Microstructure and phase evolutions of Mg-A1 powders ball milled in hydrogen atmosphere were investigated. Both in Mg-3%A1 (mass fraction) and Mg-9%AI systems, fl-MgH2 phase was observed upon a short milling time of...Microstructure and phase evolutions of Mg-A1 powders ball milled in hydrogen atmosphere were investigated. Both in Mg-3%A1 (mass fraction) and Mg-9%AI systems, fl-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 Mgl7All2. However, heating the milled powders of Mg-9%AI powders to 350 ~C resulted in the precipitation of Mg17A112. 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 offl-MgH2.展开更多
基金Projects(10JC407700,11ZR1417600)supported by the Science and Technology Committee of Shanghai,ChinaProject(12zz017)supported by the Shanghai Education Committee,China
文摘Microstructure and phase evolutions of Mg-A1 powders ball milled in hydrogen atmosphere were investigated. Both in Mg-3%A1 (mass fraction) and Mg-9%AI systems, fl-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 Mgl7All2. However, heating the milled powders of Mg-9%AI powders to 350 ~C resulted in the precipitation of Mg17A112. 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 offl-MgH2.