基于能量-冶金联合调控的钢/铌激光焊接工艺研究摘 要本文是关于添加铜填充层对钢/铌异种合金激光焊接接头性能影响的研究。研究中使用了金相显微镜、SEM、XRD等仪器对获得的焊接接头的宏观形貌、微观组织和相组成进行了观察和分析。并使用电子万能试验机对焊接接头的抗拉强度进行测量。82246

研究结果表明，添加铜填充层的焊接接头中没有金属间化合物生成，比不添加填充层的钢/铌激光焊接获得的焊接接头更好；不添加填充层的钢/铌激光焊接接头的焊缝区域主要由奥氏体组成，焊缝中心组织为树枝晶。而添加了铜填充层的钢/铌激光焊接接头中的焊缝金属主要是铜基固溶体；不添加填充层的钢/铌激光焊接接头的抗拉强度为133MPa，其抗拉强度仅为304奥氏体不锈钢的24。6%。添加了铜填充层的钢/铌激光焊接接头的抗拉强度为250MPa，其抗拉强度是304不锈钢的46。3%，纯铜的64。6%，约为不添加填充层钢/铌激光焊接接头抗拉强度的两倍。同时，添加铜填充层比添加其他单一金属填充层和添加两种复合金属填充层的钢/铌激光焊接接头的抗拉强度都要高。

毕业论文关键词：钢/铌异种合金；激光焊接；铜填充层

AbstractThis paper involves the influence of the laser welded steel/niobium joints with Cu element 。Test instrument includes metallurgical microscope ,SEM ,XRD and EDS analysis。 We use the test instrument to analyze morphology and fracture morphology 。T he tensile strength of the welded joint was measured electronic universal testing machine。

Research results show that the laser welded steel/niobium joints with Cu element is better than the one joints without it in appearance of weld 。Steel/niobium compound welding is composed of austenite grain and distribution of a small amount of ferrite 。The seam of the laser welded steel/niobium joints with Cu element is mainly composed of copper based solid solution 。Phase composition is Cu based solid solution 。Steel/niobium laser welding joint tensile strength can reach 133MPa is equal to 24。6% of the stainless steel 。The laser welded steel/niobium joints with Cu element tensile strength can reach to 250MPa is equal to 46。3% of the stainless steel and relative to Cu 。At the same time ,the tensile strength of the steel/niobium laser welded joint with the Cu element is higher than that of the other single metal filler layer and two kinds of composite metal filler layer。 

Key words: steel/ niobium dissimilar alloy; laser welding; copper filling layer

目录

第一章绪论 1

1。1 选题的背景和意义 1

1。2 不锈钢与铌的焊接性 1

1。2。1不锈钢与铌的物理性质分析 2

1。2。2 根据冶金学分析不锈钢与铌的焊接性 2

1。3 不锈钢与铌的焊接研究现状 4

1。3。1 熔化焊 4

1。3。2 钎焊 5

1。3。3 爆炸焊 6

1。3。4 熔钎焊 7

1。4 课题主要研究内容 8

第二章实验材料、设备和方法 9

2。1 实验材料 9

2。2激光焊接设备 10

2。3 激光焊接试验 11

2。3。1焊前准备 11

2。3。2 焊接过程