Magnesium alloy is the lightest metal among structural metals being used today. However, because the rolled sheets of magnesium alloy are expensive and poor in press formability, the reduction of manufacturing costs and especially the improvement of formability are eagerly required. In order to overcome these problems, the dispersion of texture of rolled sheets caused by twin formation in repetitive bending at room temperature would be effective. In present experiment using the rolled sheets of AZ61 magnesium alloy, the relationship between the times of repetitive bending and the change of texture was investigated. In 4-times repetitive bending, the tensile twin formation and the dispersion of basal plane texture were observed by X-ray diffraction and SEM-EBSD analysis. As the result of formability test, severe 90°V shape bending R/tϭ1 and nearly twice bulging formability were attained in comparison with those of conventional rolled sheets at 473 K. The results of this study suggest that the press formability of rolled sheets of AZ61 magnesium alloy would be effectively improved by repetitive bending at room temperature.

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