ABSTRACT
Since 1990 a number of numerical studies on the basis of three-dimensional finite element analysis have been pre sented for predicting the shape of the workpiece during rod and bar rolling. FEA is very effective for computing the ther momechanical state of a workpiece, i.e., the distribution of effective plastic strain, strain rate, and temperature across the section as well as prediction of the surface profile of the exit cross section, but it requires at least half an hour to run a program for a single pass, since three-dimensional analysis is required in nature. Thus considering compu tational time necessary for the number of passes in rod and bar mill and complicated boundary conditions (friction coeffi cient a t the roll/material interface and heat transfer coeffi cients dependent on the temperature and roll pressure), the capability for predicting the exit cross-sectional shape by an analytic model of a simple form with reliable accuracy and a noniterative computational frame has been highly desired if we are interested only in predicting the surface profile at exit.
