学科分类
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35 个结果
  • 简介:Au/TbMnO3/YBa2Cu3O7-xcapacitorswerefabricatedonSrTiO3substratesbypulselaserdepositiontechnique,ofwhichelectricpropertieswereinvestigatedinthetemperaturerangefrom25to300K.Bothcurrent-voltagecharacteristicsandjunctionresistanceswithbiasvoltagesshowedremarkabletemperaturedependence,inwhichobviousthermallyexcitedrelaxationprocesseswerefoundbetween150and200K.Atthetemperatureslowerthantheactivationprocess,theleakagecurrentsofthecapacitorswerestudied.Interestingly,athighelectricfield,themechanismoftheleakagewasPoole-Frenkelemission.However,atlowelectricfield,theconductionwasnotOhmic,andideallnJ∝E1/4characteristicswereobserved.Analysisshowedthatthepossibleoriginwasrelatedtotheinherentinhomogeneousnatureofactivationlesspercolatingtransport.

  • 标签: 低电场 电荷载体 运输 脉冲激光沉积技术 电影 低温
  • 简介:Strainageinginsteelwasfirstobservedduringthe19thcenturywhenthemaximumloadcarryingcapacityofatestpiecewasincreasedafterithadbeenretestedfollowingapreviousseriesoftestinginaplasticrange.Overthelastdecades,agreatdealofresearchhasbeenperformedtogaindeeperinsightsintothephenomenonofstrainageing.Thesynergisticdevelopmentoftheoreticalhypothesisandnewexperimentalevidenceshaspromotedtheunderstandingofthemechanismsunderlyingstrainageing.Thecontentofthispaperisorganizedintofourcomponents.First,wehavecomparedthemaintheoriesdevelopedinrecentyears.Second,wehavesummarizedthemetallurgicaleffectsonthestrainageingbehaviorobservedinexperiments.Moreover,wehavemadeanattempttocorrelatetheexperimentalresultsandtheabove-mentionedtheories.Third,wehaveproposedafeasiblesolutiontocontrolstrainageinginlowcarbonsteels.Finally,wehaveelaboratedthepotentialityoftheatomprobetechniqueinfacilitatingdirectcharacterizationofthedistributionofsoluteatoms.

  • 标签: 应变时效 低碳钢 实验证据 溶质原子 承载试验 最大负荷
  • 简介:Problemsencounteredintheproductionoflownickelausteniticstainlesssteelhavebeenstudied.Theseproblemsprimarilyincludethechangestothemicrostructureoftheslabduringtheheatingprocess,theformationandremovalofdeformation-inducedmartensiteduringcoldrolling,andtheeffectsoftheannealingprocessonthesurfaceoxidestructure.Areasonablemanufacturingprocesshasbeenproposedonthebasisoftheresearchresultsandhighqualitycold-rolledstripsoflownickelausteniticstainlesssteelhavebeenproduced.

  • 标签: 奥氏体不锈钢 生产 微观结构 冷轧带材 加热过程
  • 简介:Thedynamicandstaticrecrystallizationbehaviorsoftwinrollcastlowcarbonsteelstripwereinvestigatedwithanattempttoprovideguidingdeformationparametersfortheonlinehotrolling.Inordertoinvestigatedynamicrecrystallizationbehavior,ascaststripwasreheatedandsoakedwithaustenitegrainsizesimilartothewidthleveloftheascastcolumnarstructure.Tensiletestwasusedandthedeformationtemperatureisintherangeof900℃to1100℃andstrainratesare0.01s-1,0.1s-1,1s-1.Theactivationenergyandstressexponentweredeterminedas306kJ/moland4.69respectively.Theratioofcriticalstraintothepeakstrainis0.65,andthatofcriticalstresstothepeakstressis0.92.ThedependenceofthepeakstrainontheinitialgrainsizeandZener-HollomonparametersZisεp=9.1×10-4×D00.48Z0.13.Thekineticsofthedynamicrecrystallizationandrecrystallizedgrainsizewaspredictedusingmodelspublished.Theascastcoarseausteniteweredramaticallyrefinedaftercompletedynamicrecrystallization.Forstaticrecrystallization,thetensiletestwascarriedoutonGleeble-3500thermo-mechanicalsimulator.Thedeformationtemperatureisintherangeof800℃to1200℃withstrainrate0.01s-1to1s-1.Theprestrainisfixedat0.04to0.12andtheinter-hitdelaytimevariesfrom1sto3000s.TheactivationenergyandAvramiexponentofstaticrecrystallizationweredeterminedas241kJ/moland0.54respectively.Akineticsmodelwasproposedtodescribethestaticrecrystallizationkinetics.Thepredictedresultswereingoodagreementwiththeexperimentalresults.

