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The influences of aging time and aging temperature on the microstructure and mechanical properties are investigated on the 6005A aluminum alloy extrusions.Artificial aging is performed on the alloy extrusions.The aging times are 4, 8 and 12 h, and the aging temperatures are 150, 175 and 200 ℃ during the aging.The results show that the morphologies of the coarse Al(Fe, Cr)Si precipitates in the aged microstructures are evolved from granular to rodlike particles with increase of the aging temperature or the aging time.The volume fraction of the submicron precipitates reaches the maximum value at the aging temperature of 175 ℃.(AlFeSi) particles in size of 1-3 μm are formed at the grain boundaries at the aging temperature of 200 ℃.Room temperature mechanical properties of the extrusions are more sensitive to the aging temperature than to the aging time.The optimum and stable mechanical properties are achieved when the ageing procedure 175 ℃℃/4-8 h has been performed on the extrusions.The tensile strength and the yield strength in the longitudinal direction of the aged extrusions are more than 300 MPa and 270 MPa, respectively.