[en] Full text: Due to the low density and high gravimetric capacity of hydrogen, magnesium and its alloys are interesting materials for the safe and effective storage of hydrogen in the solid state [1]. Other factors contribute to the improvement of its properties, such as grain structure refinement and adequate crystallographic texture, which can potentially be obtained by channel angular pressure equivalent to selected processing parameters [2], [3]. Pure magnesium was ECAPed to 1 to 10 passes, Bc route at 300 °C. The microstructure, texture (X-ray diffraction (XRD) and Electron Backscattered Diffraction (EBSD) and hydrogen storage properties were observed. The initial microstructure has grains with sizes from 16 to 0.2 mm. In the first 5 passes the grain size became more homogeneous (82 μm ±15) but after the 6^th pass an increase (150 μm ±20) was observed due to dynamic recrystallization. The XRD texture of the 1^st pass had basal fiber (0002) aligned with the extrusion direction, and intense component (11-11) <11-20>. With the increase of the passes, the basal fiber disintegrated, originating prismatic and pyramidal fibers. EBSD confirmed the presence of dynamic recrystallization. Hydrogenation on ECAPed bulk samples did not absorption because of the large thickness, grain size and non ideal texture. Therefore, the ECAPed samples were filled to produce a higher specific surface area. This resulted in a significant improvement in both the amount of absorbed hydrogen and the kinetics of absorption and desorption, showing that materials with high surface area and small thickness also have improved hydrogenation properties. References: [1] Züttel, A., Materials Today, 6, 24-33 (2003) [2] Zaluska, A.; et al., Journal of Alloys and Compounds, 288, 217-225 (1998) [3] Jorge Jr., A. M.; et al., International Journal of Hydrogen Energy, 39, 3810-3821 (2014). (author)