机械球磨制备La_2Mg_(17)/Ni复合材料的微观结构及气态吸放氢性能

Microstructures and hydriding/dehydriding characteristics of La_2Mg_(17)/Ni composites by mechanical milling

为提高La2Mg17贮氢合金的吸放氢性能,以机械球磨La2Mg17+Ni+NbF5在氩气为保护气氛围下制备复合材料。采用XRD分析了球磨后复合材料的微观结构,用SEM观察了其形貌。通过自动控制的Sieverts设备测试了材料的吸放氢动力学性能。研究表明混合球磨后复合材料的吸放氢性能有了显著的提高,进一步说明Ni粉、NbF5促使了材料纳米晶/非晶结构的形成,而该结构的形成是材料吸放氢性能提高的主要原因。

In order to improve the hydriding/dehydriding property of the La2Mg17 alloys, La2 Mg17＋Ni＋NbF5mechanical milling were performed in an argon protective atmospheres. The structure of mechanical milling composites was characterized by XRD and SEM, respectively. The hydrogen storage properties were measured by automatically controlled Sieverts apparatus. The research showed that absorbed/desorbed hydrogen capabili- ty significantly enhanced due to ball-milling technology, and further indicated that Ni powder and NbF5 promp- ted the nanocrystalline/amorphous structures formation, which was the main reason of hydrogenation/dehydro- genation improvement.