Al–Mg–Si系合金の集合組織形成に及ぼす中間焼なましおよび冷間圧延率の影響*

抄録

The effects of precipitation and cold-rolling reduction on recrystallization textures of an Al–Mg–Si alloy were investigated. The sample sheets were prepared by solution heat treatment followed by intermediate annealing (IA) at 623 K for 1 h (IA-1 h) or 110 h (IA-110 h). Other sheets were prepared without IA (non-IA). These samples were rolled at ambient temperature up to 97.5% reduction followed by a final annealing step at 623 K. The recrystallization textures changed depending on the IA conditions. In the IA-1 h sample, the cube texture ({001}〈100〉) increased with increasing reduction. In contrast, in the non-IA sample and IA-110 h sample, the cube texture decreased at high rolling reduction. Shear bands were formed in the cold-rolled non-IA sample. Shear bands could be the nucleation sites of randomly oriented grains in the recrystallization process. Meanwhile, in the IA-110 h sample, the particle stimulated nucleations (PSN) of recrystallized grains by coarse precipitates were observed. Grains generated by PSN are expected to be randomly oriented. Therefore, the nucleation at shear bands and PSN cause a decrease in the cube texture. In addition, decreasing of the cube texture at high reduction is assumed to be caused by increasing of shear bands and deformation zones around coarse precipitates.