ASNTNDTLevelIIIbasictrai教学讲解课件

MaterialsandProcessesJohnduPlessis2006WhyisitimportantforNDTpractitioners?

EvaluationofsuitabilityforserviceDefectdeterminationandelimination缺陷的判断和消除CauseofdefectAgenda日常事项，议程MaterialStructureStrengthandDeformation变形MaterialTestingPhasediagramsElementsinsteelAgendaSteelmakingHeatTreatmentMaterialTypesManufacturingProcessesStructureandbondingofmaterial结合MaterialstructureElementsAtomsElectronsProtons质子Neutrons核子PeriodicTable定期，周期AtomStructureCrystalstructure晶体BodyCenteredCubic体心立方体FaceCenteredCubic面心立方体ClosedpackedHexagonal密排六方体Crystallization结晶化，结晶体CrystalImperfections结晶缺陷Grainsize颗粒尺寸BodyCenteredCubicFaceCenteredCubicHexagonalclosedpackedCrystallization ThetransitionfromliquidtothesolidstateNucleiFormation核子形成Crystalgrowth晶体成长Crystallization

CrystallizationCrystallizationCrystallizationCrystallizationCrystalimperfectionsVacancy空缺，空虚Interstitialatom原子空隙Dislocations错位CrystalimperfectionsLatticeVacancyInterstitialAtomInterstitialAtomEdgeDislocationEdgeDislocationScrewDislocationScrewDislocationDislocationsinCopperGrainsizeGrainsizeisdeterminedbyRateofnucleation晶核成形RateofgrowthNucleationandgrowthGrainBoundaryGrainSizeMaterialBondsIonic离子Covalent共价的Metallic金属的VanderWaalsforces范德瓦力量CovalentBond共价结合TwoormoreatomsshareelectronsC+4H=CH4MetallicBondAtomsshareacloudofelectronswhichisfreetomovethroughoutthemetallicstructureIonicBond Oneelementgivesupelectronstoanotherformingtwochargedparticles,whichformsabond. Li+F=LiF

VanderWaalsForceStrengthandDeformationDeformationElastic松紧带橡皮带。弹性的，伸缩的Plastic橡胶，可塑性的Stress压力Strain张力拉力Young‘smodulus杨氏弹性Elasticdeformation Therecoveryoftheoriginaldimensionsofadeformedbodywhentheloadisremoved. Thelimitingloadbeyondwhichamaterialnolongerbehaveselasticallyistheelasticlimit.Elasticdeformation

PlasticDeformation Onexceedingoftheelasticlimitthebodywillexperienceapermanentsetofdeformationwhentheloadisremovedi.e.willnotreturntoitsoriginaldimensionsPlasticDeformation

DefinitionofStress Averagestress Load = --------------------------- crosssectionalareaDefinitionofStrain拉力 Averagelinearstrain = Ratioofchangeinthelength totheoriginallength

Hooke’sLaw StressisproportionaltostrainAverageStress-----------------=E(Young'sModulus)AveragestrainStressStrainCurvePropertiesofMetalsMechanicalPhysicalCorrosionOptical光学的，视觉的Nuclear核的，原子核MechanicalPropertiesModulusofElasticity

E=Stress/StrainDecreasewithIncreaseinTemperatureStructureInsensitive不敏感的，麻木不仁ModulusofElasticityMechanicalPropertiesTensileStrengthMaximumLoad/originalcrosssectionalareaStructureSensitiveChemicalcomposition,Structure,Grainsize,strainhistory,Temperatureetc.MechanicalPropertiesYieldStrength屈服强度 pointwhereincreaseinstrainoccurs withanincreaseinstressStructureSensitiveChemicalcomposition,Structure,Grainsize,strainhistory,TemperatureetcMechanicalPropertiesFatigueStrength疲劳强度

Maximumstressthatcanbesustainedforastatednumberofcycleswithout failureStressraiserslowersfatiguelimitMechanicalPropertiesDuctility延展性，温顺

Theamountofplasticdeformationbeforefracture破碎骨折断裂StructuresensitiveSizeandshapeoftestspecimen,temperature,strainrate,microstructureetc.MechanicalPropertiesFractureToughness刚性，韧性

