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196 个结果
  • 简介:Fe3Al金属间化合物具有良好的高温性能,在钢表面制备Fe3Al基金属间化合物涂层能有效提高基体在高温下的抗氧化、耐腐蚀、耐摩擦和抗冲蚀性能,其抗硫化性能甚至优于不锈钢。相比于同等功能的陶瓷涂层Fe3Al涂层与基体有更好的相容性。综述了Fe3Al基金属间化合物涂层的研究现状,介绍了涂层性能及影响因素,涂层制备的主要工艺方法和技术特点,主要包括热喷涂、堆焊、激光合成等。

  • 标签: 金属间化合物 FE3AL 涂层
  • 简介:1.IntroductionLightrareearthadditioncanremarkablyenhancetheservicelifeofFe-Cr-Alalloyforelectricalheatingelement,butitscontentinthealloymustbecontrolledbelowthelevelof0.1wt-%.Whenthecontentexceedsthat,theperformance

  • 标签: YTTRIUM ADDITION FE-CR-AL ALLOY EMBRITTLEMENT
  • 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
  • 简介:Theimplantedionrange,thedepthprofileandthefilmsttuctureoftheimplantedlayerwerestudied;thecarrierconcentrationandthemobilityweremeasured;theconductivitymechanismofthefilmimplantedFeintoAl2O3ceramicwasdiscussed.TheconclusionisthattheimplantedFe2+ionsmoveintoAl2O3latticeandreplaceAl3+toformsubs-titutionimpuritiessothattheionimplantedlat-tice,ascomparedwiththeoriginalone,presentsaneffectivenegativechargewhichformsanegativechargecenter.Avacancyisboundarroundit,andanacceptorisintroducedintheforbiddenband.

  • 标签: Al2O3 CERAMIC Fe2+ ion Surface resistivity
  • 简介:利用喷射沉积工艺制备Al-3.3Fe-10.7Si合金坯,经挤压制成试样。研究了合金组织、韧性及内耗行为,得出该合金在60-250℃温度范围产生的内耗峰,是由于晶界滑动弛豫引起的,弛豫过程激活能为172.2kJ/mol。在内耗峰位置晶界滑动消耗部分振动能,合金韧性在此处出现极大值。

  • 标签: 喷射沉积Al—3.3Fe-10.7Si合金 韧性 内耗
  • 简介:ThemicrostructureandcompositionofTiC-Al2O3/Fefunctionallygradedmaterials(FGM)preparedbyself-propagatinghightemperaturesynthesisandpseudo-hotisostaticpressing(SHS/PHIP)werestudied,andtheresistingthermalshockbehaviorswereanalyzed.TheresultsshowthatTiC-Al2O3/FeFGMhasgradedcompositiondistribution.Nocross-sectioncrackthroughthelayerswasfoundinthetestsofthermalshockandfatigue.

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  • 简介:TheevolutionofmicrostructureandmechanicalpropertiesofAl-0.4Cu-0.14Si-0.05Mg-0.2Fe(wt.%)alloys,micro-alloyedwithZr,TiandSc,wereinvestigated.Theadditionof0.2%ZrtobasealloyacceleratestheprecipitationofSi-richnano-phaseinα-Almatrix,whichplaysanimportantroleinimprovingthemechanicalpropertiesofanalloy.Thetensilestrengthincreasesfrom102MPaforthebasealloyto113MPafortheZr-modifiedalloy.Adding0.2%Zr+0.2%Titobasealloyeffectivelyrefinesa-AlgrainsizeandacceleratestheprecipitationofSiandCuelements,leadingtoheavysegregationatgrainboundary.Byfurtheradding0.2%SctoZr+Timodifiedalloy,thesegregationofSiandCuelementsissuppressedandmoreSiandCuprecipitatesappearedinα-Almatrix.AccompaniedwiththeformationofcoherentAl3Scphase,thetensilestrengthincreasesfrom108MPafortheZr+Timodifiedalloyto152MPafortheSc-modifiedalloy.DuetoexcellentthermalstabilityofAl3Scphase,theSc-modifiedalloyexhibitsobviousprecipitationhardeningbehaviorat350℃,andthetensilestrengthincreasesto203MPaafterholdingat350℃for200h.

  • 标签: Micro-alloying MICROSTRUCTURE Mechanical properties AL3SC GRAIN
  • 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:Aneffectivedispersion-strengtheningphaseinAl-8Fe-2Mo-2Zr-2Nd-0.7Ti-1.6SialloywasidentifiedtobeanagedprecipitatephasewithpossiblechemicalstoichiometryofAl20(Ti,Mo)2Ndandfcccrystalstructurewithao=1.455nm.ThestructurewasdeterminedtobeFm3mspacegroup.

  • 标签: high temperature AL ALLOY dispersion-strengthening phase
  • 简介:TheinteractionbetweenZn-AleutecticalloyandAl2O3p/6061Alcompositesinthevacuumfurnacewasinvestigated.Greatattentionhasbeenpaidtotheelementsdiffusion,themicrostructureandformationoftheinterfacebetweenZn-AIeutecticalloyandAl2O3p/6061Alcomposites.ExperimentalresultsshowthatZn-AleutecticalloyhasagoodwettingabilitytoAl2O3p/6061Alcompositesandthewettingangledecreaseswithincreasingthetemperatureinvacuum.Aftertheinteraction,aninteractionlayerformsbetweenZn-AIalloyandAl2O3p/6061Alcomposites.Thephasesintheinteractionlayermainlyconsistofα-Al(Zn),Al2O3andCuZn5resultedfromthediffusionofelementsfromtheZn-Alalloy.SeveralporositiesdistributeintheregionneartheinterfaceoftheZn-Alalloy/interactionlayer.TheamountofshrinkagevoidsintheinteractinglayerisrelevanttothepenetrationofZnelementintoAl2O3p/6061Alcompositeswhichisafunctionoftemperature.SoitisnecessarytolowerheatingtemperatureinordertolimittheZnpenetration.

