Microstructure and tensile properties of a commercial 5052 aluminum alloy processed by equal channel angular extrusion

A commercial 5052 aluminum alloy was processed by equal channel angular extrusion at 423 K to a strain of ∼8. The as-extruded microstructure is quite uniform, which can be characterized as a mixture of elongated and equiaxed subgrains with submicrometer size and high misorientations. In static annealing, the as-extruded structure is quite stable at 423 K and shows slow coarsening at 473 K. The microstructure resulted from more ECAE passes (higher strain) is more readily to develop a uniform structure of equiaxed grains in static annealing. Very high strength (394 MPa yield stress and 421 MPa ultimate tensile strength) and reasonable ductility (10.5% tensile elongation) can be obtained in this non-heat treatable aluminum alloy. The high strength can be related to the structure of submicron-sized subgrains (grains). To increase the strain from 4 to 8 is beneficial for producing finer structure and higher strength.