SUS 301L不锈钢冷金属过渡焊搭接接头焊接工艺、微观组织及力学性能

Welding technology,microstructure and mechanical properties of SUS301L stainless steel lap welded joint by cold metal transfer technology

随着我国轨道交通行业的飞速发展,车体减重对于节省能源有着重大意义。利用CMT冷金属过渡焊接技术对4—0.8 mm SUS301L-MT不锈钢搭接接头进行工艺研究,获取最优工艺参数;同时,观察焊接接头的宏观形貌、微观组织,测量其力学性能及变形。结果表明,在最优工艺参数下,焊缝成形美观,无明显缺陷,焊缝区组织主要为奥氏体柱状晶和枝晶状铁素体;焊接接头最大拉伸剪切力达到22 234.42 N,硬度测试最小值均出现在焊缝区;此外,焊后试板呈现波浪变形,最大Z方向变形量出现在试板边缘。

With the rapid development of the rail transportation industry in our country,the weight reduction of the train body has great significance for energy saving. The 4-0.8 mm lap joints of SUS301L-MT stainless steel is studied by using CMT welding technology ,and the optimized wehting parameters are obtained;Macro morphology and microstructure observation,mechanical properties and deformation measurement of welded joints are carried out. The results show that under the optimized parameters,the weld is well formed without obvious defects. The microstructure of the weld zone is mainly austenile columnar crystal and dendritic crystal ferrite. Besides,the maximum tensile-shear force of the welded joint reaches 22 234.42 N,and the minimum value of the hardness test occurs in the weld zone. After wehling,the sample appears wave deformation,and the maximum Z direction defurmation occurs at the edge of the sample. Key words： SUS301L-MT stainless steel ; CMT cold metal transfer; micrnstrueture ; mechanical properties ; deformation measurement