The Influence of Bauschinger Effect in Straightening Process

Abstract

The yield stress changes during the straightening process, because of the Bauschinger effect. This effect leads to a different reduction rate in each straightening roller. To accurately estimate the straightening effect of the rolled piece, the Bauschinger effect must be considered in calculating the reduction rate. In this paper, the straightening model is described by the fast multipole boundary element method. The Bauschinger effect model is discussed in the elastic loading region and elastic plastic loading region. Young’s modulus reduction and the reverse yield stress reduction are obtained for the straightening force model. The straightening force formula including the Bauschinger effect is determined by analyzing the tension and compression processes. This formula reflects the changes of the yield stress and the straightening force in the tension and compression processes. It is concluded that the Bauschinger effect is a very important factor for the precise estimation of the straightening force.