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106 个结果
  • 简介:ItisfundamentallyimportanttounderstandtheinfluenceofstrainonthedensityofdeformationtwinsinTWIPsteelbecausetwinningisitsdominantdeformationmechanism.ThedeformationbehaviorofaFe-30Mn-4Si-3Al-0.097CsteelhasbeeninvestigatedbyX-raydiffraction(XRD),electronbackscatterdiffraction(EBSD)andtransmissionelectronmicroscopy(TEM)techniques.Samplewithanaveragegrainsizeof10μmwasdeformedincold-rollingwithareductionof10%,20%,30%,40%,50%,60%and70%,respectively.Themechanicalpropertiesofthecold-rolledsampleswerefurtherinvestigatedbytensiletests.Theyieldstrength(σy)andultimate-tensile-strength(σUTS)oftheas-preparedsampleis480MPaand850MPa,respectively.However,undercoldrollingdeformation,thetensilestrengthobviouslyincreaseswithanincreaseinrollingreduction.Thesamplewitharollingreductionof10%exhibitsσyof610MPaandσUTSof-1000MPa.Theyieldstrengthandtensilestrengtharefurtherenhancedupto1320MPaand1378MPaforthespecimenwitharollingreductionof70%,regardlessofthepoorductilityof6.7%.ThedeformationmicrostructureswerestudiedbyEBSDandTEMobservations.Itisfoundthat,withincreasingrollingreduction,theaveragedistancebetweendeformationtwinsdecreasesgraduallywhilethedensityofdeformationtwins(thelengthoftwinboundaryinunitarea)exhibitamaximumvalueat40%cold-rolling+tension.Carefullystatisticsanalysisrevealsgrainorientationiscloselyrelatedtothedeformationtwinsandtheunderlyingmechanismgoverningthetwinningisdiscussed.

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  • 简介:ThemicrostructuralchangesofFe83Si4B13amorphousmotheralloyduringtheheatingprocesswereinvestigatedbyLaserScanningConfocalMicroscopy(LSCM),andthephasetransformationwasdeterminedbytheThermo-Calccalculations.ThedifferencesinthemeltingpointsmeasuredbyDifferentialScanningCalorimetry(DSC)andLSCM,andthoseobtainedbyThermo-Calccalculationswerealsodiscussed.ItisfoundthatthemeltingpointsmeasuredbyDSCandLSCMarerelativelysimilar,whereastheonsetandendofthemeltingtemperaturescalculatedbyThermo-CalcsoftwarearehigherthanthosemeasuredbyDSCandobservedbyLSCM.

  • 标签: 加热过程 计算值 母合金 激光扫描共聚焦显微镜 差示扫描量热法 LSCM
  • 简介:铁矿石经浓盐酸和少量的SnCl2溶液加热到45℃溶解后,用SnCl2-TiCl3还原滴定Fe(Ⅲ),使Fe(Ⅲ)还原为Fe(Ⅱ),再以K2Cr2O7滴定全铁含量。本方法对实验操作温度,试样溶解酸的选择有一定的要求,宜选用非氧化性强酸在30-60℃溶解矿样。

  • 标签: 铁矿石 SnCl2-TiCl3-K2Cr2O7滴定法 Fe(Ⅱ) Fe(Ⅲ)
  • 简介:High-strengthsteelshavebeenwidelyappliedtoautomotivechassisparts.Inordertoformcomplexshapes,highholeexpansionratesandhighformabilityarerequired.Dualphase(DP)steelhasagoodformability,butapoorholeexpansionrate.Inthiscircumstance,anotherkindofsteelwhichhasamicrostructureofferrite-bainite,ratherthanferrite-martensite,hasbeenfoundtobeanalternativesolution.ItiscalledFBsteel.ThissteelwithSi,CandMnadditionsareappliedinthisstudy.Atwo-stepcooling...

