Synthesis of Mg-C Alloys and Their Hydrogenation Properties

Abstract

  Magnesium based alloys possess light-weight and high hydrogen absorption capacity so that they have been investigated extensively for several decades. Great attention also has recently been paid to graphite as a hydrogen absorber. In this study Mg-C alloys were prepared by ball milling and their hydrogenation properties were investigated. Powders were first mixed with a 1 : 1 molar ratio of Mg to graphite. Milling balls and a pot were made of SUS304. This process was performed with a vibration ball mill at the speed of 11.8 Hz under an Ar gas atmosphere for 60 hours. The prepared powders were handled in a glove box filled with an Ar gas. After ball milling, samples showed a new X-ray diffraction peak, which was either not a peak from Mg and/or graphite. An affinity for the powders with hydrogen was confirmed at 453 K and the 1.8 MPa hydrogen pressure. The total amount of absorbed hydrogen was estimated to be 2.0 wt% from the thermal desorption spectroscopy (TDS) spectrum.