• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2017, Vol. 53 ›› Issue (18): 57-63.doi: 10.3901/JME.2017.18.057

• 材料科学与工程 • 上一篇    下一篇


王敏, 张会杰, 于涛, 朱智, 张骁, 杨广新   

  1. 中国科学院沈阳自动化研究所机器人学国家重点实验室 沈阳 110016
  • 收稿日期:2016-04-12 修回日期:2016-11-01 出版日期:2017-09-20 发布日期:2017-09-20
  • 通讯作者: 张会杰(通信作者),男,1985年出生,博士,副研究员.主要研究方向为机器人化搅拌摩擦焊技术.E-mail:zhanghuijie@sia.cn
  • 作者简介:王敏,女,1963年出生,博士,研究员.主要研究方向为机器人辅助搅拌摩擦焊设备及工艺技术.E-mail:mwang@sia.cn
  • 基金资助:

Influence and Affecting Mechanism of Tool Pin Geometrical Configuration on Weld Formation during Non-tilting Friction Stir Welding

WANG Min, ZHANG Huijie, YU Tao, ZHU Zhi, ZHANG Xiao, YANG Guangxin   

  1. State Key Laboratory of Robotics, Shenyang Institute of Automation, Chinese Academy of Sciences, Shenyang 110016
  • Received:2016-04-12 Revised:2016-11-01 Online:2017-09-20 Published:2017-09-20

摘要: 无倾角搅拌摩擦焊工艺是保障平面二维及空间三维复杂焊缝焊接质量的关键技术。分别采用含有光面搅拌针、光面带切台搅拌针和螺纹带切台搅拌针的焊具进行无倾角焊接试验,对比研究焊缝形貌、缺陷分布和接头性能,以期阐明搅拌针几何形态对无倾角搅拌摩擦焊焊缝的影响及其机制,从而为无倾角搅拌摩擦焊工艺的高质量应用奠定技术基础。试验结果表明,在无倾角焊接条件下,光面搅拌针容易导致焊缝根部出现孔洞缺陷,难以形成优质接头;带切台搅拌针增强了焊缝中上部材料的塑性流动,由此间接促进了焊缝根部匙孔的填充,在较低焊速下可以获得无缺陷接头;搅拌针螺纹结构直接增强了焊缝根部材料的塑性流动,因而能在更宽的参数范围内形成无缺陷接头。与光面搅拌针相比,搅拌针切台结构增大了接头软化区宽度,提高了焊缝上部的软化程度,所得无缺陷接头的抗拉强度最高可达母材的86%。对比而言,在带切台搅拌针上进一步加工螺纹能够降低焊接热软化效应,减小软化区宽度并提高焊核区硬度,接头最高强度系数由此增大到了90%。

关键词: 焊缝成形, 几何形态, 搅拌针, 无倾角搅拌摩擦焊

Abstract: Non-tilting friction stir welding (NT-FSW) is the critical technique for the joining of the plane two-dimensional and spatial three-dimensional complex structures. In order to illuminate the influence and affecting mechanism of tool pin geometrical configuration on the weld formation during NT-FSW and to provide technological guidance for the high-quality applications of NT-FSW process, the welding tools with smooth pin, smooth-flattened pin and threaded-flattened pin are utilized to carry out NT-FSW experiments in the present paper, and the weld morphology, defect distribution and joint properties are comparatively investigated. The results indicate that for NT-FSW process it is difficult to produce sound joints by using the smooth tool pin since the void defect tends to be formed at the weld root. The flat feature of tool pin enhances the material plastic flow at upper and middle parts of weld and thus indirectly promotes the filling of keyhole at the weld root, leading to the formation of defect-free joints at lower welding speeds. The threads of tool pin directly improve the material flow levels at the weld root and can produce defect-free joints in a wider process parameter range. Compared with the smooth tool pin, the flattened tool pin widens the softening region and improves the softening levels at the weld top, leading to a maximum strength efficiency of 86% for the defect-free joints. By contrast, the threads further machined on the flattened tool pin can control the local softening occurring in FSW, which narrows the softening region width and improves the hardness of nugget. Due to this, the maximum strength efficiency is improved up to 90%.

Key words: geometrical configuration, non-tilting friction stir welding, tool pin, weld formation