Commercially pure aluminum with random texture was prestrained either by rolling or by uniaxial compression, and then tested in uniaxial tension to study the transients in flow stress, work hardening and r-value induced by the strain-path change. New experimental results are reported on the variation of the r-value and the permanently reduced work hardening subsequent to the strain-path change. A continuum plasticity model was developed that can reproduce the observed behavior. The model applies a second-order "delayed pointer" tensor to represent the microstructural anisotropy and was implemented into the finite element software LS-DYNA. The model was calibrated to the experimental data, and a simulation of early strain localization subsequent to an orthogonal strain-path change was compared to strain fields measured by a digital image correlation technique.2

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AlMn alloys are often used for the production of automotive heat exchanger ns. During brazing at about 600• C, recrystallization and grain coarsening resulting in the reduction of the strength and possible buckling of the n can occur. In order to obtain a good recrystallization resistance, the alloy should contain a dense and homogeneous distribution of second phase particles. The eect of Si and Fe addition on the recrystallization response of AlMnZr alloys direct-chill cast in the laboratory conditions and twin-roll cast in the industrial conditions was examined. Microstructure of the alloys was characterized during downstream processing. The particles were analyzed by light metallography, energy dispersive X-ray spectroscopy and by means of electron backscattering diraction. Computer assisted quantitative particle analysis was carried out on eld emission gunscanning electron microscope micrographs. Vickers hardness and electrical conductivity were measured at thicker sheets, while at the nal gauge of 65 µm the 0.2% proof stress was evaluated. The best recrystallization resistance had twin-roll cast alloy containing 0.5 wt% Si and 0.2 wt% Fe.