TIG电弧增材制造308L不锈钢的显微组织与力学性能分析

Microstructure and Mechanical Properties of 308L Stainless Steel Made by TIG Arc Additive Manufacturing

采用TIG电弧增材制造的方法成形了308L不锈钢的直壁件,研究了其显微组织和力学性能。利用奥氏体不锈钢的凝固模式预测显微组织,通过SEM和EDS能谱分析成形件的显微组织。结果表明:预测组织和实际组织一致,为奥氏体和少量铁素体。直壁件的底部和顶部位置显微硬度高于中部组织的,底部最高,顶部次之。从成形件上取水平方向的试样进行拉伸试验,断裂形式为韧性断裂,成形件的抗拉强度最小值达到520.19 MPa,伸长率最小值达到41.7%。

308L stainless steel straight wall pieces were fabricated by TIG arc additive manufacturing. The microstructure and mechanical properties were studied. The solidification mode of austenitic stainless steel was used to predict the microstructure, and the microstructure of the forming part was analyzed by SEM and EDS. The results show that the predicted microstructure is consistent with the actual microstructure, which is austenite and a small amount of ferrite. The microhardness of the bottom and top of the additive part is higher than that of the middle structure, that of the bottom is the highest, and that of the top is the second. The specimens were sampled from the part in horizontal direction for tensile test, and the fracture mode is ductile fracture. The minimum tensile strength of the forming part is 520.19 MPa, the minimum elongation is 41.7%.