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再生高强铝合金由于力学性能差,在结构材料方面的应用有限.喷射成形重熔后再热挤压是一种有前途的用于7系铝合金的再加工方法.对7050铝合金切屑进行喷射成形、热挤压、旋锻和热处理,以恢复其力学性能.制备直径2.7 mm的再生铝合金线材,研究其显微组织、拉伸性能和疲劳强度.采用XRD、SEM、EBSD、TEM和DSC等手段对二次相和析出相进行表征.对比锻态和热处理(固溶和时效处理)态合金线材的力学性能,发现两种合金线材的力学性能均优于AA7050航空规范.材料在旋锻过程中发生大量的塑性变形,从而导致急剧的晶粒细化,可观察到细小的微观和亚微观Al晶粒、粗大和细小的金属间化合物析出相.随后的固溶处理导致形成均匀的再结晶和等轴晶(9μm)显微组织.在120 ℃时效处理后,形成纳米级GP(I)区和η′ 析出相,合金表现出更高的抗拉强度(586 MPa)和疲劳强度(198 MPa).“,”Recycled high-strength aluminum alloys have limited use as structural materials due to poor mechanical properties. Spray forming remelting followed by hot extrusion is a promising route for reprocessing 7xxx alloys. The 7050 alloy machining chips were spray formed, hot extruded, rotary swaged and heat-treated in order to improve mechanical properties. Microstructures, tensile properties and fatigue strength results for a 2.7 mm-diameter recycled wire are presented. Secondary phases and precipitates were investigated by XRD, SEM, EBSD, TEM and DSC. As-swaged and heat-treated (solution and aging) conditions were evaluated. Mechanical properties of both conditions outperformed AA7050 aerospace specification. Substantial grain refinement resulted from the extensive plastic deformation imposed by rotary swaging. Refined micrometric and sub-micrometric Al grains, as well as coarse and fine intermetallic precipitates were observed. Subsequent solution treatment resulted in a homogeneous, recrystallized and equiaxed microstructure with grain size of 9 μm. Nanoscale GP(I) zones and η′ phase precipitates formed after aging at 120 ℃, imparting higher tensile (586 MPa) and fatigue (198 MPa) strengths.