ABSTRACT The peen forming process is commonly used in the aeronautical industry to form large wing skin panels. This process presents many advantages in terms of cost, production time, and beneficial induced residual stresses. Setting the accurate process parameters to form a given pattern requires however a certain experience and sometimes many trials and errors. The authors propose to model the shot peening induced deformations by elastically equilibrating the real plastic strain gradient present in the whole structure. A complete numerical and experimental protocol is proposed to determine the plastic strain gradient assuming the knowledge of some experimental data. The proposed approach consists in determining the plastic strain field by inverse calculation based on experimentally measured residual stresses fields. A second approach is based on the inverse calculation of shot peening induced plastic strains knowing the global deformation of the treated sheet. A comparison between the proposed approaches applied to partially treated sheets is presented along with experimental data. The numerical results are in good agreement with experimental data and show the strong influence of the peening path on the resulting global deformations of the treated samples
