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22 个结果
  • 简介:Puretungsten(PW)andW-1wt%La2O3(WL10)werepreparedbypowdermetallurgicalroutefollowedbytheswaging+rollingprocess.Thelogarithmicstrainsare0,0.37,0.58,and0.98forWL10and0,0.58forPW.Heattreatmentswereperformedattemperaturesvariedfrom1,573to2,173Ktodeterminetherecrystallizationtemperature.Recrystallizationtemperaturesare1,973and2,173KforWL1(logarithmicstrainof0.37)andWL3(logarithmicstrainof0.98),respectively.ButinthecaseofWL2(logarithmicstrainof0.58),fullrecrystallizationisnotachievedattemperatureofabove2,173K.Furthermore,therecrystallizationtemperatureofPWwithlogarithmicstrainof0.58isatleast300KlowerthanthatoftheequivalentWL10sample.Moreover,theincreaseofrecrystallizationtemperatureinhibitsthestrengthdegradationofWL2:sampleslose4%and22%strengthwhenannealedat1,573and1,973Kcomparedwithroomtemperature(RT)sample.Finally,thetextureevolutionfortheswaged+rolledWL10issignificantlyrelatedtothedeformationdegree:thedominatedorientationis<001>forWL2while<110>forWL3.

  • 标签: 再结晶温度 变形程度 纯钨 对数应变 轧制工艺 强度退化
  • 简介:Theaxialandradialconvectiveflow,temperaturefluctuationanddistributionintheHMCZsiliconmeltarestudiedtentatively.Theexperimentalresultsshowthattheaxialandradialconvectivespeeds,thetempera-turevariationandtheradialtemperaturegradient,paralleltomagneticfieldandnearmeltsurface,alldecrease,buttheaxisymmetryoftemperaturedistributionnolongerexistswhenthemagneticfieldisapplied.

  • 标签: MAGNETIC FIELD Temperature distribution CONVECTIVE FLOW
  • 简介:Permanentmagneticmaterialscapableofoperatingathightemperatureupto500°Chavewidepotentialapplicationsinfieldssuchasaeronautics,space,andelectroniccars.SmCoalloysarecandidatesforhightemperatureapplications,sincetheyhavelargemagnetocrystallineanisotropyfield(6–30T),highCurietemperature(720–920°C),andlargeenergyproduct([200kJám-3)atroomtemperature.However,thehighestservicetemperatureofcommercial2:17typeSmComagnetsisonly300°C,andmanyeffortshavebeendevotedtodevelopnovelhightemperaturepermanentmagnets.ThisreviewfocusesonthedevelopmentofthreekindsofSmCobasedmagnets:2:17typeSmComagnets,nanocrystallineSmComagnets,andnanocompositeSmComagnets.Theoxidationprotection,includingalloyingandsurfacemodification,ofhightemperaturepermanentmagnetsisdiscussedaswell.

  • 标签: 高温永磁材料 高温永磁体 钐钴合金 磁晶各向异性场 最高使用温度 纳米复合材料
  • 简介:Thecombinedquadraticorthogonalregressionmethodofexperimentdesignwasemployedtoexploretheeffectsofprocessparametersofplasmanitridingoftantalumsuchastotalpressure,temperatureandoriginalhydrogenmolarfractiononthehardness,roughnessandstructureofnitridingsurfaces.Theregressionequationsofhardness,roughnessandstructureweregivenaccordingtotheresultsofregressionandstatisticanalysis.Andthediffusionactivationenergyofnitrogenintantalumonplasmanitridingconditionswascalculatedaccordingtotheexperimentaldataofhardnessofplasma-nitridingoftantalumvstimeandtemperature.Thediffusionactivationenergycalculatedbelongsto(155.49+10.51)kJ/mol(783-983K).

  • 标签: 渗氮等离子体 温度 压力 正交回归法 扩散活化能
  • 简介:IntroductionIMI829titaniumaloyisakindofhightemperaturenearαaloy.Itsservicetemperatureisupto580℃.IthasbeenusedinRB211525E4en...

