Thermo-mechanical simulation of a rolling process with an FEM approach

The authors propose a model for the study of a hot rolling process, and the approach is based on thermo-mechanical analysis using the Finite-Element Method (FEM). The model can be used to speed up and improve the design and evaluation of the roughing and finishing phases in plate and sheet production. It is able to calculate the temperature distribution in the roll and the plate, the stress and strain fields, throughout a transient analysis done starting from the first phases of the process. The main hypotheses adopted in the formulation are: the elasto-plastic behaviour of the material; and rolling under plane-deformation conditions. The main variables that characterise the rolling process, such as the geometry of the plate and the roll, the loads and the boundary conditions (radius of the rolls, rolling speed, initial and final thickness, initial temperatures of the plate and the roll), have been expressed in a parametric form, this approach giving a good flexibility to the model. During the simulation, an iterative procedure enables the calculation and updating of the load conditions, such as the heat produced by friction on the plate-roll contact arc, and that caused by plastic deformation. The congruence of the results has been evaluated using experimental and theoretical data available in the literature.