Mg2.1Ni与Mg1.6La0.5Ni合金的组织结构与吸放氢性能  

Structure and hydriding/dehydriding property of Mg2.1Ni and Mg1.6La0.5Ni alloys

作　　者：李敏[1,2] 杨丽颖[3] 董小平[3] 陈亚芳[3] 李旭 张雷 

机构地区：[1]河北大学电子信息工程学院,河北保定071000 [2]河北大学光伏技术虚拟仿真实验教学中心,河北保定071000 [3]河北大学质量技术监督学院,河北保定071000

出　　处：《材料热处理学报》2018年第3期15-20,共6页Transactions of Materials and Heat Treatment

基　　金：国家自然科学基金(51371094);河北省自然科学基金(E2018201235,E2014201120,E2015201203);河北大学实验室开放项目基金(sy201676,201650)

摘　　要：采用SEM与XRD分析了Mg2.1Ni与Mg1.6La0.5Ni合金的显微组织与相结构,用Sievert法测试了合金的活化性能以及吸放氢动力学。结果表明：Mg2.1Ni合金的室温组织为脊椎状的Mg2Ni相和层片状Mg2Ni/Mg共晶组织,而Mg1.6La0.5Ni合金组织为块状La2Mg17相、长条状LaMg3相镶嵌于Mg2Ni基体相中;合金的吸氢活化性能与成分有关,Mg2.1Ni合金的活化性能相对较差,而Mg1.6La0.5Ni合金的活化性能优异;合金的吸放氢动力学与La加入有关,Mg1.6La0.5Ni合金的吸放氢动力学优于Mg2.1Ni合金,这归因于La加入使合金组织疏松、较多的晶界/相界、以及具有催化效应的La4H12.19相出现,但La4H12.19相具有较高的热稳定性,这降低合金氢化物的放氢率。Microstructure and phase structure of Mg2.1Ni and Mg1.6La0.5Ni alloys were studied by means of scanning electron microscopy（SEM） and X-ray diffraction（XRD）,the activation performance and hydriding/dehydriding dynamics of the alloys were tested by Sievert method.The results show that the microstructure of the Mg2.1Ni alloy at room temperature is composed of backbone shape Mg2Ni phase and lamellar Mg2Ni/Mg eutectic structure,while the Mg1.6La0.5Ni alloy is massive La2Mg17 phase,and strip LaMg3 phase is embedded in Mg2Ni matrix phase.The activation performance of hydrogen absorption of the alloy is related to the composition of the alloy,and the activation performance of the Mg2.1Ni alloy is relatively poor,while the activation performance of the Mg1.6La0.5Ni alloy is excellent.Due to the addition of La,the Mg1.6La0.5Ni alloy has loose structure,many grain boundary/phase boundaries,and La4H12.19 phase with catalytic effect,therefore,the kinetics of hydrogen absorption and desorption of the Mg1.6La0.5Ni alloy is better than that of the Mg2.1Ni alloy,but the La4H12.19 phase has high thermal stability,which reduces the hydrogen desorption ratio of the alloy hydride.

关 键 词：MG-NI合金 La元素 微观组织结构 吸放氢动力学 

分 类 号：TG139.7[一般工业技术—材料科学与工程]