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  • 简介:Thepapermainlydiscussedtheinclusionsandthepurityofmoltensteelandcontinuouscastingslabintapping,argon-bubbling,LFrefining,VDvacuumdegassingandcontinuouscastingtundishprocessesduringthesteelmaking.Atthesametime,theimprovementmeasuresofsmeltingprocesswereindicated.Si-Al-BaalloyandCa-Sideoxidationeventuallywereadoptedin120tconverter.Theamountofthetappingwasabout135t.AfterfeedingAlwireandaddingpremeltedslaginfurnace,pickedupthesampleafterthebottomargon-bubblingwhichhadbeendoneforover5minutes.Thelime,fluorite,calciumcarbideandAlpowderswereusedtoproducewhiteslaginLF.Thenthealloycompositionswereadjusted.FeedingCawireafterthetreatment,andtookoutover5minutes’softconverting.TheVDvacuumdegassingshouldbekeptfor15minutesbellow1.5torr.Afterthat,Cawirecouldbefed.Finally,castingtheslabintothesizeof260mm×2280mm.Theresearchshowed:(1)Inconverterprocedure,thedephosphorizationeffectturnedoutgoodwhentheratioofdephosphorizationwas88.2%.Thefinaloxygenandnitrogencontentssatisfiedthedemand,andtheeffectsofthefinalcontrolandbottom-blowingweregood.(2)DuringtheLFrefiningprocess,thenitrogenseldomadded.Itshowedtheexcellentsealingeffectandtheoptimizationoftechniquesonoperatingwhichhadreachedthedomesticleadinglevel.(3)AftertheVDvacuumdegassingprocess,theSi,Mn,P,O,Ncontentswerealmoststeady.Thesulphurcontentkeptdecreasingto0.003%andthe[H]contentwas1.9ppm.Theeffectofthevacuumdegassingprocesswasgood.(4)Theoxygencontentwascontrolledat11ppminthecontinuouscastingprocess,andthenitrogencontenthadincreasedto53ppmwiththeΔ[N]28ppm.Therefore,inordertopreventthemoltensteelfromreoxidization,theprotectionofthecontinuouscastingshouldbecontrolledrigorously.(5)TheinclusionsthatexistedbeforetheLFrefiningprocessweremostlyMnO-Al2O3-SiO3compositeinclusions

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  • 简介:本文联系陶渊明的生平及思想,指出了《五柳先生传》中的五柳先生即作者本人心目中的理想人物,是按照自己的思想情探塑造出来的人物形象。并且从艺术的角度分析了《五柳先生传》的两大特点,即结构严谨和语言精美。

  • 标签: 陶渊明 作品 艺术特色 《五柳先生传》
  • 简介:Inordertoresearchthetemperaturedistributionandmechanicaldeformationofslabbulgingduringhighspeedcontinuouscasting,mathematicalmodelshavebeendevelopedtoanalyzethethermalandmechanicalbehavioroftheslab.Thethermalhistoryoftheslabhasbeenpredictedbyatwo-dimensionaltransientfiniteelementheattransfermodel,whoseresultsserveastheinputtothestressmodel.Thestressmodelhasbeenformulatedforatwo-dimensionallongitudinalplane.Inthiscase,themaximumtensilestrainduringthebulgingprocessislocatedatthesolidificationfrontjustpastthetopoftheupstreamroll,whichmaycontributetocrackformation.Themaximumtensilestressesarelocatedatthecoldsurfaceinthemiddleofthetwoback-uprolls,justatthepointofthemaximumbulging.Stressesnearthesolidificationfrontaresmallbecauseofthehightemperatureswhichproducelowerelasticmodulusvalues.Finally,theeffectofthecastingspeedonthebulgingdeformationisdiscussed.

  • 标签: 高速连铸 应力模型 最大拉伸应力 温度分布 连铸板坯 机械变形
  • 简介:ThechemicalstateofgrainboundarycosegregationofCeandPinFe-P-CealloysystemwasstudiedbymeansofAugerElectronSpectroscopy(AES).TheAugerpeaksofCesegregatedatgrainboundariesarefoundwithintherangeof60~180eV.BycomparingwiththeAugerspectraoftheFe-Ce-Pintermetalliccompound,itissupposedthatthereisatwo-dimensionalinterfacialphaseatgrainboundarieswithCeandPcosegregationwhichissimilartothestructureoftheFe-Ce-Pcompound.

