薄板Ti6Al4V钛合金电子束焊接组织性能分析

摘要

针对1.2mm厚Ti6A14V钛合金薄板进行了电子束焊接工艺试验,消除了薄板焊接常见的塌陷、熔切等缺陷,获得成形均匀和质量良好的焊缝；在光学显微镜和扫描电镜下观察了钛合金焊缝组织分布规律,焊缝区以马氏体为主,热影响区组织为α+β双态及少量马氏体；接头焊缝区显微硬度高,整体横向呈马鞍形分布.结果表明,薄板Ti6A14V钛合金电子束焊接接头拉伸强度与基材相当,但断后伸长率低于母材.%Ti6A14V titanium alloy sheet with 1.2 mm in thickness were welded by electron beam welding,and the weld appearance and welding quality are fine,and the common welding defects such as turn-through and excessive penetration in welding of thin plate do not occur. The microstructure of heat affected zon are ot + B with a little martensite,and martensite is mainly in the weld,which are analyzed by optics microscope and scanning electron microscopy. The microhardness of the joint presents the saddle distribution along the cross-section, and the maximum level appears in the weld. The results showed that the ultimate tensile stresses and yield stresses of the joints are equal to those of the base metals,but the elongate rate after the rupture of the joints is lower than that of the base metals.