论文部分内容阅读
以镁基焊丝为填充材料,采用双光束激光熔钎焊的方法对AZ31B镁合金/不锈钢的焊接特性进行了研究。分析了不同工艺参数对焊缝成形、接头力学性能和断裂行为的影响。结果表明,采用双光束进行填丝熔钎焊能够获得较满意的外观成形,无明显缺陷,焊接工艺范围较宽。接头拉伸均断裂于熔化焊的镁侧焊缝及热影响区(HAZ),最大剪切强度为193MPa,达到镁合金母材强度的71%。组织分析发现焊缝和HAZ的晶粒粗大,成为接头的薄弱部位,是接头失效的主要原因。钎焊侧界面发生了冶金反应,界面处生成1～2μm的反应层。
The welding characteristics of AZ31B magnesium alloy / stainless steel were studied by using Mg-based welding wire as filler and dual-beam laser brazing welding. The effects of different process parameters on the weld formation, mechanical properties and fracture behavior of the joint were analyzed. The results show that the use of double beam filler wire braze welding can get a more satisfactory appearance of forming, no obvious defects, a wide range of welding process. Tensile joints were broken in the melting side of the magnesium weld and heat-affected zone (HAZ), the maximum shear strength of 193MPa, to achieve the strength of magnesium alloy base material 71%. Tissue analysis found that the weld and HAZ coarse grains, become weak joints, joints is the main reason for the failure. A metallurgical reaction occurred at the brazed side interface and a reaction layer of 1 to 2 μm was formed at the interface.