Numerical simulation of stress peen forming with regular indentation

Stress peen forming is widely used to form the thin components with complex shapes in the aerospace industry. The prestress has an influence on the residual stress profiles, thereby influencing the peen forming forces: bending moment and stretching force for shaping the component. A static one-shot FE model was performed to investigate the residual stress profiles of single shot indenting under different prestresses and loads. A static four-shot FE model was performed to investigate the overlapping of the stress fields of adjacent shots indenting. The simulation results reveal that the tensile prestress enhances the indentation diameter and the plastic region size resulting in larger and deeper compressive residual stresses. The average peen forming forces of regular distributed four shots are four times the forming forces of one of shots when the separation distance of adjacent shots is larger than the plastic region size of one shot indenting. Experiments with different prebending arc heights and indenting gaps were carried out on aluminum alloy 2024-T351 strips with a developed Brinell hardness tester. The experimental results validated the simulation results. (C) 2014 Published by Elsevier Ltd.