  • 标签: GRAIN BOUNDARY cosegregation CERIUM PHOSPHORUS AES
  • 简介:Theprocessesoffineironorereducedinfluidizedbedhavebeenreviewedinthispaper,thesuperioritiesandlimitationsoftheprocessesofdirectreduction,pre-reductioninfluidizedbedhavealsobeencomprehensivelyanalysed,whichmatcheswithbathsmeltingfurnaceorcokebedtypefurnace.Theanalysishasalsobeenmadeonseveralcontroversialtopics,andthegasuseratiohasbeenpointouttobethekeyofthecompetitionofthereductionprocessinfluidizedbed.Thesuitabilitywithfinalreductionfurnaceisalsoimportanttotheenergysavinginthewholesmeltingreductionprocess.

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  • 简介:Hot-rolledgalvanizedsteelsheetismadefromhot-rolledpickledsheetbycontinuoushot-dipgalvanizingprocess.Withoutthecold-rollingprocess,itgreatlyreducestheoperatingcostsandsavesinvestmentforshorterprocessandlowerenergyconsumption.Theeconomicadvantageisobvious.Thecharacteristicsofhigh-yieldandlowcostwillgreatlyenhancethecompetitivenessofenterprisesinthemarket.Therearebigdifferencesbetweenthesubstratesofhot-rolledgalvanizedsteelsheetandcold-rolledgalvanizedsteelsheetinsurfaceroughness,chemicalelements,andsurfacedefects.Thesefactorsdirectlyaffectonthequalityofgalvanizedsheet.Picklingprocessisusedtoremovetheoxidelayerwhichisformedonthesurfacesofhot-rolledsteelsheet.Thesurfacesmustbethoroughlycleanedfortheoxidelayerwillseriouslyaffecttheadhesionofgalvanizedcoating.Residualimpurities,Carbonconcentratingandotherproblemsmustnotbecausedduringpicklingaswell.Therefore,thequalityofgalvanizingdependsonthequalityofpickledsheetsurfaces.ExperimentalmethodssuchasAES,XPS,SEM,OMareemployedduringtheresearchfordetailedanalysisontheeffectsofhot-rolledplatesandhotpicklingplatesonthequalityofhot-rolledgalvanizedproducts.

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  • 简介:TheoverallreactionwasdeterminedonthebasisofthedissociationconstantofTBAandtheratiooftheligandtotherareearthioninthecomplex.Theratelaw,rateconstantsandacitivitionenergiesforthereactionofLa3+,Gd3+andHo3+withTBAwerestudied.ItisshowninthestudythatprerequisitesforperformingdifferentialrateanalysisforbinaryrareearthswithTBAarethatthepseudo-first-orderparallelreactionmechanismshouldbeconformedwith,nomultinuclearcomplexwouldbeformedandtheco-colorationeffectscouldbeneglected.

  • 标签: RE La Gd Ho KINETICS ANALYSIS
  • 简介:Thisstudydiscussesthekeyfactorslimitingtherateofpulverizedcoalinjection(PCI)inblastfurnaces(BF),whilethepracticeandexperiencesofBaosteel'sBFproductionwithhighproductivityandlowfuelconsumptionarealsoanalyzed.AmethodologybasedontechnologicalanalysisforachievingareasonablePCIrateisproposed.ItisemphasizedthathighBFproductivityshouldberealizedatthemaximumboshgasindexbasedonahigherblasttemperatureandtheexcellentqualityofrawmaterials,aswellasahighblastvolumeandmeltingstrength.