  • 标签: 锌铝共晶合金 Al2O3p/6061Al化合物 湿润 界面微结构 焊接技术
  • 简介:美国密歇根理工大学的研究人员研究了一种以特殊涂层的形式内置传感器的外科植入体。在一切正常以及抵抗感染的情况下植入体均能发出信号。植入体由磁致弹性材料制成,

  • 标签: 植入体 涂层 内置传感器 研究人员 抗感染
  • 简介:用无溶剂复合PET和VMPET以及PET/AL这种两种基材都是高阻隔材料的结构,目前是个难题,尤其是满版白墨或黄墨的印刷膜复合,难度更大。

  • 标签: 无溶剂复合 PET AL 成熟 高阻隔材料 印刷
  • 简介:AresearchonkineticsofAlevaporationfromliquidU—Alalloyswasmadeinavacuuminductionmelting(VIM)furnaceat1673—1843K.TheevaporationrateofAlwasfoundtobefirstorderwithrespecttoAlcontentinthemelt.TheoverallmasstransfercoefficientofAlwasdeterminedanditwasfoundthattheevaporationrateofAlincreasedwithincreasingtemperatures.TheapparentactivationenergyofAlevaporationat1673-1843Kwas171.5kJmol-1.ThevalueofmasstransfercoefficientofAlintheliquidphasewasestimatedtobe3.77×10-6,7.41×10-6,and9.40×10-6ms-1at1673,1753,and1843K,respectively.Meanwhile,ratedeterminingstepswerediscussedanditwasconcludedthattheevaporationrateofAlismainlycontrolledbyliquidphasemasstransfer.

  • 标签: AL EVAPORATION KINETICS LIQUID U-Al alloys
  • 简介:我们集中于与Ni-Al金属间化合的混合物扔合金由的ligth重量的表面加强在原处改进非铁的扔的表面性质的燃烧反应部件。在我们的以前的工作,元素的Ni和艾尔粉末紧缩的绿色被SHS(自我繁殖的高温度合成)反应到形式Ni3Al金属间化合的化合物有熔融的艾尔合金并且同时的热的反应与艾尔扔结合了合金。但是象微小的裂缝和孔那样的一些缺点在反应协议被仍然是。我们因此使用了压力阻止热裂缝并且与液体艾尔合金充满毛孔由压榨扔过程。压缩艾尔合金与Ni3Al金属间化合的混合物结合了是sectioned并且由光显微镜学和扫描电子显微镜学(SEM)观察了。在结合的接口附近并且在反应协议形成的intermetallics的stoichiometric作文被散光谱学(版本)和电子探查的精力识别微分析(EPMA).Si富人层被艾尔的顺序的团结在结合的接口附近在艾尔合金方面上形成合金。在反应Ni3Al协议观察的孔与液体艾尔合金被充满。从熔融的艾尔合金的Si粒子在反应Ni3Al金属间化合的协议的毛孔被检测。扔合金和Ni3Al金属间化合的化合物的艾尔被把压力用于液体艾尔合金很很熟加入。

  • 标签: 压力 燃烧合成技术 铝合金 物理性能
  • 简介:ItwasshownbyTEMandX-rayanalysisthatNi3AlisthemainphaseoftheintermetallicsynthesizedundercompressionfromthepowdermixtureofNiwithAlalloyedbyB.TheNi3Bisasecondaryphase.ThevalueofthelatticeparameteroftheintermetallicNi3AlwithandwithoutBincreaseswhentheconcentrationofAlincreases.TheincreaseinAlconcentrationfrom23.5to25.0intheinitialpowdermixtureleadstodecreasingthesolubilityofBintheNi3Alphase.

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  • 简介:Al2O3/Al的三个系列把陶器的矩阵composites,命名矿泉,SPV和HP压成薄片,被不同方法制作。矿泉和SPV经由屏幕在空或真空中打印和随后的热处理用Al2O3片和艾尔泥浆被准备。HP样品被热压成为艾尔陪衬和Al2O3片的分层的栈。SEM和XRD被使用分析微观结构和夹层水晶阶段。弯曲力量,破裂坚韧和三个方法做的样品的破裂工作被测量并且比较。结果证明composites比Al2O3片有好一些的坚韧和更高的破裂工作。在三个方法做的样品之中,热压做的样品有最佳机械性能。排水量负担曲线和骨折机制被分析。

  • 标签: 陶瓷基复合材料 力学性能 制备 AL2O3/AL 叠层 惠普公司
  • 简介:PositronannihilationbehaviorshavebeenstudiedinthesinglephaseNd2Fe14BmagnetandthenanocompositeNd2Fe14B/α-Femagnet,preparedbymeltspinning.Theresultsshowedthatthenumberofvacancy-clusteratgrainboundariesincreaseswithincreasingannealingtemperatureforthebothtypesofmagnets.Theincreaseofthiskindofdefectcanimprovethecoercivityof

  • 标签: 正电子歼灭 单阶磁性 ND2FE14B 磁铁