高温合金-不锈钢异种金属光纤激光焊接试验研究

采用光纤激光对GH3128与304不锈钢进行对接焊,研究了焊接速度、激光作用位置等工艺参数对焊缝成形及接头力学性能的影响规律。结果表明:通过工艺参数优化,可以获得无气孔、裂纹等缺陷的焊接接头。焊接速度较低时,焊缝上下部的熔宽较大,随焊接速度的提高,焊缝下部的熔宽减小到与中部相当,随激光作用位置向不锈钢侧靠近,接头强度和延伸率降低。当激光作用于GH3128侧,在焊接速度小于2m/min时,焊接接头拉伸试验时断于304不锈钢母材:当焊接速度为3m/min时,焊缝存在未熔合,接头强度仅为母材的37%。

Experimental Investigation on Fiber Laser Welding Stainless Steel 304 to Super Alloy GH3128

The influence of laser welding parameters, such as welding velocity and welding position, on weld shaping and mechanical properties of dissimilar SS304 and Super Alloy GH3128 was investigated. The welding experiment adopted the butt joint using fiber laser. Result shows no crack and porosity existing in weld after parameter optimization. Weld width in the top and bottom is wider than that in the middle at low welding speed. However, at high welding speed, the wider weld was only observed in the top. Mechanical tests indicate that strength and elongation decrease with welding position moving to SS304. At the welding speed of 2 m/min and welding position close to GH3128, sample fractured at base metal SS304. When the welding speed is increased to 3 m/min, the strength of the joint is only 37% of base metal. The sample fractured on the weld and the incomplete fusion was observed.