CAJ | 학술논문

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1173 K时,合金中LaMg2Ti9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1073 K合金的有效吸氢量较高,在303 K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1173 K退火合金电化学性能较好,其最大放电容量为377 mAh/g,1100 mA/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%.
채용자현부감응용련급퇴화처리적방법,제비La1.9Ti0.1MgNi9합금.대합금양품적XRD、PCT화전화학측시표명,소유양품균유다상조성,LaNi5상위주상.당퇴화온도체도1173 K시,합금중LaMg2Ti9상소실,Ti2Ni상출현.퇴화처리능제고합금적정화정도、강저흡방경평태압.퇴화1073 K합금적유효흡경량교고,재303 K시체도1.25%(질량분수).La1.9Ti0.1MgNi9합금퇴화후,방전용량、순배은정성이급고배솔방전성능득도겁대개선,이1173 K퇴화합금전화학성능교호,기최대방전용량위377 mAh/g,1100 mA/g전류밀도하적고배솔방전성능위0.839,경112차충방전순배후방전용량보지솔위60%.
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.