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  • 简介:Thisstudyaimstoinvestigatetheeffectofthe1-stepquenchingandpartitioning(Q&P)processonthemicrostructureandtheresultingVicker’shardnessof0.3C-1.5Si-1.5Mnsteelbyusingin-situdilatometry,opticalmicroscopy(OM),scanningelectronmicroscopy(SEM),X-raydiffractometry(XRD),andVicker’shardnessmeasurement.Systematicanalysesindicatethatthemicrostructureofthespecimensquenchedandpartitionedat150℃,200℃,250℃,and300℃mainlycompriseslathmartensiteandretainedaustenite.Thedilatometrycurveofthespecimenpartitionedat150℃ispresumablyascribedtotheformationofisothermalmartensite.Intheearlystagesofpartitioningat200℃,thenearlyunchangeddilatationcurveiscloselyrelatedtothesynergisticeffectofisothermalmartensiteformationandtransitionalepsiloncarbideprecipitation.Inthelaterstagesofpartitioningat200℃,theslightincreaseinthedilatationcurveisduetothecontinuousisothermalmartensiteformation.Withfurtherincreaseinpartitioningtemperatureto250℃,thedilatationincreasesgraduallyupto3600s,whichisrelatedtocarbonpartitioningandlowerbainiteformation.Partitioningatahighertemperatureof300℃causesarapidincreaseinthedilatationcurveduringtheinitialstages,whichsubsequentlylevelsoffuponprolongingthepartitioningtime.Thisismainlyattributedtotherapiddiffusionofcarbonfromathermalmartensitetoretainedausteniteandcontinuousformationoflowerbainite.

  • 标签: 淬火温度 钢组织 分区 板条马氏体 扫描电子显微镜 膨胀曲线
  • 简介:Cr2O3-formingferriticstainlesssteelshavebeenwidelyexploredasintermediatetemperaturesolidoxidefuelcells(SOFCs)interconnects.However,theevaporationofchromiascalemightmigratetoandpoisonthecathode,leadingtodegradationofthecellperformance.Inthisstudy,Ni-Co-Fe-Pcoatingsweredepositedontheferriticstainlesssteelbymeansofacost-effectivetechniqueofelectrolessmethod.Theyareexpectedtobeconvertedinto(Ni,Co,Fe)3O4spinelwithahighelectricalconductivityandCTEmatchwithstainlesssteel,whichcanblocktheevaporationofchromiaformedonsteelsubstrateexposedtothecathodeenvironmentoftheSOFC.TheeffectsofpH,massratioofFeSO4/(FeSO4+NiSO4+CoSO4)andtemperatureofsolutiononthedepositionrate,compositions,surfacemorphologiesandstructuresoftheNi-Co-Fe-Pcoatingswereinvestigated.TheresultsindicatedthatthedepositionrateincreasedwithincreasingpHwhenpHwaslowerthan9andthenreducedwhenpHwashigherthan9.Thedepositionrateincreasedwithincreasingtemperaturewhentemperaturewaslowerthan80℃andthendecreasedwhentemperaturewashigherthan80℃.ThedepositionratedecreasedwiththeincreaseinmassratioofFeSO4/(NiSO4+CoSO4+FeSO4).ThecoatingsconsistedofNi,Co,FeandP.Thephasestructureofthecoatingwasamorphous.

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  • 简介:采用退火工艺来消除钢锭内应力、减少化学成分偏析及显微组织的不均匀性,适当调整制造工艺,在不增加成本的前提下,锻造出合格的锻件,并最终加工成符合技术要求的产品。

  • 标签: 60SI2MN 裂纹 退火
  • 简介:针对60Si2Mn弹簧圆钢在拉伸试验中发生脆断的失效样品进行断口、夹杂物、金相组织等分析检验,发现脆断的主要原因与热处理过程中的淬火温度、回火时间及操作程序均有较密切的关系。

  • 标签: 60SI2MN 脆性断裂 断口组织
  • 简介:ThehotductilityofFe-36NiinvaralloywithdifferentadditionsoftheelementceriumwasinvestigatedusingaGleeble-3800thermal-mechanicalsimulatoroverthetemperaturerange850-1050℃,andtheimprovementmechanismofthehotductilitywasanalyzedusingacombinationofSEM,EDS,andOM.TheresultsindicatedthatFe-36Niinvaralloyexhibitedpoorhotductilitybelow1050℃,whichwasmainlyattributedtoweakgrainboundariesandtheactionofgrainboundarysliding.However,thealloyswithceriumcontentsof0.016%and0.024%bothdemonstratedsubstantialimprovementinthehotductilityovertheentiretestingtemperaturerange.Theobservedimprovementofthehotductilityofthealloywith0.016%ceriumat950℃andthealloywith0.024%ceriumat900℃wasassociatedmainlywiththegrainboundarystrengtheningandtherestrictionofthegrainboundaryslidingbecausetheadditionofceriumreducedthesegregationofsulfuratgrainboundariesandrefinedthegrainstructure.Theoccurrenceandaccelerationofdynamicrecrystallizationwerefoundtoberesponsibleforthehighhotductilityofthealloywith0.016%ceriumat1000℃andthealloywith0.024%ceriumat950-1000℃asaresultoftherefinementofthegrainstructurebyadditionofcerium.