  • 标签: YTTRIUM ALLOY MICROSTRUCTURE PROPERTY
  • 简介:Ni83Fe17filmswithathicknessofabout100nmweredepositedonthermaloxidizedsiliconsubstratesatambienttemperature,240,350,and410℃byDCmagnetronsputtering.Thedepositionratewasabout0.11nm/s.Theas-depositedfilmswereannealedat450,550,and650℃,respectively,inavacuumlowerthan3x10-3Pafor1h.TheNi83Fe17filmsmainlygrowwithacrystallineorientationof[111]inthedirectionofthefilmgrowth.Withtheannealingtemperatureincreasing,the[111]orientationenhances.Forfilmsdepositedatallfourdifferenttemperatures,thesignificantimprovementonanisotropicmagnetoresistanceoccursattheannealingtemperaturehigherthan550℃.Butforfilmsdepositedatambienttemperaturesand240℃,theanisotropicmagnetoresistancecanonlyrisetoabout1%after650℃annealing.Forfilmsdepositedat350℃and410℃,theanisotropicmagnetoresistancerisestoabout3.8%after650℃annealing.Theatomicforcemicroscopy(AFM)observationshowsasignificantincreaseingrainsizeofthefilmdepositedat350℃atter650℃annealing.Thedecreaseinresistivityandtheincreaseinanisotropicmagnetoresistancearecausedbythedecreaseinpointdefects,theincreaseingrainsize,andtheimprovementinlatticestructureintegrityofthefilms.

  • 标签: 磁阻性质 NiFe膜 退火 各向异性 凝聚体物理学 磁电管喷镀
  • 简介:Theeffectofsolidificationrateonthemicrostructuredevelopmentofnickel-basedsuperalloyunderthetemperaturegradientof500K·cm-1wasstudied.Theresultsshowthat,withtheincreaseofdirectionalsolidificationratefrom50to800μm·s-1,boththeprimaryandthesecondarydendritearmspacingsofthealloydecreasegradually,andthedendritemorphologiestransformfromcoarsedendritetosuperfinedendrite.Thesizesofallprecipitatesinthesuperalloydecreasegradually.Themorphologyof...

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  • 简介:1IntroductionOverthepastfewyears,intensiveworkhasbenmadetoachievemulticolororfulcolorthinfilmelectroluminescence(EL)device...

  • 标签: ELECTROLUMINESCENCE SUBSTRATE TEMPERATURE SrS∶HoF 3 EL
  • 简介:一系列TbDyFe电影被DC磁控管劈啪作响准备。阶段结构和样品电影的磁性上的底层温度和退火的温度的效果被调查。退火的处理在微观结构和样品的磁性上有重要影响。XRD获得的结果显示在温度扔的电影比525敨?祥獥Δ降低

  • 标签: TbDyFe薄膜 无定形 基底温度 退火温度
  • 简介:各向异性的MnBi/NdFeB(0wt%的MnBi内容,20?wt%,40?wt%,60?wt%,80?wt%,并且100?wt%)混合结合的磁铁被用MnBi粉末和再结合(HDDR)NdFeB粉末塑造压缩准备。在房间温度的磁性的大小证明与MnBi内容增加,MnBi/NdFeB混血儿的磁性结合了磁铁都逐渐地减少,当混合磁铁的密度几乎线性地改善时。在293-398的一个温度范围?K,混合磁铁的coercivity温度系数从0.59逐渐地改善?%比较。建模和频率与二低角落频率认为压力消除阀门是一个秒顺序系统是合理的试验性的结果表演。PID控制,死了的乐队赔偿控制和鷸?鷸??

  • 标签: 粘结钕铁硼磁体 混合磁体 粘结磁体 各向异性 磁性能 MnBi
  • 简介:AseriesofPr-CothinfilmsweredepositedontheSi(100)substrateswithCrunderlayerbymagnetronsputtering.Theeffectsofboththepost-annealingtemperatureandtheannealingtimeonthemicrostructureandmagneticpropertiesforthePr-Cofilmswerestudiedsystematically.Theas-depositedPr-Cothinfilmsaremostlyamorphousandtendtocrystallizeafterannealingattemperaturesabove600℃.Whentheannealingtimeisincreased,thefilmsshowacomplicatedstructurewithvariousphasesco-existing.Accordingly,theas-depositedfilmandlowtemperatureannealedfilmsaresoftmagnetsandfilmsannealedattemperaturesbeyond600℃tendtobehardmagnets.Whentheannealingtimeisincreasedfrom5minto2h,thefilmstransferfromhardmagnetstosoftagain.Thesampleannealedat600℃for10minshowsthelargestcoercivityof0.59T.

