The deformation at 0.039 true strain resulted in enhanced mechanical {10-12} twinning (Fig. 3c). Lenticular-shaped twins formed several parallel boundaries inside the parent grain. They can be easily distinguished by the red colour, which denotes that c axes of crystallite is parallel to extrusion axis. Contrary to deformation of 0.002 true strain, the tensile 10-12 twinning undergoes Schmid law, preferring the variants with the highest SF