Study on reducing edge effects by using assistant force in laser forming

• A method with various assistant forces is proposed to reduce the edge effect.
• The forming accuracy can be improved under the action of two unequal concentrated forces.
• The relative variation of bending angle ηα decreases by about 80 per cent compared with that of the pure laser forming.
• It is found that the forming accuracy is closely related to the temperature distribution under the constant geometry and material.

The laser forming process, in which a bending deformation of a metal plate is produced by nonuniform thermal stress coming from nonlinear laser-heating cycles, is a promising technology for the rapid production of metallic shaping components. In laser forming, except for the desirable bending deformation, the bending angle varies along the laser-heating line. This undesirable deformation, or edge effect, exists because the forming process is asymmetrical, which leads to the forming accuracy failing to reach the design requirement. To reduce the edge effect, a method with various assistant forces is proposed and the effects of these different forces on forming accuracy have been studied. The results show that the forming accuracy can be improved under the action of two unequal concentrated forces. The relative variation of the value of the bending angle decreases by about 80% compared with that of the pure laser forming when the proper external forces are chosen. The laser process parameters also play an important role in the bending angle variations under constant geometry, material, and assistant forces. The final shapes of a forming part may be controlled to a desirable accuracy by selecting the proper assistant forces and process parameters.