Continuous grain refinement of aluminum strip by conshearing

The ‘conshearing’ process, a continuous version of Equal Channel Angular Extrusion was applied to 2 mm thick 1100 aluminum alloy strips at room temperature. It was found that the optimum flection angle of the ECA die (or the supplementary angle of the channel angle) to impose high strain is 65°. The 〈1 1 1〉//ND shear texture was developed and showed maximum intensity after two passes. After six passes, banded microstructure with ultrafine grains of which mean thickness and length were 0.42 and 1.4 μm, respectively, was observed. The obtained material showed well-balanced mechanical properties; i.e., a tensile strength of 170 MPa and an elongation to failure of 23%.