X100管线钢自保护药芯焊丝研制及焊接接头性能分析

Development of self-shielded flux cored wire for X100 pipeline steel and performance analysis of welded joints

基于成分匹配与组织匹配设计原则,确定了X100管线钢焊缝金属的合金系.结合焊缝金属的合金化原理,定量计算出需要向焊缝中过渡的合金元素种类及其含量,设计并制成X100管线钢匹配用自保护药芯焊丝.选用合适的焊接工艺参数进行试焊,并对焊接接头的性能进行分析.结果表明,所研制的药芯焊丝焊接接头的力学性能优异,抗拉强度达到795 MPa,屈服强度达到615 MPa,冲击吸收功达到47.7 J(-40℃);焊缝组织主要为板条状贝氏体和粒状贝氏体,另有少量针状铁素体穿插其中,能够与母材实现较好的组织匹配.

The alloy systems of weld metal of X100 pipeline steel were determined with the principle of composition match and structure match. Combined with the principle of weld metal alloying,the types and content of alloy elements which need to transit in the weld can be quantitatively calculated,based on which the flux-cored wire match to X100 pipeline steel was designed and made. The appropriate welding process parameters for welding and the according joint performance were also analyzed. The results showed that the flux-cored wire has excellent mechanical properties with the tensile strength up to 795 MPa,yield strength up to 615 MPa and impact energy value to47. 7J(-40 ℃). The microstructure of the weld metal consists of lath bainite,granular bainite,and little acicular ferrite,which can match well with base material.