Influence of forming parameters on static recrystallization behaviour during hot rolling aluminium alloy 5083

In this paper, the influence of rolling parameters (i.e. rolling temperature, roll speed, roll temperature, friction and the ratio of the mean thickness to the contact length in the roll gap H-m/L) on static recrystallization (SRX) behaviour is studied by the combination of the finite element method (FEM) with the Taguchi experimental method. The FEM is first applied to simulate a single pass laboratory rolling experiment by the use of both empirical and physical models. A new approach is used to generate the mean value of the Zener-Hollomon parameter, which is necessary for the prediction of the volume fraction recrystallized (X-V) when the empirical SRX model is used. A physical model which considers the density of recrystallization nuclei and the total stored energy is also applied based on the prediction of internal dislocation density, subgrain size and misorientation. The predicted X-V and the recrystallized grain size at the centre and subsurface fit well with experimental measurements from the literature. Then, the Taguchi method is applied to design an orthogonal experimental table, L9(3(4)), which indicates that there are four parameters, each parameter has three levels and a total of nine test runs need to be conducted. These nine virtual experiments are analysed by the use of FEM. The predicted results are then analysed by the use of the Taguchi method from which the influence of each rolling parameter on X-V is given. The studies show that rolling temperature has the greatest influence on X-V for the centre point whilst friction is the most important parameter on the determination of X-V within the surface region. The roll temperature and roll speed have little influence on X-V for both the centre and subsurface point.