Papers by Author: Menno van der Winden

Abstract: A mathematical model has been developed and validated to predict deformation, temperature and microstructure evolution during multi-pass hot rolling of an AA5083 aluminum alloy. The validated model was employed to examine the effect of changing the number of rolling passes and the strain partitioning during multi-pass rolling on the material stored energy and the resulting microstructure. Results indicate that the number of rolling passes has a significant effect on the material stored energy. In addition, the way the strain is partitioned in two-pass rolling cases affects the material stored energy with decreasing strain/pass providing the highest stored energy in the material after rolling and vice versa. The reason behind these results was further investigated indicating that the thermal evolution during rolling may significantly influence the material stored energy and subsequent recrystallization kinetics.

Abstract: One of the challenges for the Aluminium industry is to reduce the costs and lead times of the development of novel alloys. This can be achieved by applying increasingly sophisticated models to predict the microstructures and properties of novel chemistries and processing routes. At Corus RD&T, several physically based microstructure models and one process model have been developed and integrated into a Through Process Model (TPM). The TPM presented here is constructed from microstructural sub-models that predict precipitation, work-hardening, recovery and recrystallisation. Furthermore, there is a finite difference based process model that predicts the local process variables like strain, strain rate and temperature. The final sub-model translates the predicted microstructures into product properties. In this paper the integrated model has been applied to the production chain of brazing sheet (AA3103) covering all steps from homogenisation to the braze cycle as applied by the manufacturers of for instance heat exchangers. The model predictions have been verified by comparing them to the results of full-scale a plant trial. Microstructure and mechanical properties were experimentally characterized and predicted at various production steps. Due to the limited space, here, only the results of the through process modelling on microchemistry are presented. Nevertheless it can be concluded that the (fully predictive) results of the models compare well with those found experimentally which opens up the option to use such models for alloy development.