Weld distortion control in laser welding of T-joint titanium alloy based on multi-point flexible fixture

Titanium alloy T-shape joints are commonly employed in the field of aircraft manufacturing, and its laser welding process is relatively mature. However, even if the heat input in the high-speed laser welding process is already relatively low, there will still be a certain degree of deformation after welding. Due to the high-precision requirements in the aircraft manufacturing, the angular distortion of welded sheets needs to be further reduced, so that additional active control would be necessary to apply to minimize such angular deformation. In this paper, an active deformation control method based on programmable multi-point flexible supports is proposed and verified. For traditional rigid clamping, the preset stress is not suitable in view of the problem of weakly rigid ribbed thin structure. A multi-point flexible support device with micro-controller and linear electrical actuator is designed in this study, which can monitor and adjust the force of the current support position in real time during the welding process. The welding deformation thus could be effectively reduced.