Microstructure and remarkably improved hydrogen storage properties of Mg_2Ni alloys doped with metal elements of Al, Mn and Ti  

添加金属元素Al、Mn和Ti后Mg_2Ni合金的显微组织及其显著改善的储氢性能（英文）

作　　者：Hai-chang ZHONG Jing-bo XU Chun-hai JIANG Xiang-jun LU 钟海长;徐敬博;姜春海;卢向军(厦门理工学院功能材料及其应用福建省重点实验室,厦门361024;厦门理工学院材料科学与工程学院,厦门361024)

机构地区：[1]Fujian Provincial Key Laboratory of Functional Materials and Applications,Xiamen University of Technology,Xiamen 361024,China [2]School of Materials Science and Engineering,Xiamen University of Technology,Xiamen 361024,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第12期2470-2477,共8页中国有色金属学报（英文版）

基　　金：Project (2016J01266) supported by the Natural Science Foundation of Fujian Province,China;Project (JZ160474) supported by the Science and Technology Project of Education Department of Fujian Province,China

摘　　要：Mg2Ni0.7M0.3(M=Al,Mn and Ti)alloys were prepared by solid phase sintering process.The phases and microstructure of the alloys were systematically characterized by XRD,SEM and STEM.It was found that Mg3MNi2intermetallic compounds formed in Mg2Ni0.7M0.3alloys and coexisted with Mg and Mg2Ni,and that radius of M atoms closer to that of Mg atom was more beneficial to the formation of Mg3MNi2.The hydrogen storage properties and corrosion resistance of Mg2Ni0.7M0.3alloys were investigated through Sievert and Tafel methods.Mg2Ni0.7M0.3alloys exhibited remarkably improved hydrogen absorption and desorption properties.Significantly reduced apparent dehydriding activation energy values of-46.12,-59.16and-73.15kJ/mol were achieved for Mg2Ni0.7Al0.3,Mg2Ni0.7Mn0.3and Mg2Ni0.7Ti0.3alloys,respectively.The corrosion potential of Mg2Ni0.7M0.3alloys shifted to the positive position compared with Mg2Ni alloy,e.g.there was a corrosion potential difference of0.110V between Mg2Ni0.7Al0.3alloy(-0.529V)and Mg2Ni(-0.639V),showing improved anti-corrosion properties by the addition of Al,Mn and Ti.采用固相烧结方法制备Mg_2Ni_(0.7)M_(0.3 )(M=Al, Mn, Ti)合金。利用X射线衍射仪、扫描电镜和扫描透射电镜对合金的相组成和显微组织进行系统表征。结果发现,Mg_2Ni_(0.7)M_(0.3)合金中形成了具有面心立方结构的金属间化合物Mg_3MNi_2,其与Mg和Mg_2Ni共存;且M原子半径与Mg原子半径越接近,越有利于Mg_3MNi_2的形成。采用Sievert和Tafel方法对Mg_2Ni_(0.7)M_(0.3)合金的储氢性能和耐腐蚀性能进行研究。Mg_2Ni_(0.7)M_(0.3)合金的吸/放氢性能得到明显改善。Mg_2Ni_(0.7)Al_(0.3)、Mg_2Ni_(0.7)Mn_(0.3)和Mg_2Ni_(0.7)Ti_(0.3)合金的脱氢反应的激活能较Mg_2Ni的激活能明显降低,分别为-46.12、-59.16和-73.15k J/mol。与Mg_2Ni合金相比,Mg_2Ni_(0.7)M_(0.3)合金的腐蚀电位向正方向移动,如Mg_2Ni_(0.7)Al_(0.3)合金(-0.529 V)与Mg_2Ni合金(-0.639 V)的腐蚀电位差为0.110 V,表明添加Al、Mn和Ti能使合金的耐腐蚀性能得到显著提高。

关 键 词：MG2NI Mg3MNi2 hydriding kinetics dehydriding activation energy anti-corrosion properties 

分 类 号：TG146.22[一般工业技术—材料科学与工程]