Springback analysis in sheet metal forming by using the Ramberg–Osgood stress-strain relation

The Ramberg–Osgood stress-strain relation is used to perform a theoretical springback analysis in the problem of bending of a narrow rectangular strip made of a strain-hardening material. The maximum strip thickness is 5 mm, and its length is significantly greater than the thickness. Based on the elasticity and plasticity deformation theory and also on the Tresca and von Mises yield criteria, an expression for the springback ratio is derived. The springback ratio depends on the ratio of the yield stress to Young's modulus, Poisson's ratio, strain hardening coefficient, and sheet thickness.