TC17钛合金焊接接头组织与力学性能分析

对TC17钛合金薄板采用氩弧焊和电子束焊两种焊接方法焊接,进行了拉伸试验,结合拉伸试验结果与断口形貌,对比分析了力学性能与焊接接头组织之间的联系。研究结果表明,TC17钛合金在经历TIG焊接热循环后,焊缝及靠近焊缝的热影响区晶粒粗化,电子束焊接头热影响区较窄且没有粗晶区形成;两种焊接试样抗拉强度均与母材等强;相对延伸率有所降低,主要是热影响区及焊缝的组织变化所致;氩弧焊焊缝组织较不均匀性更为显著。

Microstructure and Mechanical Properties of Welded Joint of TC17 Titanium Alloy

TC17 titanium alloy sheet is welded with tungsten inert gas arc welding (TIG) and electron beam welding (EBW),and tensile tests are carried out.Based on tensile test result and fracture morphology,relationship between mechanical properties with microstructure of welded joint is analyzed.The research results show,when TC17 alloy is heated by TIG arc,grains in the weld bead and heat affected zone (HAZ) are badly coarsening.The heat affected zone of EBW is relatively narrow,and there is no coarse grain zone.Tensile strength of two welding methods are both strong as the base metal and the relative elongation is deceased,mainly because of the microstructure change of the heat affected zone and the weld.Compared with EBW,the micro structure of TIG joint is more coarse.