Effect of Solution and Aging Treatment on Microstructure and Properties of Pressure Formed 6063 Aluminum Alloy

6063 aluminum alloy was prepared by pressure forming process, and then was treated by solution at 535 ℃ and aging. The effects of solution time (15-120 min), aging temperature (160-200 ℃) and aging time (1-24 h) on the microstructure, tensile properties and hardness of the aluminum alloy were studied. The results show that with increasing solution time, the grain size of 6063 aluminum alloy increased, and the primary Mg₂Si phase gradually disappeard and redissolved in the matrix; but the solution time had no effect on the content and morphology of α-Al₈Fe₂Si phase and β-Al₅FeSi phase. After solution treatment, with increasing aging temperature or aging time, the number of second phase Mg₂Si increased, but a higher temperature or a longer aging time resulted in the coarse of the Mg₂Si phase. With increasing solution time, aging time or aging temperature, the strength and hardness of the alloy increased first and then decreased, and the precentage elongation after fracture decreased first and then increased. The appropriate solution and aging treatment system for 6063 aluminum alloy was 535 ℃×60 min + 180 ℃×7 h; at this time the Mg₂Si phase precipitated in the alloy was the smallest and dispersed, and the alloy had the highest strength and hardness and the appropriate precentage elongation after fracture.