Microstructure and texture of pure magnesium after room-temperature lateral extrusion

Three specimens of pure magnesium with different columnar structure orientations have been subjected to severe plastic deformation (SPD) by lateral extrusion (LE) at room temperature. As a result of the deformation (ε ~ 3.9), 1-mm thick plates were obtained. It is shown that the deformation led to a substantial size reduction of the initial structure by more than two orders of magnitude. The plates have a bimodal structure where large grains of several microns are surrounded with smaller ones of 0.1-0.5 µm. It is expected that the main mechanism of grain size reduction is related to twinning processes along with slip and dynamic recrystallization. All the plates show basis texture of varying degrees of sharpness. Under tensile tests the plasticity of the three plates varies between 8% and 16%.