公路钢桥复合板的焊接组织与性能研究

Study on Welding Microstructure and Properties of Composite Plate of Highway Bridge Steel

对公路钢桥复合钢板进行了电弧焊和钨极氩弧焊,考察了3种焊接接头的力学性能和焊接接头区域的显微组织变化,对热影响区中的铁素体含量和奥氏体含量进行了表征。结果表明,3种焊接接头中,焊接接头B具有最佳的强度和塑性结合,且焊接接头A和焊接接头B的抗拉强度要高于焊接接头C,即采用电弧焊工艺得到的焊接接头的性能要优于电弧焊+钨极氩弧焊焊接接头。2205钢与过渡层焊接接头A和焊接接头B中的热影响区宽度较为接近,且都小于焊接接头C中的热影响区宽度。16Mn钢与过渡层焊缝界面的脱碳层宽度从大至小依次为:焊接接头A>焊接接头B>焊接接头C。

Structure composite plate used in steel bridge was welded with electric arc welding and argon tungsten arc welding. The mechanical properties and microstructure of the three kinds of welding joints were studied and the ferrite and austenite content in the heat affected zone was characterized. The results show that, among the three kinds of welding joints, welding joint B has the best combination of strength and plasticity, and the tensile strength of welding joint A and welding joint B is higher than that of welding joint C, that is, the welding joint with electric arc welding process is superior to that with electric arc welding ＋ tungsten electrode argon arc welding. The width of the heat affected zone of 2205 steel and transition layer in welding joint A is close to welding joint B, and both are less than welding joint C. The width of decarburization layer in 16Mn steel and weld transition layer interface from big to small is as follows： welding joint A〉 welding joint B 〉 welding joint C.