  • 标签: 因瓦合金 高温塑性 晶界滑移 温度范围 晶粒结构
  • 简介:TheeffectofCe,LaandmischmetalonthesolidificationstructureofFe-36Niinvaralloywasinvestigated.Theresultsshowthatgreatamountsofhigh-meltingpointcompounds(Ce2O3,La2O2Sand(Ce,La)2O2S)respectivelyformedinthealloywiththeadditionofCe,Laormischmetal.Basedonthetheoryoflatticemisfit,thelatticemisfitbetweenthe(0001)surfacesofCe2O3,Ce2O2SandLa2O2Sand(100)surfaceofFe-36Niinvaralloywere6.21%,5.77%and5.42%,respectively,whicharerelativelylow.Therefore,Ce2O3,La2O2Sand(Ce,La)2O2Scouldserveasthecoreofheterogeneousnucleation,improvetheequiaxedgrainratio,reducetheequiaxedgrainsizeandrefinethesolidificationstructureofalloy.

  • 标签: 因瓦合金 混合稀土 凝固组织 非均质形核核心 催化能力 晶格失配
  • 简介:介绍高速铁路用弹簧钢38Si7线材生产技术要求和工艺开发过程,从孔型系统、料型制度、生产管理等方面进行了优化,逐渐扩大南钢高速铁路用弹簧钢38Si7线材市场占有力。

  • 标签: 弹簧钢 38Si7 开发
  • 简介:通过对国家标准中60Si2Mn弹簧圆钢试样热处理工艺的试验和改进,提出了适合鄂钢产60Si2Mn弹簧圆钢试样的热处理工艺,满足了国家标准对60Si2Mn弹簧圆钢各项力学性能指标的要求。

  • 标签: 60SI2MN 弹簧圆钢 试样 热处理 性能
  • 简介:Theeffectsofthefinalelectromagneticstirring(EMS)onthesolidificationstructureof60Si2CrVAThighstrengthspring(HSS)steelofcontinuouscasting(CC)billetshasbeenstudied.Theanalysisofthesolidificationstructureisbasedonthecomparisonbetweenthemacrostructure,microstructure,carbonsegregationanddefectsofthe60Si2CrVATbilletwithmold-electromagneticstirring(M-EMS)andthosewiththeM+finalsolidificationzoneelectromagneticstirring(F-EMS).ItisfoundthatthesolidificationstructureofthebilletwiththeF-EMSisimprovedwiththetightnessofthebilletandtheincreaseintheratiooftheequiaxedstructure,theinnerporosityandtheshrinkageareremarkablyreduced,andthattheratioofcentralcarbonsegregationsharplydecreases.Meanwhile,thesecondarydendritearmspacing(SDAS)isimproved,andtheratioofcentralequiaxedgrainconsiderablyincreases,whichresultsinfinergrains.Therefore,thequalityofthebilletisenhancedwiththeF-EMS.

  • 标签: 环境管理体系 凝固组织 钢坯质量 弹簧钢 电磁搅拌 凝固结构
  • 简介:Thehot-deformationbehaviorofFe-Mn-Ctwinninginducedplasticity(TWIP)steelwasinvestigatedbyconductinghotcompressiontestswithinarecommendedhotrollingtemperaturerangeatvariousstrainrates.Flowresistancecurvesduringhot-deformationwereobtained,andstrainratesensitivitiesandactivationenergiesforplasticdeformationwerecalculatedusingthepowerlaw.ItisfoundthattheadditionofAlandSiclearlyincreasesthepeakstressesforthepresentalloys,especiallyat950℃.ButMnhasaminoreffectonthestress-straincurvesandactivationenergywhenitscontentvariesfrom15mass%to22mass%forthepresentalloys.