AbilitytoresistfractureinthepresenceofanotchStructuresensitiveStrainrateNatureoftheloadTemperaturePhysicalPropertiesThermalConductivity热的MeltingTemperatureThermalExpansionandContraction膨胀和收缩ElectricalConductivityCorrosion Removalofmaterialordegradation降格退化ofthepropertiesofametalbychemicalorelectrochemicalprocesses,orbyacombinationofchemical,electrochemicalandmechanicalprocesses.CorrosionPropertiesWeldjointsbehavedifferentlyfromthebasemetalCorrosion

Corrosion

CorrosionSelectiveleaching选择性的浸出，析出Galvaniccorrosion直流电的，令人震惊的PittingcorrosionIntergranularcorrosion颗粒间的，晶粒间的StresscorrosioncrackingSelectiveLeachingPittingCorrosionIntergranular晶粒间stresscorrosioncrackingStresscorrosioncrackingofweldingElevated升起，举起TemperatureSteady固定的稳定的deterioration恶化变坏occurswhenexposedtohightemperatureforlongperiodsStrengthandHardnessdecreasewithincreasedtemperatureTlrolls轧辊,continuouscastorrollsMaterialtestsTensiletest拉伸试验Compressiontest抗压试验Fatiguetest疲劳试验Creeptest蠕变实验Impacttest冲击试验Bendtest弯曲试验Hardnesstest硬度试验TensiletestTensiletestTensiletestFatigueTest疲劳试验SNcurveStressvs.NumberofcyclesFatigue/endurance忍耐limitEffectofstressconcentrations集中FatigueTestCreep Plasticdeformationofamaterialwhichoccursasafunctionoftimewhenthematerialissubjectedtoconstant常数恒定不变的stressorload Normally正常的，和规则的associatedwith联合elevatedtemperatureCreep

ImpacttestingMeasureofductility延展性Temperaturedependant受抚养者Izod悬臂式Charpy沙尔皮ImpacttestingBendTestMeasureofductilityBendTestHardnesstestBrinell布氏Rockwell洛氏Vickers维氏Microhardness

显微硬度BrinellHardnesstestRockwellHardnesstestVickersHardnesstestVickersHardnesstestShoreScleroscope肖氏硬度计Theshorescleroscopemeasureshardnessintermsoftheelasticityofthematerial.Adiamond-tippedhammerinagraduatedglasstubeisallowedtofallfromaknownheightonthespecimentobetested,andthehardnessnumberdependsontheheighttowhichthehammerrebounds;theharderthematerial,thehighertherebound.ShoreScleroscopePhasediagramsandReactionsPhaseDiagramsPhasereactionsMonotectic偏晶的，偏晶体 Liquid1=Liquid2+SolidPeritectic包晶体的，包晶体 Liquid+Solid1=Solid2Peritectoid转熔体包晶的 Solid1+Solid2=NewSolid3PhasereactionsEutectic熔点最低的，共融的 Liquid=Solid1+Solid2Eutectoid共析体，共析的 Solid1=Solid2+Solid3PhasereactionPeritectic包晶体 Liquid+α=βPhasereactionPeritectoid包析体

β+α→γPhasereactionEutectic共融合金 Liquid=α+θPhasereactionEutectoid共析体 Solidα=β+γ

CoolingcurveforironFe–Fe3CPhaseDiagramPhasesofFe–Fe3CFerriteAusteniteDeltaFerriteCementite渗碳体Austenite Thisisthefacecenteredcubicstructureofsteel(GammaIron).Itisasolidstagestructurestable稳定的，牢靠的onlyathightemperatures(910°C-1400°C). Candissolve分解融化upto2%Carbonduetothelargerinterstitial空隙的，间隙的openingsbetweentheatomsAusteniteFerrite Thisisabodycenteredcubicstructureofsteel.(AlphaIron).