  • 标签: 鼓风炉熔炼 PCI 炼钢技术 温度条件
  • 简介:Baosteeldevelopedadigitalautomaticanalysistechniqueformaceralspecificationin2002.Thisanalysissystemcombinesdigitalimageprocessing,graphics,databases,expertsystems,artificialintelligenceandotheradvancedtechnologies.After6yearsofapplicationincokeproduction,thesystemproveditselfsuccessfulincoalqualitytestingandcoalblendingguidanceonmaceral.However,duringthislongprocess,someinadequacieswerefoundthatimpactedtheprecisionandaccuracyoftheanalysis.So,in2008Baosteelbegantoworkonimprovingthecoalmaceralanalysissystem.Theimprovementsincludedthefollowing:furtherupgradingandenhancingtheanalysisperformanceofmicroscopicimages;extendingthegraylevelstoincreasethereflectancemeasurementaccuracy64times;changingthefocusmethodandeffectivelyeliminatingtheinterferenceofhalo.Inaddition,animprovedimagerecognitionmethodwasadoptedtomaketheextractionofvitrinitemoreaccurateandanewmodelofcoalconstituentalgorithmwasaddedwhichcanaccuratelydeterminethecompositionofmaceral(exinite,vitrinite,inertinite).Sincetheseimprovementswerecompleted,thesystemhasachievedhigherautomation,speedandaccuracy,collectedmoreinformationandperformedmoreaccuratemaceralanalysisforcokeproduction.Meanwhile,theimprovedsystemhasprovidedareliableanalyticalbasisforthefurtherstudyontherelationshipbetweencokequalityandcoalblending.

  • 标签: 自动分析技术 显微组分 宝钢 规格 数字图像处理 专家系统
  • 简介:Increasingproductioncapacityandoperatingrate,reducingfuelratesandcostsofhotmetal(HM)aretheurgenttasksfortheCOREXprocess.Inthisstudy,thevariousfactorsonthefuelconsumptionofCOREXareresearchedfromthetheoreticalanalysisbasedonthecalculationsofmaterialbalancesandheatbalances.CombinedwiththeproductionperformancesandpracticesofCOREX-2000(Saldanha,India)andCOREX-3000(Baosteel),thetechnicalmeasuresofreducingthefuelrateareanalyzedandthewayforwardoftechnicalinnovationisaddressedanddiscussedwiththestandpointoftheCOREXprocessimprovement.

  • 标签: COREX工艺 油率 燃料消耗 技术创新 热平衡计算 生产能力
  • 简介:MaterialFlowAnalysis(MFA)isacrucialinstrumentforsustainabledevelopmentandcreatingindustrialecologysystem.MFAstudiescouldbalanceandanalyzethesources,flows,andconsumesofspecificmaterialsorsubstances.TheresultsofMFAstudiescouldsupportthestrategiesordecisionsmakingforenergy,resource,andwastemanagement,especiallyachievingsustainableresourcemanagement.AtCSC,thedynamicsimulatingsoftware,STELLA,isusedtodevelopaMFAmodelforscenarioanalysis.CSCalsousesthefreewareSTAN2.0asatoolforvisualizingandsimulatingmaterialflowsandstocks.CasestudiesofgreenhousegasesMFAforintegratedsteelworksareconducted.Theresultsshowedthatthecarboncontentofhot-metalisanimportanthiddenflowforbalanceanalysis,andthedifferentGHGemissionscenariosandmitigationactionscenariosareassessed.Inaddition,theIron-makingGHGI/OMFAModel,basedonworldsteelGlobalSteelSectorApproach(GSSA),isdevelopedforcalculatingtheCO2andenergyintensityofcokemaking,sintering,andBFprocesses.ThisMFAmodelwasusedtoanalyzetheCO2reductionpotentialforiron-makingprocess.ThecasesconductedforMFAapplicationsatCSCweresuchasgreenhousegas,zinc,etc.Inthefuture,CSCisgoingtodevelopa'CSCEnvironmentManagementandDecisionSupportingSystem'whichcombineMFA,LCA(lifecycleassessment),andenvironmentriskassessment.Thissupportingsystemexpectstopromotingenergyefficiencyandbestresourceuse,supportingenvironmentpolicymaking,creatingenvironmentalinformationvalue,etc.

