焊接距离对钛合金搅拌摩擦焊搅拌头磨损的影响

Influence of welding distance tool wear in friction stir welding of Ti-6Al-4V alloy

摘要:

采用搅拌摩擦焊对TC4钛合金热轧板进行焊接。通过失重法、3D影像仪和显微组织观察对TC4钛合金搅拌摩擦焊过程中，DZ22高温合金搅拌头磨损情况进行表征，研究了焊接距离对TC4钛合金搅拌摩擦焊搅拌头磨损的影响。实验结果表明:搅拌头磨损率与焊接距离成正相关，焊接距离达到180mm后搅拌头磨损严重，搅拌针长度缩短0.24mm，磨损率为0.97%；轴肩深度缩短0.4mm，磨损率为1.73%；搅拌头重量缩减0.15g，磨损率为0.74%。在FSW过程中，高温高压是造成搅拌头磨损的主要原因，搅拌头磨损类型主要有机械磨损、磨粒磨损、粘结磨损、氧化磨损，搅拌头的磨损往往是这几种磨损相互作用的结果。磨损的搅拌头会对焊缝造成污染形成孔洞等缺陷，从而影响焊接接头的性能。

Abstract:

The hot rolled plates of TC4 titanium alloys were welded by friction stir welding. The wear of tool of DZ22 superalloy stirring head characterization was carried out by weight loss measurement, 3D photographic technique and microscopic observations during friction stir welding of TC4 titanium alloy. This experiment has been studied Influence of welding distance tool wear in friction stir welding of TC4 alloy. The results indicate that severe tool wear deformation occurred after welding 180mm. The wear of tool is positively correlated with welding distance. The length of tool pin was shortened by 0.24mm and the wear rate was 0.97%. The depth of tool shoulder was shortened by 0.4mm and the wear rate was 1.73%. The weight of tool was reduced by 0.15g and the wear rate was 0.74%. In the process of friction stir welding of TC4, high temperature and high pressure are the main reasons for the wear of tool.Tool wear types are mechanical wear and tear、abrasive wear、adhesion wear and oxidative wear. The wear of tool is usually the result of the interaction of these wear. The wear of tool will pollute the FSW joints and form defects, thus affecting the performance of the FSW joints.