Itisasolidstagestructurestableatroomtemperature–canonlyaccommodate调节0.008%Carbonatroomtemperatureand0.025%Carbonat723°CduetothesmallinterstitialopeningsFerriteCementite Thisisacrystallinecompoundofironandcarbon(Fe3C)withanorthorhombic正交晶的crystalstructure.Itcontains6.67%Cbyweight.TransformationProductsPearlite珠光体Martensite马氏体Bainite贝氏体Pearlite CementiteandFerritejoininalamellar薄片状formtoproducePearlite. NormallyresultsfromthetransformationofAusteniteduringslowcooling.PearliteMartensite ThisstructureisobtainedwhenAusteniteisfastcooledandthus如此至此transformstobodycenteredtetragonal四角形的菱形的.MartensiteBainite Austenitedecomposes分解腐烂toformFerriteandCarbide.FormsinthetemperatureregionbetweenwhereMartensiteandPearliteformsBainiteFe–Fe3CPhaseDiagramEutectoidReaction共析转变Austenite↔Ferrite+IronCarbideEquilibriumconditions平衡条件0.83%C@723°CFerrite+IronCarbide=PearliteCalculate估算计算phaseswithleverrule@0.83%CPhaseQuantitiesά 0.025%__________________6.67%Fe3C

Λ0.83%ά=6.67–0.83X100

6.67–0.025=88.4%Fe3C=100–88.4=11.6%TimeTemperatureTransformation-DiagramTTT–DiagramContinuousCoolingDiagramAlloying AnAlloyisasubstance物质thathasmetallicpropertiesandiscomposedoftwoormorechemicalelements. Austenitestabilizers奥氏体稳定剂

FerritestabilizersPurposeofAlloyingIncreasehardenabilityImprovestrengthImprovemechanicalpropertiesateitherhighorlowtemperaturesImprovetoughness韧性Improvewearresistance耐磨性ImprovecorrosionresistanceImprovemagneticproperties.ChemicalelementsinSteelCarbonManganese锰SiliconSulpherPhosphorous磷Nickel镍ChromiumMolybdenumV,Ti,AlChemicalElementsinSteelCarbon(C)Upto2%IncreasehardnessandstrengthReducesweldabilityManganese(Mn)Upto1.5%IncreasehardenabilityBondswithSChemicalElementsinSteelSilicon(Si)Upto1%Deoxidizer去氧剂，还原剂IncreasestrengthSulphur(S)Undesirable–aslowaspossibleReduceweldabilityChemicalElementsinSteelPhosphorous(P)StrengthenslowcarbonsteelImprovesmachinabilityChromium(Cr)IncreaseoxidationresistanceIncreasehardenabilityResistsabrasionandwear腐蚀和耐磨ChemicalElementsinSteelMolybdenum(Mo)Upto1%Carbideformer碳化物形成者IncreasehardenabilityandstrengthatelevatedtemperatureNickel(Ni)IncreasetoughnessandhardenabilityCorrosionResistanceChemicalElementsinSteelAluminium(Al)Deoxidizerandgrainrefiner去氧剂和晶粒细化剂Alloyinnitridingsteels合金在氮化物Vanadium(V)GrainrefinerResiststemperingIncreasehardenabilityChemicalelementseffectonphasediagramNiandMnlowerscriticaltemperature降低临界温度Mo,Al,Si,WandVraiseslowercriticaltemperature提高临界温度ModernSteelmakingSteelmakingOpenHearth平炉Bessemer酸性转炉钢Electricarc电弧BlastFurnace高炉鼓风炉SteelmakingHeatTreatmentHeatTreatment Acombinationofheatingandcoolingoperations,timedandappliedtoametaloralloyinthesolidstateinawaythatwillproducedesiredproperties.HeatTreatmentAnnealing退火锻练Normalizing常态化，标准化，正火StressRelieving应力消除HardeningandTempering硬化及退火Annealing Heatingofsteeltotemperature(Austeniteregion)andslowcooling(furnace)throughthetransformationrangeStressrelievingGrainrefiningSofteningAnnealing

Annealing

Normalizing正火 Heatingofsteeltotemperatureabovetheuppercriticalline(A3orAcm)andcoolinginstillairtoroomtemperature.GrainrefinementAlleviatechemicalsegregation缓和化学间隙SteelisharderandstrongerthanwhenannealedNormalizing

Stressrelieving550–650°CNomajorchangesinmicrostructureHardeningHeattoAusteniteregionFastcooling–QuenchinoilorwaterAustenitetransformstoMartensiteTempering HeatingofthehardenedsteeltosometemperaturebelowthelowercriticaltemperatureRelievesstressImprovesductilityandtoughnessReduceshardnessandstrengthTempering

