Furukawa-Sky Review No.8 (April 2012)

技術論文

Evolution of Recrystallization Texture in Aluminum Alloy Sheets by Asymmetric-Warm-Rolling

Yoshikazu Suzuki
Osamu Noguchi
Yoshiki Miki
Yoichi Ueno
Katsumi Koyama
Toshio Komatsubara

Asymmetric-warm-rolling (AWR) is a promising process to improve the Lankford value (r-value) or the deep drawability of aluminum alloy sheets by controlling the crystallographic texture of the alloy. A fundamental study has been conducted on the formation of a distinctive recrystallization texture in the Al–1 mass% Si–0.6 mass% Mg (AA6022) alloy sheets prepared by AWR at 523K. The change in texture during the recrystallization process was observed by using a SEM-EBSD system with a heating stage. The as-AWRed sheets have a considerably recovered subgrain-structure with a major orientation of {001}<110> and texture fibers of <011>//RD and near <111>//ND. Some of the recovered grains act as the nuclei for the recrystallization process and grow consuming adjacent grains. The area fraction of the <001>//ND grains decreases with grain growth during the multistep- annealing at 573-723K. The {112}, {332} and {221} grains increase or remain high in area fraction during the annealing, whereas the fraction of the ideal {111} grains decreases. For the T4 sheets made by AWR, not only the ideal {111}, but the slightly rotated components probably contribute to a high average r-value. Limited area fraction of {001} grains is another reason for the high r-value.

技術論文

Evolution of Recrystallization Texture in Aluminum Alloy Sheets by Asymmetric-Warm-Rolling

技術論文 / Technology Articles