La0.55Pr0.05NdxMg0.4-xNi3.3Al0.1(x=0.10-0.20)储氢合金的研究Ⅰ：相结构和气相吸放氢性能  

Investigation on the Characteristics of La_(0.55)Pr_(0.05)Nd_xMg_(0.4-x)Ni_(3.3)Al_(0.1)(x=0.10~0.20) Hydrogen Storage Alloys Part I: Phase Structures and Hydrogen Storage

作　　者：闫慧忠[1] 孔繁清[2] 熊玮[2] 李宝犬 李金[2] 朱敏[1] 

机构地区：[1]华南理工大学机械工程学院,广东广州510641 [2]包头稀土研究院,内蒙古包头014030

出　　处：《稀土》2008年第1期1-7,共7页Chinese Rare Earths

基　　金：国际科技合作项目(2006DFB52550);国家自然科学基金(20363001)

摘　　要：中频感应熔炼法制备了La0.55Pr0.05NdxMg0.4-xNi3.3Al0.1(x=0.100、.15、0.20)储氢合金。通过X射线衍射(XRD)和Rietveld方法分析了每个合金的相结构,分析结果表明,由于Nd/Mg比不同,三个合金的相组成不完全相同。同时应用扫描电镜(SEM)观察了合金的形貌并结合能谱(EDS)方法测定了各相的组成,测定结果与XRD分析结果有所不同。La0.55Pr0.05NdxMg0.4-xNi3.3Al0.1(x=0.10、0.15、0.20)合金在313 K第一次吸放氢的P-C-T曲线显示出两个平台压力,分别对应于(La,Mg)2(Ni,Al)7相和La(Ni,Al)5相。合金的储氢容量随x值的增大先增加后减小,这种变化规律可能与合金中储氢相的丰度以及晶胞体积有关。该系列合金的吸/放氢动力学曲线表明,Nd含量适中的合金的吸/放氢动力学性能相对较好。La0.55Pr0.05NdxMg0.4-xNi3.3Al0.1（x=0.10-0.20） hydrogen storage alloys were prepared by induction melting. The phase structures were obtained from XRD patterns and Rietveld analyses of each alloy. The results indicate that the phase composition of as - cast alloys is not all same due to the difference of Nd/Mg ratio. At the same time, the surface morphology of each alloy was observed by scanning electron microscope （SEM） and the phase composition of each alloy was analyzed by energy - dispersive X - ray spectrometer （EDS）. It is found that the analytical result of EDS is different from that of XRD. P - C - T curves were measured for the La0.55Pr0.05NdxMg0.4-xNi3.3Al0.1（x=0.10-0.20） alloys at 313K. The results indicate that as- cast alloys shows two pressure plateaus, corresponding to （La,Mg）2（Ni,Al）7 phase and La（Ni,Al）5 phase, respectively. The hydrogen absorption capacities of as- cast alloys first increase and then decrease with increasing x value, which could correlate with the phase abundance and cell volume of the hydrogen storage phases in alloys. The absorption/desorption kinetics curves of the alloys show that ap- propriate Nd/Mg ratio is favorable to improve the hydrogen storage capacity and the kinetics performances.

关 键 词：RE-Mg-Ni系储氢合金 相结构 气相吸放氢 P-C-T曲线 动力学性能 

分 类 号：TG139.7[一般工业技术—材料科学与工程] TG146.4[金属学及工艺—合金]