FV520(B)马氏体不锈钢匹配自保护药芯焊丝的研制

Development of Self-shield Flux Cored Wire for FV520(B) Martensite Stainless Steel

基于成分与组织匹配设计原则,确定了FV520(B)马氏体不锈钢熔敷金属的合金系。结合焊缝金属合金化原理计算出需要向焊缝中过渡的合金元素种类及含量,设计并制备了FV520(B)马氏体不锈钢匹配用药芯焊丝,试焊后分析了接头性能。结果表明,用所研制的药芯焊丝焊接其接头的力学性能优异,抗拉强度达到911 MPa,屈服强度达到679.3 MPa,冲击功达到99.7J(20℃);焊缝组织主要为回火索氏体和板条马氏体,有少许残余奥氏体和析出碳化物,能与母材实现较好的匹配。

According to the principle of bilaterally matching in microstructure and composition for a weld joint to a matrix alloy, a self-shield flux cored wire was made of 304 stainless steel plate as feed metal with a selected flux especially for welding of FV520(B) martensite stainless steel. Then FV520(B) martensite stainless steel was welded with the prepared flux-cored wire by adopting appropriate welding process parameters. The weld joints were characterized in terms of microstructure and mechanical performance. The results show that the weld joints possess excellent mechanical properties: such as a tensile strength up to 911 MPa, a yield strength up to 679.3 MPa and an impact energy value 99.7 J(20℃).The microstructure of the weld joints consisted of tempered sorbet and lath marten site, as well as a little residual austenite and carbide precipitates, which can match well with parent material.