Improving the room-temperature formability of Mg-3Al-1Zn alloy sheet by introducing an orthogonal four-peak texture

Abstract Wrought magnesium alloy sheets suffered extrusion or rolling usually exhibit strong basal texture, which greatly degrades their mechanical performance, and thus, restrict their applications. In this study, a novel texture modification process based on employing in-plane precompression, prestretching and annealing was carried out on an extruded Mg-3Al-1Zn (AZ31) sheet to introduce an orthogonal four-peak distribution of basal texture. The results indicated that such an orthogonal four-peak texture could provide larger and more balanced Schmid factors for basal slip compared with that of the as-extruded sheet when the sheets subject to tension along different directions. As expected, the tensile yield strength was decreased and the ductility was increased effectively, suggesting a considerable improvement in uniaxial deformation ability. Additionally, the orthogonal four-peak texture could also provide more balanced mechanical properties along different directions and contribute to reducing the planar anisotropy. Erichsen tests showed that the Erichsen value of the sample with orthogonal four-peak texture increased up to ∼115% compared with that of the as-extruded sheet. This finding indicated that such a texture modification method was also highly conducive to enhancing the multiaxial stretch formability of the Mg sheets. The orthogonal four-peak texture modification was confirmed as an efficient way to improve the comprehensive mechanical performance of the Mg alloy sheets.