The microstructure and texture evolution of AA8021 aluminum foil during annealing at 270 C with heating rates of 10 C h⁻¹ and 40 C h⁻¹ were investigated by the optical microscope (OM), microhardness tester, field emission scanning electron microscope (FE-SEM) and x-ray diffractometer (XRD). The results show that the microhardness of aluminum foil gradually decreases during the heating process, and the microhardness of aluminum foil with the heating rate of 40 C h⁻¹ is higher than that of 10 C h⁻¹. After annealing at 270 C for 16 h, the average grain size of aluminum foil with the heating rate of 10 C h⁻¹ is 13.0 μm and the maximum grain size does not exceed 35 μm, while the average grain size with the heating rate of 40 C h⁻¹ is 14.6 μm and its fraction of the grain area of greater than or equal to 40 μm is 2.4%. The slow heating rate is beneficial to grain refinement of AA8021 aluminum foil due to the release of most deformation energy in the low temperature stage during heating, which leads to the decrease of driving force for crystal nuclei growth. Under the two heating rates, the texture components of the material after annealing are basically the same, mainly the recrystallized Cube, R textures and the residual rolling textures.

在270℃与10℃h加热速率退火期间AA8021铝箔的微观结构和组织演化^-1和40℃ħ ^-1是由光学显微镜（OM），显微硬度计，场发射扫描电子显微镜（FE-调查SEM) 和 X 射线衍射仪 (XRD)。结果表明，铝箔的显微硬度在加热过程中逐渐降低，40 Ch h ^-1加热速率的铝箔显微硬度高于10 Ch h ^-1的显微硬度。270 C退火16 h后，加热速率为10 C h ^{-1 的}铝箔平均晶粒尺寸为13.0 μ m，最大晶粒尺寸不超过35 μm，而加热速率为40 C h ^-1时的平均晶粒尺寸为14.6 μ m，大于或等于40 μ m的晶粒面积的比例为2.4%。缓慢的加热速率有利于AA8021铝箔的晶粒细化，因为在加热过程中的低温阶段释放了大部分变形能，导致晶核生长的驱动力降低。在两种加热速率下，材料退火后的织构成分基本相同，主要是再结晶的Cube、R织构和残余轧制织构。