNiMoVA steel with UTP A DUR600 wear resistant weld wire by means of pulse metal inert-gas arc welding technology. The microstructure of welded surfacing layer is observed and analysed by scanning electronic microscopy(SEM); And the microhardness and wearing resistance are tested. The results show that the microstructure of welded surfacing layer is mainly composed of austenite and secondary cementite; The welded surface layer has higher microhardness and more excellent wearing resistance than 45CrNiMoVA steel substrate; The existence of hard secondary cementite, the work hardening of austenite and fragmentation, dynamic oxidation and hot pressed sintering of abrasive dust are mainly reasons which make welded surface layer possess more excellent wearing resistance.