Mechanical property evolution of ZE10A alloy subjected to thermomechanical treatments between 250 and 300 °C

Magnesium alloys containing rare earth elements have been developed to improve ductility and reduce anisotropy. The ZE10A alloy (Elektron® 717) has demonstrated good performance in hot stamping applications. However, the formability of sheets made from this alloy at temperatures below 350 °C remains insufficiently studied. This work aims to investigate the relationship between thermomechanical treatments in the temperature range of 250–300 °C and the resulting mechanical properties and microstructural evolution of the ZE10A alloy. Uniaxial tensile tests were carried out at 250 °C, 275 °C, and 300 °C at a strain rate of 0.26 s -1 to evaluate the yield strength, ultimate tensile strength, and elongation. The microstructure of the specimens was analyzed by optical microscopy, including average grain size measurements, and by complementary X-ray diffraction (XRD). The results showed that, as the temperature increased from 250 °C to 300 °C, the yield strength decreased by 11.7%, the ultimate tensile strength by 15.7%, and the elongation by 2.7%. Microstructural analysis revealed a transition from slightly elongated grains at 250 °C to partially equiaxed grains at 300 °C, consistent with incipient dynamic recrystallization (DRX). The average grain size decreased from 14.19 μm at 250 °C to 12.61 μm at 300 °C, suggesting the onset of DRX, although its extent may be limited by the presence of neodymium. XRD indicated that ZE10A behaves as a nearly single-phase material within this temperature window (all detectable peaks from α-Mg), with no clear evidence of Mg–Nd precipitates; a slight attenuation of {10–12} twin-related reflections with temperature suggests twin relaxation and recovery/incipient DRX. These findings clarify deformation accommodation in ZE10A at 250–300 °C and support the feasibility of processing in this low-temperature window with a balanced trade-off between strength retention and formability.