MODELING HOT FLAT-ROLLING OF COMPONENTS HAVING CURVED PROFILES .2. CHARACTERIZATION OF HEAT-TRANSFER AND FLOW-STRESS

To obtain the mean temperature of the workpiece, a temperature sub-mod el is formulated based on one-dimensional transient flow in the roll-b ite and two-dimensional transient flow outside the roll-bite. The mode l is capable of predicting (i) the through-thickness temperature distr ibution in the roll-bite, (ii) the mean temperature of the deforming b ody, and (iii) the approximate mean temperature distribution along the workpiece. The influence of rolling speed and reduction ratio is also investigated. To characterize the high temperature behaviour of steel s, the well-known unified creep relationship is chosen as the flow str ess sub-model. It is shown that reasonably accurate prediction of the flow stress is achieveable, by using experimental data reported in the literature.