CAJ | 학술논문

采用二步熔炼法制备了Mm(NiCoMnAl)5/5%(质量分数)Mg2 Ni复合储氢合金,并对其在不同温度(1023、1123和1223K)下进行退火热处理10h。用X射线衍射(XRD)、扫描显微镜(SEM)和电化学测试方法研究了退火温度对合金结构和电化学性能的影响。结果表明,铸态 Mm (NiCoMnAl)5/5%(质量分数)Mg2 Ni 复合合金由 LaNi5相和少量的 Mg2 Ni 相组成,而退火态合金由 LaNi5相和(La,Mg)Ni3新相组成。合金的最大放电容量和高倍率放电性能随退火温度的升高呈现出先增强后减弱的变化规律,其中退火温度为1023K 时,合金电极的上述性能均达到最佳。合金的容量保持率随退火温度的升高而单调地增大,60次充放电循环后容量保持率从铸态合金的86.6%增大到退火合金(1223K)的92.4%。
채용이보용련법제비료Mm(NiCoMnAl)5/5%(질량분수)Mg2 Ni복합저경합금,병대기재불동온도(1023、1123화1223K)하진행퇴화열처리10h。용X사선연사(XRD)、소묘현미경(SEM)화전화학측시방법연구료퇴화온도대합금결구화전화학성능적영향。결과표명,주태 Mm (NiCoMnAl)5/5%(질량분수)Mg2 Ni 복합합금유 LaNi5상화소량적 Mg2 Ni 상조성,이퇴화태합금유 LaNi5상화(La,Mg)Ni3신상조성。합금적최대방전용량화고배솔방전성능수퇴화온도적승고정현출선증강후감약적변화규률,기중퇴화온도위1023K 시,합금전겁적상술성능균체도최가。합금적용량보지솔수퇴화온도적승고이단조지증대,60차충방전순배후용량보지솔종주태합금적86.6%증대도퇴화합금(1223K)적92.4%。
Mm(NiCoMnAl)5/5wt% Mg2 Ni composite hydrogen storage alloys were prepared by two-step remelt-ing and then annealed at 1023,1123 and 1223K for 10h.The effect of annealing temperature on the microstruc-ture and electrochemical properties of Mm(NiCoMnAl)5/5wt% Mg2 Ni were investigated by means of X-ray dif-fraction (XRD),scanning electron microscope (SEM),and electrochemical measurements.The results showed that the as-cast composite alloy was composed of the LaNi5 phase and a small amount of the Mg2 Ni phase. However,the annealed alloys consisted of the LaNi5 phase and a (La,Mg)Ni3 new phase.The maximum dis-charge capacity and high rate dischargeability of the alloys increased firstly and then decreased with increasing annealing temperature.The alloy annealed at 1023K exhibited the best the maximum discharge capacity and high rate dischargeability.The capacity retention increased monotonically with the increase of annealing tem-perature,and the capacity retention of the alloy increased from 86.6% (as-cast)to 92.4% (annealed at 1223K) after 60 charge-discharge cycles.