摘要本文主要研究的是工业纯钛TA2激光-GMAW复合焊接的焊接工艺，并且研究分析了其焊接接头的微观组织和力学性能。首先，通过改变焊接工艺参数的数值对3mm厚工业纯钛TA2进行激光-GMAW焊接，分析焊接工艺参数对接头焊缝的熔深、熔宽和余高的影响，进而确定出工业纯钛TA2的激光-GMAW复合焊接的最佳焊接工艺参数。研究最佳焊接工艺参数下工业纯钛TA2的激光-GMAW复合焊接接头的微观组织，分析出焊接接头各部分的组织成分。通过拉伸测试和硬度测试，对工业纯钛TA2的激光-GMAW复合焊焊接头的显微组织及力学性能进行了研究分析。87003

  通过焊接实验可以发现，当激光-GMAW复合焊接工业纯钛TA2的激光功率为2000W，焊接速度为20mm/s时，电弧电流为100A时，焊接接头的焊缝质量最佳。在焊接功率和电弧电流不变的条件下，接头焊缝的上熔宽和下熔宽会随着焊接速度的增大呈现出先减小后增大的变化趋势，而熔深和余高都呈现出减小的变化趋势。同理，当电弧电流和焊接速度不变时，接头焊缝的上熔宽和余高会随着焊接功率的增大而减小，而下熔宽和熔深随着焊接功率的增大而增大。最后，在焊接速度和焊接功率不变的前提下，可以发现，接头焊缝的上熔宽和下熔宽会随着电弧电流的增大呈现出先减小后增大的变化趋势，而熔深和余高都呈现出增大的变化趋势。

毕业论文关键词：工业纯钛；激光-GMAW复合焊接；焊接工艺参数；微观组织；力学性能

Abstract In this paper，the industrial pure titanium TA2 laser-GMAW compound welding  process is researched and the microstructure and mechanical properties of welded joints are summarized．First of all，the 3mm-thick industrial pure titanium TA2 is welded with laser-GMAW by changing the value of welding parameters，determine the best of industrial pure titanium TA2 laser-GMAW compound welding process parameters．Research under the optimal welding process parameters of laser-GMAW compound welding of industrial pure titanium TA2 joint microstructure，analysis of the welding joint microstructure composition of each part．By tensile test and hardness test，analysis of industrial pure titanium TA2 laser-GMAW compound welded joint mechanical properties．

The test results show that the laser welding of industrial pure titanium TA2 laser power is 2000 w，the welding speed is 20mm/s and arc welding current is 100A，the surface of the weld is silvery white，uniform weld stripes，weld quality best．What can be founded in welding experiments is that the weld width and the lower weld width will be presented a trend of decreases and then increases with the increasing welding speed when the arc welding current and the welding power never change，but the melt deep and the reinforcement are showing decreasing trends．Similarly，under the premise of the welding speed and the arc welding current never changing，the weld width and the reinforcement decrease when the welding power increases，while the lower weld width and penetration of welding power with the increase increases．Finally，the weld width and the lower weld width will be presented a trend of decrease and then increase with the increasing the arc welding current when the welding speed and the welding power never change，but the melt deep and the reinforcement are showing increasing trends．

Keywords: laser-GMAW compound welding；industrial pure titanium TA2；welding process parameters；microstructure；mechanical properties

目  录

第一章 绪论 1

1。1研究的背景及意义 1

1。2 工业纯钛TA2基本特性及焊接特点 2

1。2。1 工业纯钛的分类