ASNTNDTLevelIIIbasictrai教學(xué)講解課件

MaterialsandProcessesJohnduPlessis2006MaterialsandProcessesJohnduASNTNDTLevelIIIbasictrai教學(xué)講解課件WhyisitimportantforNDTpractitioners?

EvaluationofsuitabilityforserviceDefectdeterminationandelimination缺陷的判斷和消除CauseofdefectWhyisitimportantforNDTprAgenda日常事項(xiàng)，議程MaterialStructureStrengthandDeformation變形MaterialTestingPhasediagramsElementsinsteelAgenda日常事項(xiàng)，議程MaterialStructurAgendaSteelmakingHeatTreatmentMaterialTypesManufacturingProcessesAgendaSteelmakingStructureandbondingofmaterial結(jié)合StructureandbondingofmaterMaterialstructureElementsAtomsElectronsProtons質(zhì)子Neutrons核子PeriodicTable定期，周期MaterialstructureElementsAtomStructureAtomStructureASNTNDTLevelIIIbasictrai教學(xué)講解課件Crystalstructure晶體BodyCenteredCubic體心立方體FaceCenteredCubic面心立方體ClosedpackedHexagonal密排六方體Crystallization結(jié)晶化，結(jié)晶體CrystalImperfections結(jié)晶缺陷Grainsize顆粒尺寸Crystalstructure晶體BodyCenterBodyCenteredCubicBodyCenteredCubicFaceCenteredCubicFaceCenteredCubicHexagonalclosedpackedHexagonalclosedpackedCrystallization ThetransitionfromliquidtothesolidstateNucleiFormation核子形成Crystalgrowth晶體成長Crystallization ThetransitionCrystallization

Crystallization CrystallizationCrystallizationCrystallizationCrystallizationCrystallizationCrystallizationCrystallizationCrystallizationCrystalimperfectionsVacancy空缺，空虛Interstitialatom原子空隙Dislocations錯位CrystalimperfectionsVacancy空缺CrystalimperfectionsCrystalimperfectionsLatticeVacancyLatticeVacancyInterstitialAtomInterstitialAtomInterstitialAtomInterstitialAtomEdgeDislocationEdgeDislocationEdgeDislocationEdgeDislocationScrewDislocationScrewDislocationScrewDislocationScrewDislocationDislocationsinCopperDislocationsinCopperGrainsizeGrainsizeisdeterminedbyRateofnucleation晶核成形RateofgrowthGrainsizeGrainsizeisdetermNucleationandgrowthNucleationandgrowthGrainBoundaryGrainBoundaryGrainSizeGrainSizeMaterialBondsIonic離子Covalent共價的Metallic金屬的VanderWaalsforces范德瓦力量MaterialBondsIonic離子CovalentBond共價結(jié)合TwoormoreatomsshareelectronsC+4H=CH4CovalentBond共價結(jié)合TwoormoreMetallicBondAtomsshareacloudofelectronswhichisfreetomovethroughoutthemetallicstructureMetallicBondAtomsshareacloIonicBond Oneelementgivesupelectronstoanotherformingtwochargedparticles,whichformsabond. Li+F=LiFIonicBond Oneelementgivesu

VanderWaalsForceVanderWaalsForceASNTNDTLevelIIIbasictrai教學(xué)講解課件StrengthandDeformationStrengthandDeformationDeformationElastic松緊帶橡皮帶。彈性的，伸縮的Plastic橡膠，可塑性的Stress壓力Strain張力拉力Young‘smodulus楊氏彈性DeformationElastic松緊帶橡皮帶。彈性的Elasticdeformation Therecoveryoftheoriginaldimensionsofadeformedbodywhentheloadisremoved. Thelimitingloadbeyondwhichamaterialnolongerbehaveselasticallyistheelasticlimit.Elasticdeformation TherecoveElasticdeformation

Elasticdeformation PlasticDeformation Onexceedingoftheelasticlimitthebodywillexperienceapermanentsetofdeformationwhentheloadisremovedi.e.willnotreturntoitsoriginaldimensionsPlasticDeformation OnexceediPlasticDeformation

PlasticDeformation DefinitionofStress Averagestress Load = --------------------------- crosssectionalareaDefinitionofStress AverageDefinitionofStrain拉力 Averagelinearstrain = Ratioofchangeinthelength totheoriginallength

DefinitionofStrain拉力 AveraHooke’sLaw StressisproportionaltostrainAverageStress-----------------=E(Young'sModulus)AveragestrainHooke’sLaw StressisproportStressStrainCurveStressStrainCurvePropertiesofMetalsMechanicalPhysicalCorrosionOptical光學(xué)的，視覺的Nuclear核的，原子核PropertiesofMetalsMechanicalMechanicalPropertiesModulusofElasticity

