功能材料
功能材料
공능재료
JOURNAL OF FUNCTIONAL MATERIALS
2012年
20期
2751-2756
,共6页
方小飞%罗永春%高志杰%张国庆%康龙
方小飛%囉永春%高誌傑%張國慶%康龍
방소비%라영춘%고지걸%장국경%강룡
热处理%微观组织%A%B%。型相%电化学性能
熱處理%微觀組織%A%B%。型相%電化學性能
열처리%미관조직%A%B%。형상%전화학성능
annealing treatment%microstructure%A5 B19-type phase%electrochemical property
用感应熔炼方法熔炼A5B19型La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1合金,并在密闭容器中对合金进行不同温度(1173-1273K)下保温16h的热处理,采用电感耦合等离子发射光谱(ICP)、X射线衍射(XRD)、电子探针显微分析方法(EPMA)和电化学测试分析方法对比研究了退火温度对合金成分、微观组织和电化学性能的影响。结果表明,A5B19型合金组织主要由Ce5C019(Pr5Co19)型、PuNi3型和Ca-Cu5型等相组成,退火后舍金则形成以A5B19型(Pr5Co19和Ce5Co19)为主相的多相组织,随退火温度升高Pr5Co19型主相的相丰度逐渐增加,当T=1273K时其相丰度达到最大值87.8%(质量分数),而Ce5Co19型相仅为0.78%(质量分数)。电化学分析测试表明,退火温度对合金电极的活化性能和大电流放电特性影响不明显,但对电极容量和循环稳定性影响较大。在T=1273K退火后,合金电极放电容量为373.01mAh/g,经100次充放电循环后其电极容量保持率(S100)为90.20%,表现出较好的电化学性能。
用感應鎔煉方法鎔煉A5B19型La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1閤金,併在密閉容器中對閤金進行不同溫度(1173-1273K)下保溫16h的熱處理,採用電感耦閤等離子髮射光譜(ICP)、X射線衍射(XRD)、電子探針顯微分析方法(EPMA)和電化學測試分析方法對比研究瞭退火溫度對閤金成分、微觀組織和電化學性能的影響。結果錶明,A5B19型閤金組織主要由Ce5C019(Pr5Co19)型、PuNi3型和Ca-Cu5型等相組成,退火後捨金則形成以A5B19型(Pr5Co19和Ce5Co19)為主相的多相組織,隨退火溫度升高Pr5Co19型主相的相豐度逐漸增加,噹T=1273K時其相豐度達到最大值87.8%(質量分數),而Ce5Co19型相僅為0.78%(質量分數)。電化學分析測試錶明,退火溫度對閤金電極的活化性能和大電流放電特性影響不明顯,但對電極容量和循環穩定性影響較大。在T=1273K退火後,閤金電極放電容量為373.01mAh/g,經100次充放電循環後其電極容量保持率(S100)為90.20%,錶現齣較好的電化學性能。
용감응용련방법용련A5B19형La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1합금,병재밀폐용기중대합금진행불동온도(1173-1273K)하보온16h적열처리,채용전감우합등리자발사광보(ICP)、X사선연사(XRD)、전자탐침현미분석방법(EPMA)화전화학측시분석방법대비연구료퇴화온도대합금성분、미관조직화전화학성능적영향。결과표명,A5B19형합금조직주요유Ce5C019(Pr5Co19)형、PuNi3형화Ca-Cu5형등상조성,퇴화후사금칙형성이A5B19형(Pr5Co19화Ce5Co19)위주상적다상조직,수퇴화온도승고Pr5Co19형주상적상봉도축점증가,당T=1273K시기상봉도체도최대치87.8%(질량분수),이Ce5Co19형상부위0.78%(질량분수)。전화학분석측시표명,퇴화온도대합금전겁적활화성능화대전류방전특성영향불명현,단대전겁용량화순배은정성영향교대。재T=1273K퇴화후,합금전겁방전용량위373.01mAh/g,경100차충방전순배후기전겁용량보지솔(S100)위90.20%,표현출교호적전화학성능。
La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1 hydrogen storage alloys were prepared by induction melting and then annealed at different temperature(1173-1273K) in the closed container for 16h. The effect of annealing tempera- ture on the microstructure and electrochemical properties of La0.68Gd0.2Mg0.12Ni3.3CoO.3A10.1 were investigated by means of inductively coupled plasma(ICP), X-ray diffraction (XRD), electron probe micro-analysis (EP MA) and electrochemical measurements. The results showed that the A5B19 alloys mainly consisted of Ce5Co19- type(Pr5Co19-type), PuNi3-type and CaCus-type phase. Meanwhile, with increasing annealing temperature, Pr5Co19-type phase abundance in annealed alloys increased, and CesCo19 type phase abundance decreased. The Pr5Co19-type phase abundance was 87.75wt%, andCe5Co19-type phase abundance was only 0.78wt% when an- nealing temperature was 1273K. The electrochemical measurements showed that these alloys had little effects on activation performance under different annealing temperature, but it was great impact on electrode capacity and cycle stability. The discharge capacity of the alloys reached 373. 01mAh/g when annealing temperature was 1273K. After 100 charge-discharge cycles, the discharge capacity retention rate(S100)of the alloy electrode(T= 1273K) reached 90.2%.