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简介:Thenumericalsimulationcanovercomethehardshipofmathematicalanalysisandexperimentalresearch,explicatethemechanismofmicrostructureshaping,predictmechanicalpropertiesandoperatinglifeofcastingsandthenoptimizetechnologyandcontrolmicrostructureformationtoobtainthequalifiedcastings.Thefinitedifferencemethod(FDM)isappliedtothesimulationoftemperaturefieldbasedonallkindsofnucleationandgrowthmodelsonallstagesofsolidificationofspheroidalgraphitecastiron.VisualC++isusedtoprogramthenumericalsimulationsoftware,QTstructure-1tosimulatethesolidificationprocessofspheroidalgraphitecastironandtheformationofallphasesinsolidificationprocess.Finally,theresultofsimulationiswellagreedwiththeexperimentalresult.
简介:以便区分充满的效果和暴烈的活动并且探索激发富有硅的铁矿石跟踪的活动(IOT)的方法,惰性的石英作为修正被引进标准,上好的影响,锻烧,热治好系统和一些另外的因素被红外调查,XRD,MIP,等等显微镜的方法。磨擦的试验性的结果表演和锻烧罐头仅仅改变SiO2,的非结晶的状态,IOT不在在房间温度下面治好的水泥举办暴烈的活动状况。热治好系统能刺激IOT的活动,特别压热器治好治好的臼系统能消费大量Ca(哦)2和难钙硅酸盐并且有更靠近的结构。当IOT粉末的特定的表面区域是800m2/kg,,30%水泥被IOT代替时,搽粉,有IOT的臼力量粉末比那甚至高与cementonly。
简介:Reducingthechloridecontentinregeneratedironoxides(RIO)fromsteel-picklingacidwasteeconomicallytreatedbyRuthnerprocessisthemostcriticalissueforthedevelopmentofRIOasausefulrawmaterialresource.Inthispaper,theresultsofanewmethodforcharacterizationandmodificationofRIOproducedinMobarakehSteelComplexwerereported.
简介:由使用焊接电线的镍,焊接弧的以铁酸盐为主要成的可锻的铁的部分熔化地区(PFZ)和焊接金属的机械性质的寒心的趋势上的alloying的效果系统地被学习了。在这个基础上,为以铁酸盐为主要成的可锻的铁(QT400-17)的弧焊的一个新镍电极第一次被开发。它的焊接金属的机械性质能以铁酸盐为主要成的可锻的铁匹配那些。在PFZ的碳化物层(WCL)的宽度显著地被减少,焊接关节有优秀马赫无能,焊接金属有高热的抗碎裂性。(编辑作者摘要)3个裁判员。
简介:Aporosity-freeandcontamination-freesurfacelayerwithgrainsizesrangingfromnanometertomicrometerinFesampleswasobtainedbysurfacemechanicalattritiontreatment(SMAT)technique.MechanicalandwearpropertiesofthesurfacelayerintheSMATedandannealedFesamplesweremeasuredbymeansofnanoindentationandnanoscratchtests,respectively.ExperimentalresultsshowedthatthehardnessofthesurfacelayerintheSMATedFesampleincreasedevidentlyduetothegrainrefinement.TheelasticnoduliofthesurfacelayersintheSMATedandannealedFesampleswereunchanged,independentofgrainsizeinthepresentgrainsizeregime.ComparedwiththeoriginalFesample,thewearresistanceenhancedandthecoefficientoffrictiondecreasedinthesurfacelayeroftheSMATedFesample.
简介:Dryseparationofironmineralfromlow-gradecoal-serieskaolininHubeiProvinceofChinawasinvestigated.ThestructureandchemicalcompositionofthekaolinoreweredeterminedbyX-raydiffraction(XRD)andX-rayFluorescence(XRF)analyses.Thenarrowparticlesizerangeclassification,drymagneticseparationandcalcinationwerecarriedouttoevaluatetheparticlesizedistribution,andtherelationbetweenthecontentofironandthewhiteness.Experimentalresultsrevealedthatthehighestcontentofiron(3.70%)inkaolinorewasintheparticlesizerangefrom60to74μm,andpyritewasthemainoccurrenceofironinthekaolinore.Drymagneticseparationshowedthattheremovalrateofironinkaolinorecouldbeincreasedobviouslyaftercalcination,andtherateofironremovalwas60%intheparticlesizerangefrom60to74μm.Aspyritecanbetransformedintohematitethroughcalcination,thermodynamicstudiesandXRDanalysisshowedthatthemaximumcontentofhematitewasobtainedat900℃,whichwouldbemorebeneficialtomagneticseparation.
简介:Theinternalstressinducedbyaporouslayerorpassivelayercanassisttheappliedstresstopromotedislocationemissionandcrackpropagation,e.g.whenthepipelinesteelisburiedinthesoilcontainingwater,resultinginstresscorrosioncracking(SCC).Moleculardynamics(MD)simulationisperformedtostudytheprocessofdislocationemissionandcrackpropagationinaslabofFecrystalwithandwithoutaporouslayeronthesurfaceofthecrack.Theresultsshowthatwhenthereisaporouslayeronthesurfaceofthecrack,thetensilestressinducedbytheporouslayercansuperimposeontheexternalappliedstressandthenassisttheappliedstresstoinitiatecracktipdislocationemissionunderloweredstressintensityKI,orstress.Torespondtothecorrosionaccelerateddislocationemissionandmotion,thecrackbeginstopropagateunderloweredstressintensityKI,resultinginSCC.
简介:Toobtainthecompatiblematerialofhighhardnessandhightoughness,Hadfieldsteelmatrixcomposites,reinforcedbyhigh-Crcastironbarsmadeofflux-coredweldingwires,whichwereinsertedintotheHadfieldsteelmelt,wereinvestigated.Themechanicalpropertiesofthreematerials,ie,compositesforas-castandquenching-watercondition,aswellasHadfieldsteel,werecompared.Theresultsshowthatthealloypowderinsideflux-coredweldingwirescanbemeltedbytheheatcapacityofHadfieldsteelmeltandsolidifyintohigh-Crcastironbars.Theimpacttoughnessofthecompositeforquenching-waterconditionishigherthanthatofthecompositeforas-castconditionandislowerthanthatoftheHadfieldsteel,butitcanstillmeettherequirementsofhardnessandtoughnessinindustrialapplication.Regardlessofloadvariation,compositeforquenching-waterconditionshowsbetterwearresistancethanthoseofthecompositeforas-castconditionandHadfieldsteel.ThemodifiedfracturetoughnessandwearresistanceofcompositesareattributedtonotonlythecombiningactionsofHadfieldsteelmatrixandhigh-Crcastironbars,butalsotheeffectofheattreatment.
简介:Theindustrialmanufactureprocessesofthreekindsofrollcoreusedductileironshavebeeninvestigatedviasystematicalexperiments.EffectsoftheratioofC/Si,pigiron,nodularizerandalloyingmethodonthemicrostructureandmechanicalpropertiesoftheheavysectionductileironhavebeenanalyzed.IthasbeenfoundthatwhentreatedwithRE-MgplusSb,highqualitynodularcastingscanbeproducedevenifmuchantispheroidizingalloyelementsareincludedinthepigiron.ThealloyelementSbplayedanimportantroleinthecontrolofgraphitemorphology.