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The additive friction stir deposition（AFSD）experiment of 2219 aluminum alloy was conducted under the process parameters of the spindle rotational speed of 250-350 r/min and transverse speed of 50-150 mm/min，the effects of varying process parameters and multilayer thermal cycling on the macroscopic forming of deposited materials，microstructures and mechanical properties were investigated. The results show that well-formed single-pass 16-layer additive specimens can be successfully obtained under the process parameters of the spindle rotational speed of 250 r/min and the traverse speed of 100 mm/min. The grain size in the additive zone undergoes significant refinement，ranging from 4 to 6 μm，and the fine equiaxial crystal organization replaces the coarse irregular grain organization characteristic of the feed rod. The additive specimen undergoes intense dynamic recrystallization，with overall recrystallized grains above 80%，and the bottom of the specimen（the 1st Layer）is subjected to multiple thermal cycles，with recrystallized grains reaching 91.8%. The texture of the additive zone basically consists of four recrystallized textures(Cube，Copper，P and RtB)，as well as S，Brass and T textures. Significant softening of the hardness and tensile strength of the additive specimens occurs. The maximum hardness of the 16th layer is 80HV，which is about 55.6% of the base material of the feed rod，the hardness of the 1st-8th layers is uniformly 60HV. The average tensile strength of Layer 9-16 and 1-8 in the LD（longitudinal direction）direction of the additive zone is 243.0 MPa and 219.3 MPa respectively，which is about 60.0% and 52.9% of the base material，the average elongation is 19.4% and 24.5%，which is about 181.1% and 229.0% of the base material respectively. The fracture modes in the LD direction of the additive specimens are all ductile fracture.