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Introducing {10-12} tension twin lamellas has proved to be the most effective strategy to enhance the performance of Mg alloys. Twins can provide the preferential nucleation sites for recrystallization, hence twinning induced grain refinement can result in higher strength material based on Hall-Petch Effect. In addition, twinning can also modify the crystallographic c-axis distribution in wrought Mg alloys resulting in lower plastic anisotropy. Accordingly, in the present work, the twinning evolution in the Mg-0.5Ca (wt.%) alloy at room and cryogenic temperature was critically investigated. The samples were subjected to pre-compression (5%) at room temperature and -150 °C at the strain rate of 10-3 s-1. The microstructural and textural characterization was carried out using OM, SEM and EBSD to emphasize the twinning evolution during compression at room and low temperatures. The local lattice distortion and the localized deformation in terms of Kernel average misorientation (KAM) was also studied. The results revealed the significant grain refinement (13.7 μm 5.61 μm and 6.02 μm of uncompressed and RT, - 150 °C pre-compressed, respectively), where slightly enhanced twinning fraction in the sample compressed at RT was observed. Finally, remarkable increase in the yield strength was noticed in the pre-twinned samples, which was attributed to the twinning-induced grain refinement based on the Hall-Petch relationship.

The austenitic stainless steel's remarkable mechanical properties are caused by twinning‐induced plasticity and transformation‐induced plasticity mechanisms. Numerous studies focus on stacking fault energy's effect, which is affected by various factors, to interpret and control these mechanisms. However, crystallographic orientation is also an important parameter for mechanical properties in metals. This study compares the mechanical properties and microstructural features of 304 austenitic stainless steel, focusing on the effect of initial texture and deformation temperature. Microstructural characterization is identified by an interrupted tensile test based on strain, tensile direction, and temperature conditions, and X‐ray diffraction and electron back‐scattered diffraction analysis are performed. The results show that the mechanical features and strain‐induced martensitic transformation rate depend on the tensile directions. In addition, this trend is maintained irrespective of the temperature conditions. The attribute reason is that the difference in the Taylor factor and the formation rate of the deformed band structure is induced by the initial crystallographic orientations. Moreover, a decrease in temperature significantly increases the dislocation densities and abundant twins and transformed martensites formation. Furthermore, the yield and tensile strengths are enhanced while the elongation decreased with the tensile strains.