Effect of Prior Recovery Treatment on the Evolution of Cube Texture During Annealing of Severely Warm-Rolled Al-2.5 wt pctMg Alloy

Abstract

The effect of prior recovery on the evolution of cube texture ({001}〈100〉) in severely warm-rolled and annealed Al-2.5 wt pctMg alloy was studied. The Al-2.5 wt pctMg alloy was warm rolled to 97 pct reduction in thickness at 473 K (200 °C). The warm-rolled sheets were isochronally annealed for 1 hour at temperatures ranging from 523 K to 673 K (250 °C to 400 °C) without and with prior recovery treatments. In case of prior recovery, the sheets were pre-treated at 473 K (200 °C) for different time intervals ranging from 3.6 × 10³ seconds (1 hour) to 8.64 × 10⁴ seconds (24 hours) before the annealing. The warm-rolled alloy showed finely subdivided lamellar structure and strong presence of pure metal type texture. The annealed materials without any prior recovery treatment showed strong cube texture after annealing which could be attributed to the oriented nucleation of cube grains resulting from the preferentially recovered structure of cube regions in the warm-rolled state. In contrast, the cube texture was significantly weakened in materials subjected to different prior recovery treatments. The prior recovery treatments resulted in homogenous recovery which was confirmed by microstructural, textural, and conductivity measurements. Homogenous recovery eliminated the nucleation advantage of cube regions originating from the preferentially recovered structure and weakened the cube texture significantly. The present results indicated that prior recovery treatment could be effectively used to control recrystallization cube texture in severely warm-rolled aluminum alloys.