ABSTRACT Filling Friction Stir Welding (FFSW) is an FSW completing process, in which the exit-holes at the end of friction stir welded lines are filled by a rotational semi-consumable pin. In the present study, combined 7.5 mm thick AA5456 rolled plates (5 mm) and pipes (2.5 mm) were successfully welded and filled by FFSW using a semi-consumable similar pin (5456) and semi-consumable dissimilar pins (7075 and 2024) on lap joint specimens. The effects of filling parameters, pin geometry, rotation speed and plunge velocity on the mechanical properties and microstructure of the joints were investigated by tensile and hardness tests. Optical Microscopy (OM) and Scanning Electron Microscopy (SEM) were implemented to study the microstructure and interfaces of the filled holes. Furthermore, preheating assessment was studied to cover technological issues. Finite element method was applied for FFSW simulation using DEFORM-3D commercial package. The optimized process parameters for AA5456 were obtained as the pin rotation speed of 800 rpm, plunge velocity of 50 mm/min and a similar material (AA5456) pin of cone angle 8°.

中文翻译：

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用自耗销修复AA5456管搅拌摩擦焊出孔

摘要 填充摩擦搅拌焊接 (FFSW) 是一种 FSW 完成工艺，其中搅拌摩擦焊接线末端的出口孔由旋转半自耗销填充。在本研究中，使用半消耗性类似销 (5456) 和半消耗性异种销 (7075 和 2024) 通过 FFSW 成功焊接和填充 7.5 毫米厚的 AA5456 轧制板 (5 毫米) 和管道 (2.5 毫米)在搭接试样上。通过拉伸和硬度试验研究了填充参数、销几何形状、旋转速度和插入速度对接头力学性能和微观结构的影响。实施光学显微镜 (OM) 和扫描电子显微镜 (SEM) 来研究填充孔的微观结构和界面。此外，还研究了预热评估以涵盖技术问题。有限元方法用于使用 DEFORM-3D 商业包的 FFSW 模拟。AA5456 的优化工艺参数为销转速为 800 rpm，插入速度为 50 mm/min，锥角为 8° 的类似材料 (AA5456) 销。