铸态及退火La_(1.9)Ti_(0.1)MgNi_9合金的贮氢性能(英文)  

Hydrogen Storage Properties of As-Cast and Annealed La_(1.9)Ti_(0.1)MgNi_9 Alloys

作　　者：蒋卫卿[1] 周正诚[1,2] 黄春玉[1] 蓝志强[1] 郭进[1] 

机构地区：[1]广西大学,广西南宁530004 [2]右江民族医学院,广西百色533000

出　　处：《稀有金属材料与工程》2010年第11期1888-1892,共5页Rare Metal Materials and Engineering

基　　金：the National Natural Science Foundation of China (50861003);the Natural Science Foundation of Guangxi (2010GXNSFD013004);the Foundation of Key Laboratory of National Education Ministry for Nonferrous Metals and Materials Processing Technology (GXKFJ09-15);the Foundation of Guangxi Department of Education (200911MS07);the Foundation of Guangxi University (X081056)

摘　　要：采用磁悬浮感应熔炼及退火处理的方法,制备La1.9Ti0.1MgNi9合金。对合金样品的XRD、PCT和电化学测试表明,所有样品均由多相组成,LaNi5相为主相。当退火温度达到1173K时,合金中LaMg2Ni9相消失,Ti2Ni相出现。退火处理能提高合金的晶化程度、降低吸放氢平台压。退火1073K合金的有效吸氢量较高,在303K时达到1.25%(质量分数)。La1.9Ti0.1MgNi9合金退火后,放电容量、循环稳定性以及高倍率放电性能得到极大改善,以1173K退火合金电化学性能较好,其最大放电容量为377mAh/g,1100mA/g电流密度下的高倍率放电性能为0.839,经112次充放电循环后放电容量保持率为60%。La1.9Ti0.1MgNi9 alloys were prepared by magnetic levitation melting followed by annealing treatments. The results of XRD, PCT and electrochemical measurements show that all samples possess a multiphase structure, and LaNi5 phase is the main phase. LaMg2Ni9 phase disappears and Ti2Ni phase appears at 1173 K. Annealed alloys exhibit higher compositional homogeneity and lower absorption/desorption plateau pressures compared to as-cast alloy. The effective hydrogen storage capacity of the alloy annealed at 1073 K is the highest, and it reaches 1.25% (mass fraction) at 303 K. Annealing not only enhances the discharge capacity, but also improves the cyclic stability and the high rate dischargeability markedly. La1.9Ti0.1MgNi9 alloy annealed at 1173 K presents good electrochemical performance with the maximum discharge capacity of 377 mAh/g, the HRD1100 of 0.839 and the retention of discharge capacity of 60% after 112 charge/discharge cycles.

关 键 词：铸态 退火处理 退火合金 discharge capacity 高倍率放电性能 electrochemical performance high rate dischargeability hydrogen storage capacity 最大放电容量 MULTIPHASE structure LEVITATION melting 有效吸氢量 循环稳定性 电化学性能 电化学测试 充放电循环 LANI5 retention effective 质量分数 

分 类 号：TG139.7[一般工业技术—材料科学与工程]