The effect of high-pressure torsion on the microstructure and hydrogen absorption kinetics of ball-milled Mg70Ni30

Ball-milled nanocrystalline Mg70Ni30 powders were subjected to heavy shear deformation by the process of high-pressure torsion (HPT). X-ray diffraction analysis revealed that HPT results in a deformation-dependent microstructural refinement. Complementary hydrogen sorption kinetic measurements indicate that the maximum absorption capacity is increased by 30-50% after HPT due to the creation of new possible hydrogen absorption sites at the grain boundaries and at lattice defects. (C) 2010 Elsevier B.V. All rights reserved.