Micro/Nano-Structural Transition and Hydrogen Absorption Mechanism in Mg/Cu Super-Laminate Composites

Abstract

The micro/nano-structural transition and hydrogen absorption mechanism in Mg/Cu super-laminate composites (SLCs) were investigated. Differential scanning calorimetry (DSC) measurements were performed on Mg/Cu SLCs at several heating rate and till several repetition cycles up to twenty cycles, and micro/nano-structures of Mg/Cu SLCs were examined by stereomicroscope, digital-microscope, scanning electron microscope (SEM), and scanning transmission electron microscope (STEM). It is found that the micro/nano-stractures of Mg/Cu SLCs change drastically at early cycles and reach a steady state after around the tenth cycle. The detailed examination of DSC curves, and SEM and STEM observations of Mg/Cu SLCs suggest that the hydrogen absorption process consists of a fast and a slow reaction which shows a sharp exothermic peak around at 610 K and a broad exothermic peak around at 570 K connected with it in DSC profiles, respectively.