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  • 简介:(Ba0.66Sr0.33)Mg0.8Al11.47O19:Tm0.013+(BSMA:Tm3+)phosphorwassynthesizedbysolid-statereactions.ThesamplewascharacterizedbyX-raydiffraction(XRD),scanningelectronicmicroscope(SEM),vacuumultraviolet(VUV)spectra,ultraviolet(UV)spectraandFT-IRspectrum.XRDpatternrevealsthatBSMA:Tm3+hasthesamestructureasBaAl12O19phase.SEMimageillustratesthatthephosphorhasthehexagonalshapeanddeepslicestructure.VUVandUVemissionspectraat20,50and100Kshowthatthelowtemperatureluminescenceintensitiesbecomeweakgraduallywiththeincreasingofthetemperatureunder147and254nmexcitation.Thestrongbroadbandpeaksataround357and397nmandthepeakat516nmunder147nmexcitationallcorrespondtothecharacteristictransitionsofTm3+ions.However,underUV(254nm)excitation,themainpeakbecomes530nmwhichhasveryhighlineintensity,andthepeaksatabout362and403nmareveryweak.Theexcitationspectrumat20Kshowsthattherearethreeabsorptionpeaksataround153,186and193nmwhen516nmemissionismonitored.Theabsorptionpeaksof[AlO4],[AlO6]andAl-OcanbeobservedinFT-IRspectrum.

  • 标签: VACUUM ULTRAVIOLET low temperature LUMINESCENCE Tm3+
  • 简介:Fluorineinmoldpowderisknownasharmfultohumanhealthandtheenvironment.Beingtheadvocateofgreenproduction,Baosteeldevelopedanenvironmentallyfriendlymoldpowderwithoutfluorine.Themainproblemoffluorine-freefluxfilmissmallheatresistanceandthustheheattransferintensityofthemoldistoolarge,whichtosomeextenthinderstheincreaseofthecastingspeed.Withtheheatflowsimulationequipment,controllingprecipitationofcrystalinfluxandsolidificationtemperatureproperly,fluorine-freemoldpowderforlowcarbonsteel,whichsubstitutesFwithB2O3,wassuccessfullydevelopedandappliedinindustrialproduction.Theproductionresultsshowthat,byusingboronicfluorine-freemoldpowder,theboronincrementinmoltensteelislessthan1.3ppmforconventionalaluminiumkilledlowcarbonsteel.

  • 标签: 结晶器保护渣 无氟保护渣 低碳钢 开发 应用 绿色生产
  • 简介:ThecorrosionbehaviorofaweatheringsteelSPA-Candtwoacidresistancesteels(S-TEN1andND)insulfuricacidsolutionwasinvestigatedbyusingpotentiodynamicpolarizationandweightlossmeasurementtechniques.Bothpotentiodynamicpolarizationandweightlossmeasurementtestsindicatedthatcorrosionresistanceofthesethreealloysteelswasasfollows:ND≈S-TEN1>SPA-C.Surfaceanalysisofthecorrodedsamplesconductedaftertheimmersiontestindicatedthattwolayerswereformedonthesubstrates,withtheouterlayercomprisingFeSO_4·H_2Oandtheinnerlayermainlycomprisingironoxides.TheadditionofCu,Cr,andSbrefinedthecorrosionproductsandimprovedtheadhesionabilitybetweentherustlayerandthesubstrate.

  • 标签: 腐蚀行为 硫酸溶液 低合金钢 动电位极化 硫酸亚铁 耐腐蚀性能
  • 简介:Thereliabilityofsteelweldsbecomesmorecriticalissuewithincreasingsteelstrength,becausebrittlephasesaremorelikelytoformintheweldmetalsandheat-affectedzone(HAZ)andtherebythetoughnessandductilityoftheweldsaredegraded.Therefore,refinementofmicrostructureandminimizationofthebrittlephasesarenecessarytoimprovethereliabilityofthehigh-strengthsteelwelds.Inthispresentation,microstructureformationthatcontrolsthetoughnessofweldmetalsandHAZinhigh-strengthlow-alloy(HSLA)steelweldsisreviewedandpossibleroutestotheimprovementoftheweldmicrostructureandweldtoughnessarediscussed.

