The microstructuralchangeof mechanicalalloyingof pureelemental Mg Nipowders wasin vestigated by transmission electronic microscopy ( TEM). The experimental results showed thatafter5 h milling, Mg2 Ni phase precipit...The microstructuralchangeof mechanicalalloyingof pureelemental Mg Nipowders wasin vestigated by transmission electronic microscopy ( TEM). The experimental results showed thatafter5 h milling, Mg2 Ni phase precipitated mainly from Mg grain , and no Mg2 Ni wasfound in Ni matrix. Thiscan be attributed tothe asym metricalinterdiffusion between Mg and Ni atom , which causesthecontent of Mg in Ni grain far below thestoichiometric composition of Mg2 Ni. After the growth of Mg2 Ni grain, the severe mechanical deforma tion resulting from mechanicalalloying led tothetransformation of Mg2 Ni from hexagonal tofccstructure partially, which makes Mg2 Ni grain in a composite microstructure fcc + hcp.展开更多
采用固溶烧结法制备了Mg_2Ni_(1-x)Co_x(x=0.10,0.15,0.20)合金,利用X射线衍射仪和压力-组成-温度测试仪等研究了Co含量对合金相结构和储氢性能的影响.结果表明,合金由Mg_2Ni型Mg_2(Ni,Co)主相及少量Mg和Mg Ni3Co新相组成.Mg2(Ni,Co)具...采用固溶烧结法制备了Mg_2Ni_(1-x)Co_x(x=0.10,0.15,0.20)合金,利用X射线衍射仪和压力-组成-温度测试仪等研究了Co含量对合金相结构和储氢性能的影响.结果表明,合金由Mg_2Ni型Mg_2(Ni,Co)主相及少量Mg和Mg Ni3Co新相组成.Mg2(Ni,Co)具有良好的可逆储氢性能,吸氢形成Mg_2Ni_(0.9)Co_(0.1)H_4型四元氢化物,其具有与父系氢化物HT-Mg_2NiH_4相近的放氢焓变(ΔHd=63.9 k J/mol H2).Mg_2Ni_(1-x)Co_x(x=0.10,0.15,0.20)合金具有良好的放氢动力学性能,二维相界面迁移为放氢过程的控制步骤.随着Co含量的增加,合金的放氢活化能(Ea)降低,其中,Mg_2Ni_(0.8)Co_(0.2)的Ea降低到54.0 k J/mol.展开更多
文摘The microstructuralchangeof mechanicalalloyingof pureelemental Mg Nipowders wasin vestigated by transmission electronic microscopy ( TEM). The experimental results showed thatafter5 h milling, Mg2 Ni phase precipitated mainly from Mg grain , and no Mg2 Ni wasfound in Ni matrix. Thiscan be attributed tothe asym metricalinterdiffusion between Mg and Ni atom , which causesthecontent of Mg in Ni grain far below thestoichiometric composition of Mg2 Ni. After the growth of Mg2 Ni grain, the severe mechanical deforma tion resulting from mechanicalalloying led tothetransformation of Mg2 Ni from hexagonal tofccstructure partially, which makes Mg2 Ni grain in a composite microstructure fcc + hcp.
文摘采用固溶烧结法制备了Mg_2Ni_(1-x)Co_x(x=0.10,0.15,0.20)合金,利用X射线衍射仪和压力-组成-温度测试仪等研究了Co含量对合金相结构和储氢性能的影响.结果表明,合金由Mg_2Ni型Mg_2(Ni,Co)主相及少量Mg和Mg Ni3Co新相组成.Mg2(Ni,Co)具有良好的可逆储氢性能,吸氢形成Mg_2Ni_(0.9)Co_(0.1)H_4型四元氢化物,其具有与父系氢化物HT-Mg_2NiH_4相近的放氢焓变(ΔHd=63.9 k J/mol H2).Mg_2Ni_(1-x)Co_x(x=0.10,0.15,0.20)合金具有良好的放氢动力学性能,二维相界面迁移为放氢过程的控制步骤.随着Co含量的增加,合金的放氢活化能(Ea)降低,其中,Mg_2Ni_(0.8)Co_(0.2)的Ea降低到54.0 k J/mol.
基金Projects (51161015,51371094) supported by the National Natural Science Foundation of ChinaProject (2011ZD10) supported by the Natural Science Foundation of Inner Mongolia,China