冷作硬化不锈钢对接接头组织与性能分析

Analysis of structures and properties of cold rolling stainless steel butt welding joints

为了提高奥氏体不锈钢强度,通常采用冷作硬化工艺进行生产。对轨道车辆用冷作硬化2 mm的SUS301L-HT和SUS301L-DLT奥氏体不锈钢材料的焊接性进行研究,结果表明两种材料焊接性良好,但焊接后焊缝接头强度均低于母材强度,HT材料焊接接头效率约为80%;DLT材料焊接接头效率约为93%;焊缝区域硬度低于母材;两种材料热影响区及熔合区微观组织类似,焊缝中心为树枝晶,熔合区为柱状晶,热影响区为粗大的等轴晶。

Austenitic stainless steel is produced by cold rolling process in order to increase the material＇s strength. In this paper,the welding properties of cold rolling austenitic stainless steel （2 mm-SUS301L-HT and 2 mm-SUS301L-DLT） were investigated. The results indicated that these two materials have good welding properties. But the strength is lower than the patent material, strength of HT material joint is about 80 percent of patent material,strength of DLT material joint is about 93 percent of patent material. Hardness of Joints is lower than patent material. HT joint＇s Micro-structure is similar to DLT joint,in the middle of welding joint is dentrites, fusion zone is columnar crystals, heat affected zone is equiaxed grains.