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  • 简介:Inordertomeetthedemandsofservicelifeandthesyntheticalperformance/priceratioofstainlesssteelinthesolarwaterheaterindustry,thelowmolybdenumultra-pureferriticstainlesssteel(FSS)B445J1MwasdevelopedatBaosteel.Inthisstudy,comparativestudieswerecarriedoutonthemechanicalproperties,theformabilityandthecorrosionresistanceofB445J1M,304and444,andtheadvantagesandapplicationfieldsofB445J1Mweresummarized.

  • 标签: 太阳能热水器行业 铁素体不锈钢 高纯 性能/价格比 使用寿命
  • 简介:Theproductionindexesweredeterioratedduetoqualitycoke,UtilizationFactor2.0t/m3·d,PCI100kg/T,AccordingtoAnalysistheMechanismofProductionoflowhotstrengthcokequalityonBlastFurnaceSmooth,ThecokecoldstrengthretainedM10<6.3overalongperiodoftimeinordertoinsurecokegranularityandpermeabilityindexincohesivezone;Aad<12andgranularitytranquilizationisusefulBFproduction.ThePCIprotectcokehotstrengthbyhighratebituminouscoals;highrateH2inBFgasbatecokedemolish.blastfurnaceoperation,onmonitoringandoperationBF,tranquilizationtheBLASTFURNACEtemperature,PTcontrolsparameterareaisabout1500℃;strengthenmanagementofpermeabilityindex,improveTop-pressureforBlastFurnace,StrengtheningtheManagementoftheRawMaterialsandFuel,logicalrateofsinterLeveloffabout70%toimproveMetallurgicalPropertiesofBurdens.ParametersofwindhavebeenadoptedAbout10000-11000kg·m/s;,theoreticalflametemperatureinablastfurnacehavebeenadjustedareaisabout2050-2200℃;thetemperaturedirectionaboutcopperstavemanagementestablishedact;accordingtothismeasures,AccordingtoImprovementCenterGasFlowInstabilityinthefirstplace,thegasflowdistributionturnstothereasonablestate.Strengthenfurnacecasthouseoperationect,UtilizationFactorimprove2.2t/m3·d,PCI130kg/T.ColdandhotstatestrengthindexesofcokeonBFproductionwereinstability.AccordingtooptimizetheOperatingParameteinspecificallyeconomytechnologyindexesconduction,theBFcondictioncankeepingsteadyandsmooth.

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  • 简介:A0.06%Clowcarbonsteelwasdeformedintorsionoverthetemperaturerange877-917℃ina2%H2-Argasatmosphere.Strainsof0.25-5.0wereappliedatstrainratesofε=0.04s-1andε=0.4s-1tostudytheformationofferritebydynamictransformation(DT)attemperaturesabovetheAe3.ThecriticalstrainforferriteformationbyDTwasaboutε=0.2anditsvolumefractionincreasedwithstrainanddecreasedwithtemperatureabovetheAe3.Averageferritegrainsizesof1.5μmto5μmwereproduced,whichdecreasedwithstrainrate.Atthelowerstrainrate(ε=0.04s-1)reversetransformation(RT)tookplaceduringdeformationonceanincubationtimeofabout40s,wasexceeded.Anincreaseinstrainratefromε=0.04s-1toε=0.4s-1arrestedRTduringtestingatalltemperaturesasthetotaltesttimesdidnotexceed13s.ThepresentworkshowsthatDTisfavoredathigherstrainratesbyincreasingthedrivingforce(i.e.storedenergy)andbysuppressingRT.

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  • 简介:Thisarticleistrytoexplainoranalyzethekeytechnologiesofcontrollingthesurfacequalityoflowcarbonsteelascaststripthroughinvestigationofinterfaceheattransferbetweensolidifiedshellandliquidsteel.Theoneofthekeytechnologiesofcontrollingsurfacequalityoflowcarbonsteelascaststripisthroughthecastingrollsurfacetextureinordertoachievethehomogeneoussolidificationonthecastingroll.Anotheristhroughformingathinfilmonthecastingrollsurfaceinordertoachieveabalancebetweenrapidsolidificationandhomogeneoussolidification.Thisfilmformedbetweenthetwinrollandthemoltensteelcanbecontrolledbyadjustingthechemicalcompositionandinclusioninliquidsteelthroughcontrollingtheamountofall[O]andfree[O].

