学科分类
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78 个结果
  • 简介:FenanowirearraywithstrongshapeanisotropywasemployedasthesoftphaseinNd-Fe-Bbasednanocomposites.TheeffectsoftheFenanowiredistributiononmagneticpropertiesofthenanocompositeswereinvestigatedbymicromagneticsimulation.TheresultsindicatethattheshapeanisotropyofFewiresaddedinthesamedirectionastheuniaxialmagnetocrystallineanisotropyofthehardphasecannotincreasethecoercivityofthenanocomposite.Whenthenanowiresaredistributedperpendiculartotheeasyaxisofthehardphase,theshapeanisotropyofsoftphasecanretardthemomentsfromrotatingtothefullreverseddirection,leadingtoenhancedcoercivity.Inaddition,withincreasingthenanowirediameter,thecoercivityofthenanocompositedecreases,butthedipolarinteractionshowsdifferentrolesinmagneticreversalofnanocompositefordifferentdistributionsofnanowires.ThecurrentresultssuggestthatthecoercivityoftheNd2Fe14B/α-Fenanocompositecanbeenhancedbyintroducingthesoftmagneticnanowirearraywiththediameterlessthantheexchangelengthandwiththelongaxisalongthedirectionotherthantheeasyaxisofhardphase.

  • 标签: Nd2Fei4B/α-Fe NANOCOMPOSITE MICROMAGNETIC simulation FE NANOWIRES
  • 简介:PositronannihilationbehaviorshavebeenstudiedinthesinglephaseNd2Fe14BmagnetandthenanocompositeNd2Fe14B/α-Femagnet,preparedbymeltspinning.Theresultsshowedthatthenumberofvacancy-clusteratgrainboundariesincreaseswithincreasingannealingtemperatureforthebothtypesofmagnets.Theincreaseofthiskindofdefectcanimprovethecoercivityof

  • 标签: 正电子歼灭 单阶磁性 ND2FE14B 磁铁
  • 简介:1.IntroductionSofarthemicrostructureandcoercivityofSm(Co,Cu,Fe,Zr)7.4alloyhavebeenstudiedindetailbyvariousauthors.TheeffectofZr-richlaminarphasestructureonthehighcoecivityofalloyismoreattractive.Thechangesofmagnetic

  • 标签: HVEM OBSERVATION COERCIVITY ND-FE-B alloy
  • 简介:在甲醇-水体系中以NaBH4还原二价铁离子,得到了粒径为10~40nm的α-Fe金属粒子。在反应体系中加入右旋糖苷等分散剂以强化产物颗粒的分散。采用X射线衍射及透射电镜等测试方法对合成产物进行检测。结果表明,以湿化学还原法能合成纳米α-Fe金属粒子,但产物呈现网状团聚状态;右旋糖苷能很好地分散产物团聚体,在其作用下产物颗粒呈稳定的分散状态。

  • 标签: Α-FE 还原 合成 分散
  • 简介:ThebasestructureofinsituTiCP/Fecompositesfabricatedunderindustrialconditionwaschangedbydifferentheattreatments.Erosiveweartestswerecarriedoutandtheresultswerecomparedwiththatofwear-resistantwhitecastiron.TheresultssuggestthatthewearresistanceoftheinsituTiCp/Fecompositeishigherthanthatofwear-resistantwhitecastironunderthesanderosivewearcondition.Thewearmechanismofthewear-resistantwhitecastironwasacycleprocessthatbasesurfacewaswornandcarbideswereexposed,thencarbideswasbrokenandwearpitsappeared.WhilethewearmechanismofinsituTiCp/FecompositewasacycleprocessthatbasesurfacewaswornandTiCgrainswereexposedanddropped.ThewearresistanceofinsituTiCp/Fecompositewaslowerthanthatofwear-resistantwhitecastironundertheslurryerosivewearcondition.Undersuchcircumstance,thematerialwasnotonlyundergoneerosivewearbutalsoelectrochemistryerosionduetothecontactwithwaterinthemedium.Thewearbehaviourscanbeacombinationoftwokindsofwearandthesanderosivewearisworsethanslurryerosivewear.

  • 标签: 钛铁合金 腐蚀性表面 磨损装置 热处理
  • 简介:NitridingisemployedforthehardFeelectrodepositiontoproduceahard-facingandantiwearcoating.Itonlytakes1hforthehardFecoating,whichismuchshorterthannitridingtheFeandsteel.Theresultsshowedthatthenitridingcanincreasethemicrohardness,wearresistanceofthecoating,aswellasthebondingstrengthofthecoatingwiththesubstrate.Additionallyitcaneliminatethebrittleness,turntheinternalstressofthecoatingfromtensiontocompression.ThewearresistanceofthenitridedFecoatingis4.6timesashighasthatofCrcoating.ItissimpleandeconomictocombinehardFeelectroplatingandnitriding,whichisagoodtechnologyofthetribologicalsurfacemodification.

  • 标签:
  • 简介:1.IntroductionLightrareearthadditioncanremarkablyenhancetheservicelifeofFe-Cr-Alalloyforelectricalheatingelement,butitscontentinthealloymustbecontrolledbelowthelevelof0.1wt-%.Whenthecontentexceedsthat,theperformance

  • 标签: YTTRIUM ADDITION FE-CR-AL ALLOY EMBRITTLEMENT
  • 简介:介绍了Fe3Si的一些基本特性及Fe3Si薄膜的几种主要制备方法,重点介绍了分子束外延法中不同类型衬底、温度对Fe3Si薄膜形成的影响,并且分析了各种制备方法中的一些重要参数对薄膜结构及性质的影响。随着Fe3Si薄膜制备工艺的不断完善,Fe3Si薄膜将会成为一种性能优秀的自旋电子器件。

  • 标签: 薄膜制备 Fe3Si薄膜 自旋电子器件
  • 简介:Basedonthedifferenceofhydroxygroupconfigurationondifferentplanesofα-Fe2O3nanoparticles,usingthespecialadsorptionandcoordinationofphosphateonthe(001)planeofα-Fe2O3,well-crystallizedandwelldispersedα-Fe2O3nanodiskswithdiameterof150–200nmandthicknessof40–80nmweresynthesizedviaahydrothermalmethod.Themagneticpropertiesofsynthesizednanodiskswereinvestigated.Itwasfoundthatthenanodiskspossessedasaturationmagnetization(Ms)of0.38emu/g,aremanentmagnetization(Mr)of0.031emu/gandacoercivityof452.91Oeatroomtemperature.TheMrandcoercivityofsynthesizedα-Fe2O3nanodisksarehigherandtheMsislowerthanthoseofotherpreviouslyreportedα-Fe2O3nanostructures.

  • 标签: 纳米粒子 氧化铁 饱和磁化强度 制备 生长 封闭
  • 简介:Fe-Ni-Almixturesashot-pressingsinteringadditivetoTitaniumdiboride(TiB2)werestudied.ItisfoundthatliquidalloyformedunderhightemperaturehardlyhaseffectsonthedensificationbehaviorsofTiB2-independent.Fe-Ni-AladditivejustworksasfillerbetweenTiB2particlesanddoesnotchangetheTiB2-independentsinteringbehaviors.PressingmodehasagreateffectontheliquidflowingbetweenTiB2particles.Multiple-stepspressingmodewillgivemoretimeandspacefortheliquidflowingandimprovetherelativedensityofTiB2-Fe-Ni-Alcermet.

  • 标签: 烧结行为 金属陶瓷 添加剂 TiB2粒子 液体流动 二硼化钛