不同焊接工艺下2205双相不锈钢焊缝组织及性能对比

采用PAW不填丝打底焊接+TIG填丝盖面焊接、PAW不填丝打底焊+SAW盖面焊两种焊接工艺对2205双相不锈钢进行焊接，并通过力学试验、弯曲试验、金相组织观察及耐腐蚀性能试验，对焊缝的理化性能进行了检测。结果表明，两种焊接工艺焊缝的拉伸、弯曲试验结果均符合标准要求；SAW焊焊缝组织方向性较强，整体呈树枝状晶，TIG焊焊缝也存在树枝状晶，方向性较埋弧焊不明显，SAW焊热影响区组织呈连续带状分布，TIG焊热影响区组织呈间断条状分布，TIG焊母材区组织呈间断条状分布，SAW焊母材区组织呈连续带状分布；TIG焊盖面焊缝耐点蚀性能较优于SAW焊盖面焊缝耐点蚀性能。研究表明，TIG盖面焊焊缝组织及理化性能优于SAW盖面，但SAW焊生产效率比TIG焊生产效率高3倍多。可综合考虑应用工况及生产效率，选择焊接工艺。

Comparison of Microstructure and Properties of 2205 Duplex Stainless Steel Welds with Different Welding Processes

The 2205 duplex stainless steel was welded by two welding processes: PAW backing welding without filler wire + TIG wire filling cover welding and PAW backing welding without filler wire + SAW cover welding. The physical and chemical properties of the weld were tested by mechanical test, bending test, metallographic observation and corrosion resistance test. The results show that the tensile and bending tests results of the two welding processes meet the standard requirements. The whole structure of the microstructure of SAW weld is dendrite. There are also dendrites in TIG welding weld, which is less obvious than SAW. The microstructure of heat affected zone(HAZ) of SAW is continuous strip distribution, while that of TIG welding is discontinuous strip. The microstructure of TIG welding base metal is discontinuous strip distribution, and SAW welding base metal area is continuous strip distribution. The pitting corrosion resistance of TIG cover welding is better than that of SAW cover welding. The results show that the microstructure and physical and chemical properties of TIG welding are better than those of SAW welding, but the production efficiency of SAW welding is three times higher than that of TIG welding. The welding process can be selected by considering the application conditions and production efficiency.