  • 标签: Pr 公司 COERCIVITY 磁性的记录
  • 简介:LiCoO2thinfilms,whichcanbeusedasacathodematerialinmicrobatteries,weredepositedusingradiofrequency(r.f.)magnetronsputteringsystemfromaLiCoO2targetandinanO2+Aratmosphere.ThefilmswerecharacterizedbyvariousmethodssuchasXRD,SEMandAFM.TheLiCoO2filmswereannealedinairat300,500,700and800℃respectively.Theeffectoftheannealingtemperatureonthestructure,thesurfacemorphologyandtheelectrochemicalpropertiesofthefilmswereinvestigated.TheLiCoO2thinfilmdepositedatroomtemperatureisamorphousandhassmallergrainsize.Withincreasingofannealingtemperature,thecrystallinityofthefilmsispromoted.Whentheannealingtemperatureincreasesto700℃,thefilmshaveaperfectcrystallineLiCoO2phase.TheLiCoO2thinfilmwithoutannealinghasnodischargeplateauandsmalldischargecapacity(about27μAh·cm-2μm).Thedischargecapacityincreaseswiththeincreasingofannealingtemperatureandreaches47μAh·cm-2μmforthefilmannealedwith700℃,whichalsoshowsthetypicaldischargeplateauof3.9V.ThecycleperformanceofLiCoO2thinfilmsofasgrownandannealedatdifferenttemperatureswerestudied.Inthecaseofthefilmwithoutthermaltreatment,thecapacityfadingismuchfasterthanthatofthefilmannealedatdifferenttemperature,showingabout40%capacitylossonlyafter25cycles.However,inthecaseofthefilmannealedat700℃,thecapacityreachestosteadystategraduallyandmaintainedconstantlywithcycling.After25timescycling,thedischargecapacityofthefilmannealedat700℃decreasestoabout36.9μAh·cm-2·μm,only0.8%capacitylosspercycle.

  • 标签: LICOO2 thin film ANNEALING temperature STRUCTURE
  • 简介:热变丑行为借助于扫描电子显微镜学(SEM)和单轴的热紧张被学习。流动应力上的变丑温度和紧张率的效果被评估,并且变丑机制被分析。压力紧张Ti-6Al-4V(TC4)合金表和TC4合金酒吧弄弯在的结果表演提高了温度有不同形式和规则。TC4的流动应力被紧张率和变丑温度控制。流动压力随高温度的增加减少。变丑机制在高温度区域和谷物边界以内展出动态恢复和再结晶特征在低温度滑动行为。

  • 标签: 高温变形行为 钛合金 扫描电子显微镜 金板 流动应力 高温合金
  • 简介:ThemicrostructuresandVickershardnessatroomtemperatureofarc-meltingprocessedintermetallicsofMo5Si3-MoSi2hypoeutecticalloyandhypereutecticalloyannealedat1200℃fordifferenttimewereinvestigated.LamellarstructureconsistedofMo5Si3(D8m)phaseandMoSi2(C11b)phasewasobservedinallthealloys.ForMo5Si3-MoSi2hypoeutecticalloy,thelamellarstructurewasfoundonlyafterannealinganddevelopedwellwithfinespacingontheorderofhundrednanometersafterannealingat1200℃for48h.Butwhentheannealingtimewasupto96h,thewell-developedlamellarstructurewasdestroyed.ForMo5Si3-MoSi2hypereutecticalloy,thelamellarstructurewasfoundbothbeforeandafterannealing.Howeverthevolumefractionandspacingofthelamellarstructuredidnotchangesignificantlybeforeandafterannealing.Theeffectsoftheformation,developmentanddestructionoflamellarstructureonVickershardnessofalloyswerealsoinvestigated.WhenMo5Si3-MoSi2hypoeutecticalloyannealedat1200℃for48h,theVickershardnesswasimprovedabout19%comparedwiththatwithoutannealingandformationoflamellarstructure.ThehighestVickershardnessofMo5Si3-MoSi2hypereutecticwasincreasingabout18%whenannealingat1200℃for48h.

  • 标签: 室温 钼-硅系统 层状结构 显微结构 维氏硬度 退火
  • 简介:CurieTemperatureofAmorphousFeSiBandFeWSiBAloysWangLingling,ZhaoLihua,HuWangyu(王玲玲)(赵立华)(胡望宇))DepartmentofPhysics,HunanUn...

  • 标签: CURIE TEMPERATURE FeSiB and FeWSiB ALLOYS
  • 简介:IsothermalcompressionofaTi-5.6Al-4.8Sn-2.0ZralloywasconductedonaThermecmaster-Zsimulatoratthedeformationtemperaturesrangingfrom960to1060°C,thestrainratesrangingfrom0.001to10.0s-1,andthemaximumheightreductionof70.0%.Inthetwo-phaseregionoftheTi-5.6Al-4.8Sn-2.0Zralloy,thevolumefractionofαphasedecreaseswithanincreaseindeformationtemperature,butthegrainsizehasaslightvariationwithdeformationtemperature.ThestrainrateaffectsbothmorphologiesandgrainsizeoftheαphaseintheisothermalcompressionoftheTi-5.6Al-4.8Sn-2.0Zralloy.Theoptimalheightreductionalsocontributestothesmallandwell-distributedαphaseintheisothermalcompressionofTi-5.6Al-4.8Sn-2.0Zralloy.

