Aluminum alloys are widely used in aerospace, transportation, and many other fields due to their excellent properties such as lightweight, ultra-strength, and high toughness. This paper analyzed the influence mechanism of friction stir on the microstructure, texture, and mechanical properties to realize the strength and toughness of 7055 aluminum alloys and optimize their deformation process. The results show that the aluminum alloys change from uneven banded grains to uniform and fine equiaxed grains after friction stir processing, and the grain size is refined from 14 μm to 0.71 μm. The high-angle grain boundary and texture intensity present an initial increase but a subsequent decrease due to the combined effect of recrystallization and high-temperature softening caused by the heat input of friction stir processing. The total texture intensity and volume fraction of the friction stir processed aluminum alloys decrease significantly, and the intensity of RtG {110} <110>, A {110} <111>, E {110} <111>, and F {111} <112> texture significantly decrease or disappear, while the Brass (B) {110} <112> texture increases. The yield strength of FSP aluminum alloys decreases with increasing heat input (w/v), which mainly depends on the weakening of the texture strengthening effect. However, the increase of geometrically necessary dislocations (GND) caused by grain boundary sliding leads to the significant improvement of the deformation hardening ability and plasticity of the material. In addition, the effect of texture on the plasticity of aluminum alloys was calculated by using Schmid law. It is found that the equivalent slip factor (ESF) and maximum Schmid factor (μmax) of A, E, and Cu textures are equal to 0. The small ESF and μmax of the S texture are not conducive to the plastic deformation property of materials, while the 1000 × 70 sample with more ESF (8) and μmax (0.41) of the Cube texture ({001} <100>) shows better plasticity.
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