中国有色金属学报(英文版)
Transactions of Nonferrous Metals Society of China
| Vol. 23 No. 10 October 2013 |
（1. Shanghai Engineering Research Center of Magnesium Materials and Applications,
School of Materials Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;
2. State Key Laboratory of Metal Matrix Composites, School of Materials Science and Engineering,
Shanghai Jiao Tong University, Shanghai 200240, China）
Abstract:Microstructure and phase evolutions of Mg-Al powders ball milled in hydrogen atmosphere were investigated. Both in Mg-3%Al (mass fraction) and Mg-9%Al systems, β-MgH2 phase was observed upon a short milling time of 4 h and its maximum content of ~80% was reached after 32 h. Neither as-milled powders of the in the two systems contain Mg17Al12. However, heating the milled powders of Mg-9%Al powders to 350 °C resulted in the precipitation of Mg17Al12. DTA/TG analyses of those powders milled for 8-40 h showed that either well-developed peak doublets or shoulders were observed, which plausibly corresponded to the separate hydrogen desorption from different particle fractions of β-MgH2.
Key words: Mg alloy; reaction milling; hydriding; nanocrystalline magnesium hydride; peak doublets
