Phase transformation rate in hydrogen absorption of magnesium-based materials
(1. Department of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China;
2. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China)
Harbin Institute of Technology, Harbin 150001, China;
2. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, China)
Abstract: The hydrogen storage material Mg-Ni-MnO2 was prepared by mechanical alloying under the hydrogen atmosphere and its phase transformation rate in hydrogen absorption was studied using the self-designed measurement apparatus. The experimental results show that the phase transformation rate has a maximum value in the hydrogen absorption; and the milling time has great effect on the time of maximum value appearance and maximum value of phase transformation rate. At the early stage, the rate is controlled by particle surface effect, and at the smooth stage, the mechanism of phase transformation is influenced by the particle size.
Key words: mechanical alloying; hydrogen storage material;phase transformation rate