310S耐热不锈钢TIG焊接接头组织与力学性能研究

Microstructure and mechanical properties of TIG welded 310S heatresistant stainless steel

采用钨极氩弧焊焊接方法,以不同的焊接工艺方案对310S奥氏体耐热不锈钢进行焊接试验.焊接试验完成以后观察焊缝成形的外观质量,采用金相显微镜对焊接接头进行显微组织观察分析,并进行力学性能测试.结果表明:在焊接电流I=140 A、焊接速度V=0.32 m/min的焊接工艺方案下,焊缝外观质量优良,焊接接头的组织和性能是最优的.在该焊接工艺方案下,焊缝区的晶粒组织细小均匀,拉伸试验的断裂位置在母材区域,并且焊接接头的抗拉强度为481 MPa,能达到母材抗拉强度的91%以上.

Different welding processes were conducted on the 310S austenitic heat-resistant stainless steel with the TIG welding method. After the completion of the welding, the weld formation and the welded joint microstructure are analyzed. The mechanical property is also tested with the metallographic microscope after that. The results show that the weld formation, the microstructure and property of the welded joint are optimal in the conditions as the welding current at 140A and the welding speed at 0.32m/min. In this welding process, the crystal grain organization of weld zone is excellent and more homogeneous. The fatigue beaked is on the zone of parent metal in the tension test, and the welded joint＇s extension strength is 481MPa and the strength of extension of the welded joint can reach to more than 91% of the parent metal＇s extension strength.