EffectoftemperingonpropertiesReducesUTS极限抗拉强度ReducesYieldstrengthImproveselongation伸长ImprovesreductionofareaImprovesductility韧性HardeningSurfaceHeatTreatmentsCarburizing渗碳Nitriding氮化Carbonitriding(Cyaniding)碳化FlameHardening火焰表面硬化InductionHardening感应淬火Carburizing/CaseHardeningLowcarbonsteel(%C<0.2)HardwearresistantouterlayerSolidmedia,saltbathorgasAtmosphereisCOrichCarburizing/CaseHardeningTemperature=925°CDiffusionreaction散射Austenite(Fe)+2CO→CarbonenrichedAustenite+CO2MartensitetransformationoncoolingCarburizing/CaseHardeningNitridingFerriticthermochemicaltreatmentAl,Cr,Mo500-590°CDiffusionreactionNotransformationoncoolingNitridingNitridingHighsurfacehardnessHighwearstrengthHightemperresistanceHightemperaturehardnessisgoodHighfatiguestrengthInductionhardeningElectriccoil–magneticfield–eddycurrents–heatmaterialLocalizedheatingandcooling%C>0.25InductionhardeningInductionhardeningFlameHardening Heatworkpiecewithflameanddirectquenchingoraircooling0.3>%C<0.6StressrelieveafterquenchingFlameHardening

