Understanding room-temperature deformation behavior in a dilute Mg–1.52Zn–0.09Ca (mass%) alloy sheet with weak basal texture

Abstract

The deformation behavior of a weakly textured Mg–1.52Zn–0.09Ca (mass%) alloy sheet during room-temperature uniaxial tensile and bending tests was thoroughly investigated using the electron backscattered diffraction technique and crystal plasticity finite-element method. The sheet exhibited a high elongation to failure of 46.1% along the transverse direction because of the easy activation of basal slips, prismatic slips, and tensile twinning. Although the activities of the basal slips and tensile twinning were suppressed during the tensile deformation along the rolling direction, the sheet showed a satisfactory elongation to failure of 28.2% owing to the activation of the prismatic slips. Notably, the sheet exhibited excellent stretchability with a limiting dome height of 10.1 mm. This was attributed to a small fraction of the basal texture component, which facilitated the basal slips during the stretch formation. However, during the bending deformation, the prismatic slips and tensile twinning became less active than during the uniaxial tension, affording inferior bendability to that of automotive-grade Al alloy sheets. This may help to establish microstructural design guidance for the development of room-temperature formable Mg alloy sheets.