不同焊接工艺对SUS301L-MT不锈钢接头组织和力学性能的影响

Effects of Different Welding Processes on Microstructure and Mechanical Properties of SUS301L-MT Stainless Steel Joints

采用活性气体保护电弧焊(MAG)、激光焊和激光-MAG复合焊三种焊接方法,分别对SUS301L-MT不锈钢进行了对接焊,分析比较了三种不同焊接工艺对接头组织和力学性能的影响。结果表明,三种焊接工艺下得到的焊缝接头均为δ铁素体和奥氏体的双相组织,MAG焊接头的热影响区宽度达到了3mm,而激光焊和激光-MAG复合焊的热影响区宽度仅为1mm;三种焊接工艺下的接头残余应力峰值均分布在焊趾位置,MAG焊接头具有最高的纵向和横向残余应力峰值;激光-MAG复合焊接头的抗拉强度最高,达到906 MPa。

The butt welding of SUS301L-MT stainless steels is conducted by means of the metal active gas arc welding （MAG）, laser welding and laser-MAG hybrid welding, respectively, and the effects of these three different welding processes on the microstructure and mechanical properties of joints are investigated and compared. The results show that, the welded joints obtained under these three different welding processes are all duplex-phase structures with δ-ferrite and austenite. The width of the heat affected zone of MAG welded joints has a size of 3 mm, while both that of the laser welding and laser-MAG welded joints are only 1 mm. All the residual stress peaks under three welding processes distribute at weld toe, and the MAG welded joints have the highest longitudinal and transverse residual stress peak values. The laser-MAG welded joints show the highest tensile strength with a value of 906 MPa.