  • 标签: 炼钢过程 温度范围 热轧 冶炼技术
  • 简介:检测技术是一种检测效率较高、准确性高的无损检测技术。本文介绍了漏探伤的基本原理、组成和检测时的影响因素。并结合该技术在南钢弹簧棒材产品检测中的应用,针对影响现场漏检测结果的因素进行分析和研究,以期得到更准确的检测结果,使漏检测技术更好的服务于棒材的检测。

  • 标签: 漏磁检测 无损检测 缺陷 弹簧钢棒
  • 简介:文章简单介绍了60Si2MnT铁路Ⅲ型弹条用钢现状,叙述了鄂钢生产Ⅲ型弹条用钢的工艺研究及过程控制情况以及试生产结果。

  • 标签: Ⅲ型弹条 疲劳寿命 真空处理
  • 简介:Opticalmicroscope(OM),scanningelectronmicroscope(SEM),energydispersivespectrometer(EDS)andX-rayDiffraction(XRD)wereusedtostudytheeffectsofrareearthonthemicrostructuralcharacteristicsof55%Al-Zn-1.6%Sihot-dipcoatingsonsteel.TheresultsofOM,SEMandEDSshowedthatbyaddingREintothe55%Al-Zn-1.6%Sibath,thesaw-toothedshapeofintermetallicreactionlayerofcoatingbecamesmooth,andthethicknessoftheoverlayandintermetallicreactionlayerdecreased.TheXRDresultsrevealedthattheintermetallicreactionlayerwascomprisedoftwodifferentregions,abrightphaseclosesttothesteelsubstratewithphasesofFe2Al3andadarkphaseclosesttothemetalliccoatingwithphasesofFeAl3/α-Fe-Al-Si.

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  • 简介:Resultspresentedinthisstudycontributetoinvestigationofthemicrostructureandmechanicalpropertiesofthehot-rolledFe16Mn0.6Csteelplates.Thesteelplateshavebeenproducedbybeinghot-rolledattemperaturesrangingfrom1100℃to850℃insevenpassesto97.5%reductioninthicknessandthencooledinafurnaceof650℃.Someplateshavebeenannealedattemperaturesrangingfrom300℃to1100℃for5minto60min,andthenfollowedbywaterquenching.Thereareannealingtwinsinthehot-rolledFe16M...

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  • 简介:TheFe-Ti-Nmateralloywaspreparedthroughthein-situreactionofnitrogengaswiththeFe-Timelt.ScanningelectronmicroscoperesultsshowthattheparticlesuniformlydistributedintheironmatrixwereTiN.ThedeliberatelypreparedFe-Ti-Nmasteralloywasemployedforthe409Lferriticstainlesssteelinanattempttorefinetheas-castsolidificationstructure.ItwasfoundthattheeffectivenessofFe-Ti-Nmasteralloyonrefiningoftheas-cast409Lferriticstainlesssteelwasaffectedbyadditionlevel,holdingtimeandmeltstemperature.Itwasfoundthattheaverageequiaxedgrainsizedecreasedfrom1503μmto303μm,theproportionofequiaxedgrainzoneincreasedfrom14%to100%withincreasingtheFe-Ti-Nmasteralloyadditionlevelto2.5%.Theproportionofequiaxedgraindecreasedfrom85%to4%asthesolidificationtemperatureincreasedfrom1803Kto1883K.Whentheholdingtimereachedto8min,thesolidificationstructuresof409Lferriticstainlesssteelshowextremepointsintheproportionofequiaxedgrain.Itisclearthatthegrainrefiningefficiencygraduallyfadeawaywiththeincreasingoftheholdingtimeattheverybeginning.However,whentheholdingtimecontinuestoincreaseandexceedstheextremepoint,thegrainrefiningefficiencyoftheFe-Ti-Nmasteralloyrecoveredtoacertaindegree.Theexperimentalresultsmentionedabovehavebeenanalyzedintermsofthermodynamics.Underappropriateconditions,theFe-Ti-Nmasteralloyusedforgrainrefinementofthesolidificationstructureof409Lferriticstainlesssteelmayhavegoodprospectsforindustrialapplications.

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