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关于电化学方面论文例文,与医学学位文湖北,硕士学位文的通知相关毕业论文范文
本论文是一篇关于电化学方面毕业论文范文,关于医学学位文湖北,硕士学位文的通知相关毕业论文格式模板范文。免费优秀的关于电化学及合金及控制工程方面论文范文资料,适合电化学论文写作的大学硕士及本科毕业论文开题报告范文和学术职称论文参考文献下载。
thatelastic-plasticandthermal-mechanicalcoupledFEMcouldcorrectlyreflectmetaldeformation.Underthebackgroundofthedevelopmentofthinslabrollinginourcountry,thepresentedtemperatureandmechanicalpropertyparametersdistributionandrulesmayeupwithreferencetoindustrialproduction.
Keywords:CSPMarcheat-mechanicalcoupledFEMsimulation
论文题目:快淬AB5型贮氢合金电化学性能及其微观结构的研究
TheInvestigationsonElectrochemicalPerformancesand
MicrostructuresofRapidQuenchingAB5-typeHydrogenStorageAlloys
研究生姓名:王国清
导师姓名:张羊换教授
专业:材料加工工程
摘 要:
AB5型稀土系贮氢合金,作为Ni/MH电池负极材料已得到大量研究和广泛应用.为了提高Ni/MH电池的市场竞争力,降低贮氢合金的生产成本和提高合金的电化学性能成为贮氢合金研究的主要方向.目前研究的焦点是如何提高低钴,无钴贮氢合金的电化学循环稳定性.本文旨在通过合金成分的优化调整,同时结合适当的快淬工艺,改善低钴无钴贮氢合金的循环稳定性,制备出综合性能优异的贮氢合金电极材料.
本文主要应用熔炼法和真空快淬技术制备AB5型贮氢合金,用开口式三电极系统测试合金的电化学性能,用XRD分析了铸态及快淬态合金的相组成及相结构,用SEM和光学显微镜观察了铸态及快淬态合金的微观组织形貌,用TEM观察了铸态及快淬态合金的形貌并用SAD确定其晶态.全面研究了合金微观结构与其电化学性能的联系,得到如下一些主要结论:
1.综合研究了Mm(NiMnSiAl)4.3Co0.6-xFex(x等于0,0.2,0.4,0.6)系列铸态和快淬态合金的微观结构及电化学性能.结果表明,Fe替代Co导致合金的电化学容量下降,但不同程度的改善了合金的循环稳定性.Fe替代Co对快淬态合金循环寿命的提高比较显着,这主要是由于随Fe替代量的增加,快淬态合金的晶粒明显细化.快淬工艺可以极大地提高合金的循环寿命.
2.对铸态及快淬态低钴无钴LaxMm1-x(NiMnSiAlFe)4.7Co0.2(x等于0,1)和LaxMm1-x(NiMnSiAlFe)4.9(x等于0,1)两个系列铸态和快淬态合金的研究结果表明,La替代Mm使合金放电容量提高,其主要原因是合金中第二相的消失和晶胞体积的增大.
3.研究表明,通过以Fe替代Co,成分优化设计以及应用真空快淬工艺研制低钴无钴AB5型贮氢合金是可行的.实验发现两种成分的低钴无钴合金可以达到实用化需求.这两种合金成分是La(NiMnSiAlFe)4.7Co0.2和La(NiMnSiAlFe)4.9,活化次数为2次,最大放电容量分别为309.42mAh/g和304.47mAh/g,循环寿命分别为370和300次.
关 键 词:AB5型贮氢合金,低钴无钴,快淬,循环稳定性
ABSTRACT
AB5-typerare-earth-basedhydrogenstoragealloy,asthenegativeelectrodematerialoftheNi/MHbatteries,hasbeenextensivelyinvestigatedandwidelyapplied.InordertoexaltthepetitionabilityofNi-MHbatteriesintherechargeablebatterymarket,theinvestigationontheAB5-typehydrogenstoragealloyhasbeencarryingouttoenhancetheelectrochemicalperformancesandreducetheproductioncostofthealloy.Atpresent,theinvestigationfocusontheAB5-typehydrogenstoragealloyishowtoincreasethecyclestabilityofLow-CoandCo-freeelectrodealloy.Thisthesisintendstogetakindofhydrogenstoragealloywithgreatsyntheticalpropertiesthroughoptimizingthepositionandrightrapidquenchingtechnology.
AB5-typehydrogenstoragealloyswerepreparedbycastingandrapidquenching.Theelectrochemicalperformancesoftheexperimentalalloysweremeasuredbyanopentri-electrodesystem.Themicrostructuresoftheas-castandquenchedalloyswerestudiedsystematically:thephasestructureswereanalyzedbyXRD,themicrostructuresandmorphologieswereobservedbySEMandOpticsmicroscope,thecrystallinestateandmorphologiesweredeterminedbySADandTEM.Theinfluencesofrapidquenchingtechnologyonthemicrostructuresandelectrochemicalperformancesoftheexperimentalalloyswereresearchedindetail,andsomeimportantconclusionswereobtained.
1.Themicrostructuresandelectrochemicalperformancesoftheas-castandquenchedMm(NiMnSiAl)4.3Co0.6-xFex(x等于0,0.2,0.4,0.6)alloysweresyntheticallyinvestigated.TheresultsshowthatsubstitutionFeforColeadstodecreaseofthedischargecapacityandimproveofthecyclelifeofthealloystosomedegree.Especially,theeffectofsubstitutionFeforCoonthecyclelifeoftheas-quenchedalloysisoutstanding.ThisismainlyattributedtothegrainrefinementproducedbytheincreaseoftheamountofFecontent.Rapidquenchingcangreatlyimprovethecyclelifeofthealloy.
2.Theelectrochemicalperformancesandmicrostructuresoftheas-castandquenchedLow-CoandCo-freeLaxMm1-x(NiMnSiAlFe)4.7Co0.2(x等于0,1)andLaxMm1-x(NiMnSiAlFe)4.9(x等于0,1)electrodealloyswereresearchedandresultsshowthat,thesubstitutionLaforMmmakestheincreaseofthedischargecapacityofLow-CoandCo-freealloys.ThemainreasonisthatthesecondaryphasedisappearsandthelatticevolumeaugmentswhenLasubstitutesMmintheLow-CoandCo-freealloys.
3.TheinvestigationsshowthatitisfeasibletoprepareanddeveloptheLow-CoandCo-freeAB5-typehydrogenstoragealloysbysubstitutionFeforCo,ponentoptimizingdesignandusingrapidquenchingtechnology.TwokindsoftheLow-CoandCo-freealloyswhichcanattaintherequirementofthepracticalapplicationarediscovered.ThealloysareLa(NiMnSiAlFe)4.7Co0.2andLa(NiMnSiAlFe)4.9withtheactivationpropertyof2cycles,themaximumdischargecapacityof309.42mAh/gand304.47mAh/g,andthecyclelifeof370and300cyclesrespectively.
Keywords:AB5-typehydrogenstoragealloy,Low-CoandCo-free,rapidquenching,cyclestability
论文题目:热处理工艺及稀土元素对Ni-Mn-Ga磁性形状记忆合金性能的影响
InfluenceofHeatTreatmentProcessandRareEarthson
thePropertiesofNi-Mn-GaMagicShapeMemoryAlloys
研
关于电化学方面论文例文,与医学学位文湖北,硕士学位文的通知相关毕业论文范文参考文献资料：