Residual stress induced convex bending in laser peen formed aluminum alloy

Laser peen forming is a purely mechanical forming method developed to accurately bend, shape, precision align, or repair components using nanosecond-pulsed laser induced shock waves. This paper aims to clarify the residual stress induced bending process in laser peen formed aluminum alloy plates. Finite element simulations were performed to investigate the bending angle and residual stress redistribution before and after bending. A reasonable agreement between simulation and experiment results was achieved. The results showed that larger bending angle was obtained by increasing the number of laser impacts and laser peened area. Besides, the bending angle in 3 mm plates was larger than that in 2 mm plates under the same processing condition. The laser peening induced bending angle is controlled by a residual stress gradient in the thickness direction.