CommonMaterialsSteelTypesLowCarbonSteel(0–0.25%C)MediumCarbonSteel(0.25–0.6%C)HighCarbonSteel(0.60–2.0%C)SteelTypesLowAlloySteelCastIron(2.0–6.67%C)StainlesssteelsLowCarbonsteelRelativelysoftEasilydeformedandshapedNails,Structuralshapes,pipe,wireLowCarbonsteelMicrostructureMediumCarbonsteelCanbehardenedbyquenchingCanbetemperedHigherstrengththanlowcarbonsteelsShafts,Axles,machinepartsHighCarbonsteelCanbehardenedbyquenchingCanbetemperedHammers,Chisels,Drills,SpringsLowAlloysteelMn,Ni,Cr,Mo,Cu,VQuenchedandTemperedIncreasedStrength,Ductility,FatigueresistanceandWearresistanceShafts,Gears,Torsionbars,Pins,Construction,TransportationGalvanizedSteel镀锌钢ZnrichcoatingCorrosionprotectionHotDipGalvanizingCastirons2-6.67%CarbonWhitecastironMalleablecastironGreycastironNodularcastironWhiteCastIronAllcarboniscombined-Cementite2.5–4.3%C(Hypoeutectic)Si<1.3%WhiteCastIronWhiteCastIronHardandwearresistantBrittleDifficulttomachineLinersformixersandmillsMalleableCastIron Carbonisuncombined–irregularroundparticlesHeattreatedwhitecastiron2–2.65%C0.9–1.4%SiMalleableCastIronAxlesanddifferentialhousingsCrankshaftsGreyCastIron Carbonisuncombinedintheformofgraphiteflakes2.5–4.0%C1.5–5.0%SiGreyCastIronGreyCastIronHardnessisdeterminedbymicrostructureGearhousings,pumphousingFirehydrants,sewercoversNodularCastIronDuctileorSGironCarbon/Graphite-spheroidsDuctileMotorframes,cylinderheads,crankshafts,pistons,millrollsNodularCastIronStainlesssteelsFerriticMartensiticAusteniticDuplexPrecipitationhardeningFerriticStainlesssteel14–27%Cr–LowCMagneticCannotbehardenedbyheattreatment441,430,409ColdformeasilyFerriticStainlesssteelBrittlePoorweldabilityGraingrowthGrainboundaryembrittlementNitricacidtanks,furnaceparts,annealingbaskets,decorativeAusteniticStainlesssteel18/8types18–25%Cr,8-14%Ni,0-3%MoNonMagneticCannotbehardenedbyheattreatmentAusteniticStainlesssteelAusteniticStainlesssteelColdworked–workhardens304,308,316,310Shockresistant,GoodweldabilityPulphandling,boilershells,foodandchemicalhandling,heattreatmentequipmentMartensiticStainlesssteel0.15–1.2%C,1.5–18%Cr410,420,431MagneticCanbehardenablebyheattreatmentMartensiticStainlesssteelPoorweldabilityControlledpre/postheatingTurbine,pumpshafts,cutlery,surgicalinstruments,valvesDuplexstainlesssteel0.03–0.06%C,19–28%Cr,1–8%Ni,0.5–4%Mo,0.1–0.35%N,0.05–2.5%Cu2205,2507FerriteandaustenitemicrostructureDuplexstainlesssteelDuplexstainlesssteelImprovedintergranular,andpittingcorrosionresistanceImprovedstresscorrosioncrackingresistanceChemicalprocessing,OilandGasindustryPrecipitationhardeningstainlesssteel17-4PH,17-7PH15-17%Cr,4–10%Ni,Cu,AlTemperedMartensitewithagehardenedprecipitatesPumps,rocketcasingsNopreheatbutpostweldheattreatmenttorestorepropertiesAluminiumPureAlAl-Cu 2xxxAl-Mn 3xxxAl-Si 4xxxAl-Mg 5xxxAl-Mg-Si 6xxxAl-Zn 7xxxCopperPurecopperBrass(Cu+Zn)Bronze(Cu+Sn;Si;Al;Be)CupronickelPlasticsMonomer–polymerization–plasticThemoplasticThermosetManufacturingProcessesCastingWeldingRollingExtrusionPressingDrawingCastingObtainGeometryPatternmakingCoremakingMoldingMeltingandpouringCleaningCastingVacuumDieCastingCastingCastingDefectsMetallicprojections - JointFlashorFinsCavities - BlowholesandpinholesDiscontinuities - HotcrackingSurfaceDefects - FlowmarksIncompletecastings- PouredshortIncorrectdimensionandshapeMetallicinclusionsCastingDefectsPipemakingPowderMetallurgyPowderMetallurgyExtrusionExtrusionExtrusionHotRollingRollingProfilesForgingClosedDieForgingOpenDieForgingForgingDefectsStartingMaterialSeamsandlapsInternalCracksForgingProcessSurfacecracksDecarburizationPorosityForgingDefectsDrawingDeepDrawingStampingPressingWeldingProcessesWeldingProcessesArcweldingElectricresistanceheatingElectronbeamPlasmaarcFrictionweldingWeldingProcessesUltrasonicweldingElectroslagExplosionweldingDiffusionweldingArcweldingprocessesShieldedMetalArcWelding(SMAW)GasMetalArcWelding(GMAW)FluxCoredArcWelding(FCAW)SubmergedArcWelding(SAW)GasTungstenArcWelding(GTAW)ShieldedMetalArcWeldingShieldedMetalArcWeldingFerrousandNonferrousBasemetalsLowCarbonCoreWireCarbonates,Rutile,Fluorides,Metalalloys,CelluloseandSilicateBindersShieldedMetalArcWeldingFluxCoatingFunctionsArcstabilizationGasshield–removeairSlag–protect,supportandinsulateAlloyingDeoxidersandfluxingagentsElectricalcharacteristicsShieldedMetalArcWeldingSelectinganelectrodeWeldingPositionWeldingcurrentJointdesignandfit-upServiceconditionsProductionefficiencyShieldedMetalArcWeldingProcessvariablesAmperageVoltageOCVArclengthSkilllevelShieldedMetalArcWeldingAdvantagesVersatileManyelectrodetypesAllpositionsRangeofthicknessesLowstart-upcostEasytouseShieldedMetalArcWeldingDisadvantagesLowdepositionrate(1–8kg/hour)HighlabourandconsumablecostElectrodeclassificationAWSElectrodeclassificationER70XX-YGasMetalArcWeldingGasMetalArcWeldingFerrousandNonferrousbasemetalCarbon,alloysteelandnonferrouswireGasshieldCO2,Argon,Mixedgas(Ar,O2,H2,He,CO2)Spray,Globular,ShortCircuitTransfermodesGasMetalArcWeldingProcessVariablesAmperageVolta