The ordered orientation gradient “sandwich” texture induced high strength-ductility in AZ31 magnesium alloy

A novelty ordered orientation gradient “sandwich” texture was fabricated in low-alloying Mg-3Al-1 Zn alloys using low cost process which is single-pass rolling and subsequent annealing (SPR+A) to realize a high strength-ductility combination with yield strength (190.5 MPa), ultimate tensile strength (291.5 MPa) and elongation (26.5%). The high strength is related to the combination effect of fine grain strengthening and orientation strengthening at the top and bottom position of the alloy. This attributes to the fact that the soft-orientated grain embedding hard-orientated grain structure restricts the deformation of soft-orientated grain, substantial basal-prismatic slip (B-P) modes increase the activation stress for intergranular accommodation, and high fraction of fine grains causes the fine grain strengthening. The high ductility is resulting from the “sandwich” texture structure, beneficial for crack deflection and an ordered orientation gradient texture at the middle position (coarse grain area), effectively introducing non-basal slip and providing enough dislocation motion space. [Display omitted]