Welding Deformation and Residual Stress of Aluminum Alloy Sheets Welded by Friction Stir Welding at Super High Rotation Speed

The 100 mm×80 mm×1 mm 2014 aluminum alloy sheets were butt welded by the friction stir welding equipment at super high rotation speed of over 10 000 r·min^-1. The deformation of aluminum alloy sheets was controlled by the water mist cooling method, and the weldments with good appearance and small deformation were obtained. The welding deformation and the residual stress of the weldments were measured and analyzed. The results show that:there was no thinning of welding seam of the 2014 aluminum alloy sheet; the minimum transversal deflection was 0.25 mm, and the minimum longitudinal deflection was 0.3 mm; the residual stress of the welding seam was very low, and the peak value interval of longitudinal residual stress was from -43 MPa to -83 MPa.