E=Stress/StrainDecreasewithIncreaseinTemperatureStructureInsensitive不敏感的，麻木不仁MechanicalPropertiesModulusoModulusofElasticityModulusofElasticityMechanicalPropertiesTensileStrengthMaximumLoad/originalcrosssectionalareaStructureSensitiveChemicalcomposition,Structure,Grainsize,strainhistory,Temperatureetc.MechanicalPropertiesTensileSMechanicalPropertiesYieldStrength屈服強(qiáng)度 pointwhereincreaseinstrainoccurs withanincreaseinstressStructureSensitiveChemicalcomposition,Structure,Grainsize,strainhistory,TemperatureetcMechanicalPropertiesYieldStrMechanicalPropertiesFatigueStrength疲勞強(qiáng)度

Maximumstressthatcanbesustainedforastatednumberofcycleswithout failureStressraiserslowersfatiguelimitMechanicalPropertiesFatigueSMechanicalPropertiesDuctility延展性，溫順

Theamountofplasticdeformationbeforefracture破碎骨折斷裂StructuresensitiveSizeandshapeoftestspecimen,temperature,strainrate,microstructureetc.MechanicalPropertiesDuctilityMechanicalPropertiesFractureToughness剛性，韌性

AbilitytoresistfractureinthepresenceofanotchStructuresensitiveStrainrateNatureoftheloadTemperatureMechanicalPropertiesFracturePhysicalPropertiesThermalConductivity熱的MeltingTemperatureThermalExpansionandContraction膨脹和收縮ElectricalConductivityPhysicalPropertiesThermalConCorrosion Removalofmaterialordegradation降格退化ofthepropertiesofametalbychemicalorelectrochemicalprocesses,orbyacombinationofchemical,electrochemicalandmechanicalprocesses.Corrosion RemovalofmaterialCorrosionPropertiesWeldjointsbehavedifferentlyfromthebasemetalCorrosionPropertiesWeldjointCorrosion

Corrosion Corrosion

Corrosion CorrosionSelectiveleaching選擇性的浸出，析出Galvaniccorrosion直流電的，令人震驚的PittingcorrosionIntergranularcorrosion顆粒間的，晶粒間的StresscorrosioncrackingCorrosionSelectiveleaching選擇性SelectiveLeachingSelectiveLeachingASNTNDTLevelIIIbasictrai教學(xué)講解課件ASNTNDTLevelIIIbasictrai教學(xué)講解課件PittingCorrosionPittingCorrosionASNTNDTLevelIIIbasictrai教學(xué)講解課件Intergranular晶粒間stresscorrosioncrackingIntergranular晶粒間stresscorrosStresscorrosioncrackingofweldingStresscorrosioncrackingofwElevated升起，舉起TemperatureSteady固定的穩(wěn)定的deterioration惡化變壞occurswhenexposedtohightemperatureforlongperiodsStrengthandHardnessdecreasewithincreasedtemperatureThermalcyclingi.e.millrolls軋輥,continuouscastorrollsElevated升起，舉起TemperatureSteadMaterialtestsTensiletest拉伸試驗(yàn)Compressiontest抗壓試驗(yàn)Fatiguetest疲勞試驗(yàn)Creeptest蠕變實(shí)驗(yàn)Impacttest沖擊試驗(yàn)Bendtest彎曲試驗(yàn)Hardnesstest硬度試驗(yàn)MaterialtestsTensiletest拉伸試TensiletestTensiletestTensiletestTensiletestTensiletestTensiletestFatigueTest疲勞試驗(yàn)SNcurveStressvs.NumberofcyclesFatigue/endurance忍耐limitEffectofstressconcentrations集中FatigueTest疲勞試驗(yàn)SNcurveFatigueTestFatigueTestCreep Plasticdeformationofamaterialwhichoccursasafunctionoftimewhenthematerialissubjectedtoconstant常數(shù)恒定不變的stressorload Normally正常的，和規(guī)則的associatedwith聯(lián)合elevatedtemperatureCreep PlasticdeformationofaCreep

