Residual Stresses in Elastoplastic Bending of Round Bar

Abstract

Elastoplastic deformation on the presses and high-temperature heating of the steel sheet cause the large residual stresses in the sheet’s and bar’s wall. The technological operations of the obtaining of metal products, their shape and linear dimensions strongly affect on the distribution within the metal and the maximum values of residual stresses. The uneven cooling of various parts of the sheet and bar, obtained by bending, stamping and forging, also leads to the large residual stresses inside the metal. The greatest residual stresses occur in the weld area, where there is a strong heterogeneity of mechanical and physical properties of the metal due to uneven heating and cooling. Below the new analytical method for calculating of the residual stresses of a round steel bar in the elastoplastic bending is obtained. This method takes into account the diameter of the bar, as well as the modulus of elasticity, the yield strength and the hardening modulus of steel’s bar.