7 A85 aluminum alloy ingots were prepared by semi-continuous casting process

and extruded strip plate with section size of 50 mm×300 mm was prepared by extrusion process

followed with solution treatment

10%cold compression treatment and artificial aging treatment at 120 ℃.The effects of 10% cold deformation on the aging microstructure of 7A85 aluminum alloy were investigated by means of TEM and room temperature testing.The results indicate that after solution treatment

a large number of dislocations are induced by 10% cold deformation treatment

thus improving the strength of the alloy.At the initial stage of aging

the amounts of precipitates in the 7A85 alloy with 10% cold deformation treatment is significantly higher than that of ones without cold deformation treatment

which plays a certain role in pre-aging.At the end of aging

the amounts of precipitates and dislocations in 7A85 aluminum alloy treated by 10% cold deformation are higher than that of ones without cold deformation treatment

leading to the enhancement of tensile strength and yield strength as well as reduction of the elongation.