Friction stir welding characteristics of 2219-T6 aluminum alloy assisted by external non-rotational shoulder

• Published in: International journal of advanced manufacturing technology 2013-02, Vol.64 (9-12), p.1685-1694
• Main Authors: Liu, H. J., Li, J. Q., Duan, W. J.
• Format: Article
• Language: English
• Subjects: Aluminum alloys; Aluminum base alloys; CAE) and Design; Computer-Aided Engineering (CAD; Deformation; Diamond pyramid hardness; Engineering; Friction stir welding; Industrial and Production Engineering; Inhomogeneity; Mechanical Engineering; Mechanical properties; Media Management; Microstructure; Original Article
• ISSN: 0268-3768; 1433-3015
• DOI: 10.1007/s00170-012-4132-1

Friction stir welding (FSW) of 2219-T6 aluminum alloy assisted by external non-rotational shoulder was carried out, and effects of the welding speed on microstructures and mechanical properties were investigated in detail. Defect-free joints were obtained in a wide range of welding speeds from 50 to 300 mm/min. The microstructural deformation and weld formation were dominated by the rotating tool pin and subsize concave shoulder but the non-rotational shoulder exerted very little effects for all joints. Compared with the weld obtained by conventional FSW, less intense stirring effects in FSW assisted by external non-rotational shoulder can only generate a narrower thermomechanically affected zone, whose width decreased with increasing of the welding speed. Microstructures and Vickers hardness distributions showed that this new welding process is beneficial to improving the asymmetry and inhomogeneity, especially in the weld nugget zone. The maximum tensile strength was up to 69 % of the base material.