马氏体不锈钢耐磨焊条及其性能

Martensitic stainless steel wear resistance electrode and its property

马氏体不锈钢具有高强度、良好的耐磨损性能以及一定的耐腐蚀性能。研制了一种马氏体不锈钢耐磨焊条,在低碳钢Q235上进行堆焊试验,分析堆焊接头的组织转变,并研究堆焊合金的耐磨性能。结果表明,该焊条具有良好的焊接工艺性能,堆焊层金属与母材结合良好,未出现裂纹等缺陷;堆焊层组织为板条马氏体+碳氮化物+少量残余奥氏体;碳氮化物沿马氏体基体和晶界析出,呈弥散分布,起到细晶强化和析出强化的作用;与母材相比,堆焊层金属的硬度和耐磨损性能明显提高,其磨损机制主要为显微切削和塑性变形。

Martensitic stainless steel exhibits a unique combination of high strength, good wear resistance and cnn＇nsion resistance. In this study,a kind of martensitic hardfacing electrode was developed,and overlayed on low carbon sheet steel Q235. The microstru- cture transformation of welded joint and the wear resistance of hardfacing alloy were investigated. It was proved that the electrode has a good welding peribrmance. Surfacing layer metal and base metal are combined well,without cracks,etc. The microstructure of hardfacing alloy contains lath martensite,carbonitride and a small amount of retained austenite. Carbonitrides precipitate in martensite matrix and grain boundary with diffuse distribution,which has the effect of fine-grain strengthening and precipitation strengthening. Compared with the base metal,the hardness and the wear resistance of surfacing layer metal are increased significantly. The main wear mechanism is microscopic cutting and plastic deformation.