Creep ImpacttestingMeasureofductility延展性Temperaturedependant受撫養(yǎng)者Izod懸臂式Charpy沙爾皮ImpacttestingMeasureofductiImpacttestingImpacttestingBendTestMeasureofductilityBendTestMeasureofductilityBendTestBendTestHardnesstestBrinell布氏Rockwell洛氏Vickers維氏Microhardness顯微硬度HardnesstestBrinell布氏BrinellHardnesstestBrinellHardnesstestRockwellHardnesstestRockwellHardnesstestVickersHardnesstestVickersHardnesstestVickersHardnesstestVickersHardnesstestShoreScleroscope肖氏硬度計(jì)Theshorescleroscopemeasureshardnessintermsoftheelasticityofthematerial.Adiamond-tippedhammerinagraduatedglasstubeisallowedtofallfromaknownheightonthespecimentobetested,andthehardnessnumberdependsontheheighttowhichthehammerrebounds;theharderthematerial,thehighertherebound.ShoreScleroscope肖氏硬度計(jì)TheshorShoreScleroscopeShoreScleroscopeASNTNDTLevelIIIbasictrai教學(xué)講解課件PhasediagramsandReactionsPhasediagramsandReactionsPhaseDiagramsPhaseDiagramsPhasereactionsMonotectic偏晶的，偏晶體 Liquid1=Liquid2+SolidPeritectic包晶體的，包晶體 Liquid+Solid1=Solid2Peritectoid轉(zhuǎn)熔體包晶的 Solid1+Solid2=NewSolid3PhasereactionsMonotectic偏晶的，PhasereactionsEutectic熔點(diǎn)最低的，共融的 Liquid=Solid1+Solid2Eutectoid共析體，共析的 Solid1=Solid2+Solid3PhasereactionsEutectic熔點(diǎn)最低的，PhasereactionPeritectic包晶體 Liquid+α=βPhasereactionPeritectic包晶體PhasereactionPeritectoid包析體

β+α→γPhasereactionPeritectoid包析體PhasereactionEutectic共融合金 Liquid=α+θPhasereactionEutectic共融合金PhasereactionEutectoid共析體 Solidα=β+γ

PhasereactionEutectoid共析體ASNTNDTLevelIIIbasictrai教學(xué)講解課件CoolingcurveforironCoolingcurveforironFe–Fe3CPhaseDiagramFe–Fe3CPhaseDiagramPhasesofFe–Fe3CFerriteAusteniteDeltaFerriteCementite滲碳體PhasesofFe–Fe3CFerriteAustenite Thisisthefacecenteredcubicstructureofsteel(GammaIron).Itisasolidstagestructurestable穩(wěn)定的，牢靠的onlyathightemperatures(910°C-1400°C). Candissolve分解融化upto2%Carbonduetothelargerinterstitial空隙的，間隙的openingsbetweentheatomsAustenite ThisisthefacecenAusteniteAusteniteFerrite Thisisabodycenteredcubicstructureofsteel.(AlphaIron).

Itisasolidstagestructurestableatroomtemperature–canonlyaccommodate調(diào)節(jié)0.008%Carbonatroomtemperatureand0.025%Carbonat723°CduetothesmallinterstitialopeningsFerrite ThisisabodycentereFerriteFerriteCementite Thisisacrystallinecompoundofironandcarbon(Fe3C)withanorthorhombic正交晶的crystalstructure.Itcontains6.67%Cbyweight.Cementite ThisisacrystallinTransformationProductsPearlite珠光體Martensite馬氏體Bainite貝氏體TransformationProductsPearlitPearlite CementiteandFerritejoininalamellar薄片狀formtoproducePearlite. NormallyresultsfromthetransformationofAusteniteduringslowcooling.Pearlite CementiteandFerritePearlitePearliteMartensite ThisstructureisobtainedwhenAusteniteisfastcooledandthus如此至此transformstobodycenteredtetragonal四角形的菱形的.Martensite ThisstructureisoMartensiteMartensiteBainite Austenitedecomposes分解腐爛toformFerriteandCarbide.FormsinthetemperatureregionbetweenwhereMartensiteandPearliteformsBainite Austenitedecomposes分解BainiteBainiteFe–Fe3CPhaseDiagramFe–Fe3CPhaseDiagramEutectoidReaction共析轉(zhuǎn)變Austenite?Ferrite+IronCarbideEquilibriumconditions平衡條件0.83%C@723°CFerrite+IronCarbide=PearliteCalculate估算計(jì)算phaseswithleverrule@0.83%CEutectoidReaction共析轉(zhuǎn)變AusteniPhaseQuantities? 0.025%__________________6.67%Fe3C

Λ0.83%?=6.67–0.83X100

6.67–0.025=88.4%Fe3C=100–88.4=11.6%PhaseQuantities? 0.025%______TimeTemperatureTransformation-DiagramTimeTemperatureTransformatioTTT–DiagramTTT–DiagramContinuousCoolingDiagramContinuousCoolingDiagramAlloying AnAlloyisasubstance物質(zhì)thathasmetallicpropertiesandiscomposedoftwoormorechemicalelements. Austenitestabilizers奧氏體穩(wěn)定劑

