A normalized model is proposed for the characterization of pre-stress state in shot peen forming process

in which the pre-stress of plates undergoing bending shot-peening deformation state is characterized by a pre-stress parameter. Quantitative relations are established between the curvature of shot peened plates and shot peening parameters with the inclusion of the influence of pre-stress state. Pre-stressing shot peen forming experiments were designed and carried out to verify the validity of the normalized model. Results show that quantitative formulations can be established on a normalized pre-stress parameter interval [0

1] for the description of the bending deformation behavior of pre-stress shot peened plates. When certain shot peening parameters are given

the curvature of the shot peened plate in the pre-bending direction is linearly related to the pre-stress parameter

proportional to shot peening pressure

quasi-inversely proportional to peening speed

and inversely proportional to the 3/2 power of the plates of thickness

while all the proportionality coefficients are determined by the pre-stress parameter.