Abstract:The repetitive continuous extrusion forming process (R-Conform process) was carried out on the pre-aged 6201 Al alloy produced by continuous casting and rolling. The microstructure characteristic and mechanical property evolution of the R-Conform processed alloy were investigated using electron back-scatter diffraction (EBSD), transmission electron microscopy (TEM), X-ray diffractometer, polarizing metallographic microscopy, and tensile testing. The results showed that R-Conform can effectively refine grain size and homogenize alloy microstructure, the average size of the grain was refined from 259μm to 60μm. A large number of β′′ phases have precipitated in the pre-aged 6201 Al alloy. While with the increasing of R-Conform pass numbers, high density of dislocations formed, gradually tangled with each other, and finally transformed to subgrain boundaries; a part of needle β′′ phases dissolved into the Al alloy matrix. With the increasing of R-Conform pass numbers, the balance of strength-ductility( TS× EL) increased from 2.93GPa% to 4.85GPa% after fourth passes and then stabilized. The mechanical property evolution was mainly attributed to the synthetic effect of dislocation increase, grain refinement and the dissolution of β′′ phases.