Modelling of the cooling and thermal treatment of bimetallic rolling mill rolls

Abstract

This work is focused on the modelling of post casting cooling and heat treatment stages, using a coupled thermo-mechanical metallurgical model in order to understand the behavior of bimetallic rolling mill rolls. The case of interest is a bimetallic rolling mill roll which materials and geometry present a risk of failure in industrial manufacturing. The analysis of residual stress fields together with a rough damage approach allows the understanding of the failure event and predicting trends when industrial conditions are modified. Performed finite element modelling requires a complete set of materials parameters. Experimental and numerical methods are applied in order to obtain thermophysical, mechanical, metallurgical and coupled parameters. Sensitivity analysis is performed in order to evaluate the effect of numerical predictions to different input data, modeling eventual modifications of materials or geometries. Finally, conclusions and perspectives obtained from this research allow establishing some weakness of the implemented model, enhancing the importance of considering more advanced damage models. In addition, it is settled that the material characterization must be improved by considering materials pollution and complexity. However the work provides a convincing explanation of the observed phenomena of ruptures.