• CN:11-2187/TH
  • ISSN:0577-6686

›› 2014, Vol. 50 ›› Issue (16): 135-139.

• 论文 • 上一篇    下一篇



  1. 兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室
  • 发布日期:2014-08-20

Microstructure and Properties of Ti6Al4V-T2 Lap Welded Joints by Cold Metal Transfer Technology

FENG Zhen;CAO Rui;CHEN Jianhong   

  1. State Key Laboratory of Gansu Advance Non-ferrous Metal Materials, Lanzhou University of Technology, Lanzhou 730050
  • Published:2014-08-20

摘要: 采用冷金属过渡(Cold metal transfer, CMT)技术,以镍铝青铜ERCuNiAl焊丝作为填充材料,对钛合金Ti6Al4V和纯铜T2异种金属薄板进行钛板在上铜板在下的搭接连接。使用扫描电镜和能谱分析研究焊接接头的显微组织和反应界面金属间化合物的组成,并通过横向拉伸试验对接头的力学性能进行评定。研究结果表明,冷金属过渡技术可以实现于钛/铜异种金属的有效连接。焊接过程中电弧比较稳定,焊缝成形良好。在电弧热的作用下,铜板完全熔透,与焊缝金属形成铜-焊缝界面,钛板部分熔化,铜板和焊丝熔化包围在钛板的周围,形成了钛和焊缝的三个界面,提高了接头的力学性能。钛侧金属间化合物层包含TiCu、TiAl、Ti2Cu、AlCu2Ti和铜基固溶体等多种金属间化合物。拉伸试验时,断裂发生在铜母材的热影响区,拉剪强度可达200 MPa。

关键词: 钛合金;纯铜;异种金属焊接;冷金属过渡技术;搭接接头

Abstract: The lap-shear joint configuration that the titanium alloy Ti6Al4V sheet is placed on the top of the pure copper T2 sheet is carried out. 1 mm thick titanium alloy Ti6Al4V is joined to 1 mm thick pure copper T2 using ERCuNiAl filler wire by cold metal transfer(CMT) welding technology. Microstructure and intermetallic compounds of the welded joints are examined by scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). The mechanical properties are characterized by tensile-shear tests. Results indicate that the welding process is stable and the continuous and uniform welded joint is formed. Satisfied lapped joint between titanium alloy Ti6Al4V and pure copper T2 can be achieved by CMT welding method. Copper sheet and welding wire are melted, and then copper-weld interface is formed. Titanium sheet is partially melted, copper sheet and welding wire melting is surrounded around titanium sheet, so three titanium-weld interfaces are formed. Ti-Cu welded interface is composed of an intermetallic compounds layer of TiCu, TiAl, Ti2Cu, AlCu2Ti and copper base solid solution. The joint has tensile shear strength of 200 MPa, and fractures with plastic fracture mode in the copper heat affected zone (HAZ).

Key words: titanium alloy;pure copper;dissimilar metals welding;cold metal transfer;lap welded joint