Anisotropy of Bending Properties in Industrial Heat-Treatable Extruded Aluminium Alloys
In the present work, three-point bending tests have been performed on four commercially extruded 6xxx- and 7xxx alloys, one with a fibrous and one with a recrystallized grain-structure for each alloy class, with the bending axis orientated 0, 45 and 90° with respect to the extrusion direction. Microstructure and texture characterization as well as tensile testing of the same materials have been performed and correlated with the bending results. In general there is good agreement between the bending angle and the fracture strain for all alloys, with the highest values in the extrusion direction. However, there are no indications in the microstructure and texture that explain the large differences in bendability observed. Die lines and recrystallized layer on a fibrous alloy have been removed to investigate their effect on the bending behaviour. However, these effects also seem to be limited, and cannot explain the anisotropy effects observed in bending angles.
T. Chandra, N. Wanderka, W. Reimers , M. Ionescu
K. E. Snilsberg et al., "Anisotropy of Bending Properties in Industrial Heat-Treatable Extruded Aluminium Alloys", Materials Science Forum, Vols. 638-642, pp. 487-492, 2010