  • 标签: 微观结构演化 合金 TI 高温压缩 变形温度 等温压缩
  • 简介:Todevelopanewmagnesiumalloywithexcellentformabilityatroomtemperature,theeffectofY,Ce,andGdadditionontextureandstretchformabilityofMg–1.5Znalloyswascarriedout.TheresultshowsthatY,Ce,andGdadditioninMg–1.5Znalloyscaneffectivelyweakenandmodifythebasalplanetexture,characterizedbyTD-splittextureinwhichthepositionofbasalistitledfromnormaldirection(ND)towardtransversedirection(TD).WhenMg–1.5ZnalloywithGdadditionappearslowtextureintensityandTD-splittexture,wherethepositionofbasalpolesistiltedbyabout±35°fromNDtowardtoTD,thelargestErichsenvalueof7.0andtheelongationratereaches29.1%inTDdirection.However,YandCeadditioninMg–1.5Znalloyspromotealargenumberofsecondphaseparticles,whichcancelthecontributionoftheuniquebasaltexturetostretchformabilityandductility.

  • 标签: 可成形性 镁合金 GD CE 拉伸 RE系
  • 简介:Anisotropicpowderwaspreparedwithprecursor(NdDy)-(FeCoNbCu)-Bsinteredmagnetsbyhydrogendecrepitation,desorption,andsubsequentannealingtreatment.Thehydrogendesorptionwasperformedinmagneticfieldsof0,1,3,and5T.Theorientationoftetragonalphasegrainsofthepowderwasevaluatedfromthehysteresisloopsmeasuredbyextractionmagnetometer.Residualhydrogencontentofthepowderwasevaluatedbythermal-magneticanalysis.ThepowderwithHcj,Br,and(BH)maxof1138kA·m-1,1.029T,and172.5kJ·m-3,respectively,wasachievedundertheconditionofthemagneticfieldof3T.Magneticpropertiesofthepowder,especially,theremanenceofthepowder,areenhanceduponmagneticfields,whichisduetobetterorientationofpowderparticlesandlessresidualhydrogeninthepowderresultedfromthemagneticfieldduringthehydrogendesorptionprocess.

  • 标签: 各向异性 磁场 放氢 粉末制备 磁性 高温
  • 简介:Au/-Al2O3催化剂被免职降水方法为低集中白酒溪流(甲醇,乙醇,iso-propanol和n-propanol)的催化燃烧作好准备。催化剂被X光检查光电子描绘光谱学(XPS),X光检查diffractometry(XRD)和精力散X光检查微分析(版本)技术。XPS结果证明仅仅催化剂的表面上有Au0。XRD模式证明Au高度大概在-Al2O3上被驱散。为有2.0g/m3的集中的甲醇,乙醇,iso-propanol和n-propanol的完全的变换的温度是60,155,170和137?,分别地但是他们完全在60,220,260和217点被使矿物化进CO2和H2O吗?分别地在优化催化剂上。催化剂的活动在130h是稳定的。为催化甲醇消除的动力学跟随了伪--首先订表示为r=0.6528c0+0.084的反应2。明显的激活精力的价值是在反应温度的范围的54.7kJ/mol。

  • 标签: 光催化 催化性能 Γ-AL2O3 活性催化剂 X射线光电子能谱 X射线显微分析
  • 简介:TiO2/Au/TiO2多层的薄电影用dc(直接水流)在房间温度在聚合物底层被扔磁控管劈啪作响方法。由改变每层的厚度,TiO2/Au/TiO2多层的电影的光、电的性质能被定制适合不同应用。厚度和Au层的光性质和Au绝缘的接口的质量为Au绝缘的多层的薄电影的电、光的表演是批评的。在8nm的厚度,Au层形成有最低抵抗力和它的连续结构一定为高发射度薄。多层的栈能被优化有6的一个表电阻?在在在波长的680nm的超过80%的发射度的/sq.。当时,山峰发射度向长波长区域变二TiO2的厚度(上面、更低)层增加。当二部TiO2电影的电影厚度是45nm时,高发射度价值为全部可见轻波长区域被获得。

  • 标签: 复合涂层 磁电管反应溅射法 多层薄膜 光学特征 电学性质 二氧化钛