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  • 简介:Inthispaper,themechanicsofstripedgecracksanditspropagationhasbeenstudied,andtheeffectsofstripedgedropandstressintensityfactor(SIF)onedgecrackdefectionsduringcoldrollingofthinstriphavebeendiscussed.Anexperimentalinvestigationwaspresentedintotheeffectofstripedgedroponedgecracksduringcoldrollingofthinstrip.Theedgecrackincreasessignificantlyduetomoreinhomogeneousdeformationandworkhardeningatthestripedge.Theeffectivestressintensityfactorrangeisimportantasitrepresentsthemajorphysicalcauseofthecrackpropagation.TheefficiencyandreliabilityoftheSIFanalyticalmodelhasbeendemonstratedinthestudy.Theproposedmethodforpredictingstripedgecrackishelpfulinproducingdefect-freeproductsandprovidinganunderstandingofthemechanicsofedgecrackpropagationincoldrollingofthinstrip.

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  • 简介:309Lisakindofausteniticstainlesssteel.Thispaperdiscusses309L,whichwassmeltedandrolledinalab.Itsmicrostructuralcharacteristicsinstatesofas-cast,hot-rolling,cold-rollingandsolidsolutionwereinvestigatedrespectivelybyopticalmicroscope(OM).Itisfoundthat309Liscomposedofausteniteandresidualδ-ferriteundertheseconditions,andtheδ-ferritecannotbeeliminatedeasilybyheat-treatment.Itshotplasticityanddeformationresistancewereinvestigatedinaseriesofheatsim...

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  • 简介:Inthisstudy,a600MPahot-rolledcorrosion-resistantsteelplateproducedbyaspecificcompanyisinvestigated.Edgejaggeddefectsandedgesurfacedefectsgeneratedonbothsidesofthestripduringproductionarecharacterizedandanalyzed.Theresultsindicatethatthedistributionofreoxidationgranulesislocatedunderneaththesurfacepeelandthatcopper-containinggranulesdiffusealongaustenitegrainboundaries.Thisphenomenoncombinedwiththechemicalcompositionandproductionparametersofastripindicatethatcopperbrittlenessleadstoedgejaggeddefects.However,thesurfacedefectsshouldbeattributedtoinherentdefectsonthesurfaceofthestrip.Measuresthatpreventsurfaceoxidationandcoppersegregationatgrainboundarieswouldlikelyeliminatethesetwotypesofedgedefects.

  • 标签: 缺陷分析 耐腐蚀钢 高强度 表面缺陷 生产过程 晶界扩散
  • 简介:IncombinationwiththeprocesstechnologyandequipmentatTangsteelColdRollingMill’s3~#galvanizedline,themechanismofdefect-formationofthestripsurfaceinthehotdipgalvanizedcoatinghasbeenanalyzed.Throughaseriesofreformabouttechnologyandequipmentgoodsolvedthedefectshasbeenfocusedoninthispaper.Thestripsurfacequalityinthehotdipgalvanizedcoatinghasbeenimprovedalot.

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  • 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:CO2emissionofthesteelindustrytakesupagreatproportionofthetotalemissionoftheworld.ItisnecessarytoreducetheCO2intensityofsteelproductsinordertosaveenergy,protecttheenvironmentandkeepasustainabledevelopmentinthesteelindustry.Basedontheresearchofsteelproducts'lifecycleinventory,thosewhoconductedthisresearchhavefocusedontheanalysisofCO2emissionfactorsandmeasures.Adoptingthelifecycleinventorymodelofacertainsteelmakingsite,togetherwiththeTornadoChart,theresearchershaveidentifiedsignificantfactors,providedsomeexplanation,andsuggestedsomepossiblemeasurestoreduceCO2emission.TheresultshaveshownthatthemostimportantfactorsaretheCO2intensityofblastfurnacegas(BFG),hotmetalratioofbasicoxygenfurnace(BOF)andthematerialutilizationefficiency.Accordingly,somemeasuressuchasremovingCO2inBFG,decreasingthehotmetalproportioninBOF,andimprovematerialutilizationefficiencyineachprocess,maybetakentodecreaseCO2emission.

  • 标签: CO2排放量 缓解方法 二氧化碳排放量 钢铁厂 生命周期清单 碱性氧气转炉