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  • 简介:Alloyingelements,suchassiliconandmanganese,haveamajorimpactonthephasetransformationpointofsteel.Specifically,manganeseisanelementfortheexpansionandstabilityoftheausteniteregion,whilesiliconcanexpandandstabilizetheferriteregion.Phasetransformationoccursduringthehotrollingprocessforthesteelwithcertainsiliconcontent,whichleadstogreatchangesofthedeformationresistance,therebyaffectingtherollingstability.Consequently,abetterunderstandingofphasetransformationintherollingprocesswillcontributetotheenhancementofproductquality.Inthispaper,theon-linerollingdatawereprocessedbymeansoftheinversecalculationmethod.Inthismethod,thesteeldeformationresistancewithvarioussiliconandmanganesecontentswasobtainedandanalyzedtodeterminethedeformationbehaviorofthesteel,whichcanhelpimprovetheon-linecontrolmodelandenhancethesteelquality.

  • 标签: 低碳钢 滚动式 变形过程 轧制稳定性 温度 合金元素
  • 简介:Thetensilebehaviorandpropertiesofcoldformedlow-carbonmicroalloyedsteelwithitsmicrostructureofallferriteandpearlite(F+P)wereinvestigated.Bendingandflatteningdeformationswerecarriedoutinthelaboratoryonhot-rolledsheetsinordertosimulatethecoldformingprocessofsteelsheetsduringpipefabricationandsamplingofhighfrequencystraightbeadweldingpipes.Acomparisonofthetensilebehaviorandpropertiesofthematerialmadebeforeandaftercoldformingindicatesthatcolddeformationaltersthetensilebehaviorandpropertiesofthematerialtoacertaindegreedependingonthemannerofthecolddeformationandthedegree.TheresearchontheBauschingereffectindicatesthatforthesteelsinvestigated,whentheplasticstrainissmall,thebackstressincreasesrapidlywiththeincreaseoftheplasticstrainandthenrapidlytendstosaturation.ThefiniteelementanalysisindicatesthatthechangeinthepropertiesofthesteelsheetsduetocoldformingisaresultoftheBauschingereffectandworkhardening.Themechanismofthechangeinthepropertiesisalsogiveninthisstudy.

  • 标签: 拉伸行为 钢性能 微合金 低碳 材料性能 塑性应变
  • 简介:Themicrostructuralcharacteristicsandformabilityattheedgesoflowcarbonpickledsteelsheetshavebeeninvestigatedbasedonthegenerationofearingandcrackingdefectswhiledrawing.Themicrostructureoftheedgefeaturescoarsegrainsandmixedsizedgrains.Thestrengthofthesheetedgeisslightlylowerthanthatatthecenter.Besides,theformabilityisobviouslyworsened.Theplasticstrainratiosalongthelongitudinalandtransverseorientationsare0.31and0.6,respectively,withdistinctanisotropy.Theplasticstrainratioattheedgeisobviouslylowerthanthatatthemiddleofthesteelsheet.Theobservedmicrostructuralcharacteristicsandmechanicalpropertiesattheedgeofthesteelsheetcanbeattributedtothelowerrollingtemperatureinthetwo-phaseregionofpro-eutectoidferriteandaustenite.Thesedifferencesinmicrostructureandmechanicalpropertiesattheedgeofthesteelsheetleadtothegenerationofearingandcrackingdefectswhiledrawing.Themicrostructureandmechanicalpropertiesattheedgeoflowcarbonpickledsteelsheetscanbeimprovedviatheoptimizationoftherollingprocessandtheadjustmentofchemicalcomposition.

  • 标签: 微观结构特征 冲压成形性 显微组织 低碳钢 钢板 塑性应变比
  • 简介:Abstract:Inordertounderstandtheeffectofthesolidificationstructureontheformabilityofultralowcarbonferriticstainlesssteel(FSS),thisworkstudiestheridgingphenomenonandthedeep-drawingpropertyindetailandtheresearchmethodwasX-raydiffraction(XRD)andscanningelectronmicroscope(SEM)technique.Theresultshowsthatthecolumnargrainspecimenhadahigherridgingheightthantheequiaxedgrainspecimen,whichwasmainlyattributedtotheformationofgraincoloniesinthecolumnargrainspecimen.Afterfinalrecrystallizationannealing,theequiaxedgrainspecimenobtainedahigh-intensityγ-fibertextureandanexcellentdeep-drawingproperty.

  • 标签: 铁素体不锈钢 深冲性能 凝固结构 超低碳 起垄 扫描电子显微镜
  • 简介:ThemorphologiesevolutionofvarioustypesofinclusionsinTi-IFsteelwereobservedbyaspecialdeptherosionmethod,andtheformationandevolutionprocesswerediscussed.TheresultsshowedthatthemaininclusionswereFeO·xMnObeforeAldeoxidizationandtheratioofintegratedoxygenandfreeoxygenwasinrangedof0.3to0.4.Inpresentstudy,themaineffectfactorsonthemorphologiesofAl2O3inclusionswere[Al]/[O]Free(solublealuminumdividefreeoxygen)andinitialfreeoxygen;clusterAl2O3wasformedeasilywithhighfreeoxygen([O]Free)andlow[Al]/[O](blew3inpresentstudy).Otherwise,thedendriticAl2O3wasformed;coral-likeAl2O3wasthemixtureofthedendriteAl2O3andsphericalAl2O3.SomeAl2O3·TiOxinclusionsappearedbecauseahigh[Ti]concentrationregionexistedaround70TiFe(containing70percenttitanium)particlesafter70TiFeaddition.ThemaximumsizesofAl2O3reached800μmwhen3minaluminumwasadded;asthetimepast,thelargesizeAl2O3decreasedsignificantly;themaximumsizeofAl2O3wasblew100μmand50μmincalmingsampleandtundishsamplerespectively.

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  • 简介:Inthepresentwork,themicrostructure,texture,andmechanicalpropertiesofacold-rolledTi-IFsteel,afterannealingatdifferentheatingrates,havebeeninvestigated.Theresultsrevealthatthemeangrainsizeisgraduallyrefinedfrom19.2to16.3μmastheheatingrateincreasesfrom4to50℃/s,butrefinedonlyslightlyatheatingratesofover50℃/s.Therecrystallizationmicrostructurehasastrongtexture,whichisaresultofthesharpeningofthefavorable{111}//ND(normaldirection)texturecomponentsorγ-fiber.Withincreasingheatingrates,thepeakvalueoff(g)ofγ-fiberdecreasesfrom17to9.Theyieldandtensilestrengthsincreasegraduallyastheheatingrateincreasesfrom4to50℃/s,butremainalmostunchangedatheatingratesofmorethan50℃/s.Thetotalelongationanduniformelongationincreasegraduallyastheheatingrateincreasesfrom4to100℃/s,butdecreasesslowlyforheatingrateshigherthan100℃/s.Astheheatingrateincreasesfrom4to100℃/s,theplasticstrainratioofthesteeldecreasesfrom2.8to2.2;however,itincreasesto2.9forheatingratesabove100℃/s.Thestrainhardeningexponentremainsunchangedat0.27inallannealingcycles.

  • 标签: 升温速率 超低碳钢 再结晶 组织与性能 加热速率 均匀延伸率
  • 简介:Abstract:Theeffectofstabilizingelements,suchasNbandTi,onthemicrostmctureandpropertiesoflowcarbonferriticstainlesssteel(FSS)hasbeeninvestigated.TheresultsoftheThermo-calcsimulationhaveshownthattheinterstitialelements,suchasCandN,maybecompletelystabilizedbytheadditionofNbandTi.WiththeincreaseofNbandTicontents,thea+γtwophasesgraduallytransfertoasingleα-phaseunderahightemperaturecondition,andthecontentofthecarbideM_(23)C_6graduallydecreases.ThemicrostructurehasindicatedthatthecombinedadditionofNbandTicanpromotetherecrystallizationofthebandstructureandformmoreuniformequiaxedgrains.Also,withtheincreaseofNbandTicontents,theelongation,ther-valueandthecorrosionresistanceofcold-rolledandannealedsheetsareimprovedprominently.IncomparisonwiththeeffectofTi,theadditionofNbismorebeneficialtotheincreaseofr-valueandthecorrosionresistance.

  • 标签: 铁素体不锈钢 耐腐蚀性能 微观结构 钛元素 低碳 稳定
  • 简介:AseriesofMn-basedcatalysts,MnOx,MnOx-CeO2,Pd-Mn-Ce,MnOx/ACwereprepared.AndtheirperformancesforNOlow-temperatureSCRwereinvestigatedinthisstudy.TheNOconversionisabout90%at100℃onMnOx-CeO2andalmostallNOcanbeconvertedat120℃.SimilarresultsarealsoobservedinthetestsonMnOx-CeO2/AC.Theexcellentlow-temperaturecatalyticactivityofmodifiedMn-basedcatalysts,whichmaybemainlyduetotheoxygenstoragefunctionofCeO2,canimprovetheoxygenflowonthecatalystssurface.ThentheoxidationofNOtoNO2isaccelerated,whichisthekeystepofNOSCR.

  • 标签: LOW-TEMPERATURE SELECTIVE CATALYTIC reduction (SCR) NO