FerritestabilizersAlloying AnAlloyisasubstanPurposeofAlloyingIncreasehardenabilityImprovestrengthImprovemechanicalpropertiesateitherhighorlowtemperaturesImprovetoughness韌性Improvewearresistance耐磨性ImprovecorrosionresistanceImprovemagneticproperties.PurposeofAlloyingIncreasehaChemicalelementsinSteelCarbonManganese錳SiliconSulpherPhosphorous磷Nickel鎳ChromiumMolybdenumV,Ti,AlChemicalelementsinSteelCarbChemicalElementsinSteelCarbon(C)Upto2%IncreasehardnessandstrengthReducesweldabilityManganese(Mn)Upto1.5%IncreasehardenabilityBondswithSChemicalElementsinSteelCarbChemicalElementsinSteelSilicon(Si)Upto1%Deoxidizer去氧劑，還原劑IncreasestrengthSulphur(S)Undesirable–aslowaspossibleReduceweldabilityChemicalElementsinSteelSiliChemicalElementsinSteelPhosphorous(P)StrengthenslowcarbonsteelImprovesmachinabilityChromium(Cr)IncreaseoxidationresistanceIncreasehardenabilityResistsabrasionandwear腐蝕和耐磨ChemicalElementsinSteelPhosChemicalElementsinSteelMolybdenum(Mo)Upto1%Carbideformer碳化物形成者IncreasehardenabilityandstrengthatelevatedtemperatureNickel(Ni)IncreasetoughnessandhardenabilityCorrosionResistanceChemicalElementsinSteelMolyChemicalElementsinSteelAluminium(Al)Deoxidizerandgrainrefiner去氧劑和晶粒細(xì)化劑Alloyinnitridingsteels合金在氮化物Vanadium(V)GrainrefinerResiststemperingIncreasehardenabilityChemicalElementsinSteelAlumChemicalelementseffectonphasediagramNiandMnlowerscriticaltemperature降低臨界溫度Mo,Al,Si,WandVraiseslowercriticaltemperature提高臨界溫度ChemicalelementseffectonphASNTNDTLevelIIIbasictrai教學(xué)講解課件ModernSteelmakingModernSteelmakingSteelmakingOpenHearth平爐Bessemer酸性轉(zhuǎn)爐鋼Electricarc電弧SteelmakingOpenHearth平爐BlastFurnace高爐鼓風(fēng)爐BlastFurnace高爐鼓風(fēng)爐SteelmakingSteelmakingHeatTreatmentHeatTreatmentHeatTreatment Acombinationofheatingandcoolingoperations,timedandappliedtoametaloralloyinthesolidstateinawaythatwillproducedesiredproperties.HeatTreatment AcombinationoHeatTreatmentAnnealing退火鍛練Normalizing常態(tài)化，標(biāo)準(zhǔn)化，正火StressRelieving應(yīng)力消除HardeningandTempering硬化及退火HeatTreatmentAnnealing退火鍛練ASNTNDTLevelIIIbasictrai教學(xué)講解課件Annealing Heatingofsteeltotemperature(Austeniteregion)andslowcooling(furnace)throughthetransformationrangeStressrelievingGrainrefiningSofteningAnnealing HeatingofsteeltoAnnealing

Annealing Annealing

Annealing Normalizing正火 Heatingofsteeltotemperatureabovetheuppercriticalline(A3orAcm)andcoolinginstillairtoroomtemperature.GrainrefinementAlleviatechemicalsegregation緩和化學(xué)間隙SteelisharderandstrongerthanwhenannealedNormalizing正火 HeatingofsteeNormalizing

Normalizing Stressrelieving550–650°CNomajorchangesinmicrostructureStressrelieving550–650°CHardeningHeattoAusteniteregionFastcooling–QuenchinoilorwaterAustenitetransformstoMartensiteHardeningHeattoAusteniteregTempering HeatingofthehardenedsteeltosometemperaturebelowthelowercriticaltemperatureRelievesstressImprovesductilityandtoughnessReduceshardnessandstrengthTempering HeatingofthehardeTempering

Tempering EffectoftemperingonpropertiesReducesUTS極限抗拉強(qiáng)度ReducesYieldstrengthImproveselongation伸長ImprovesreductionofareaImprovesductility韌性EffectoftemperingonpropertHardeningHardeningSurfaceHeatTreatmentsCarburizing滲碳Nitriding氮化Carbonitriding(Cyaniding)碳化FlameHardening火焰表面硬化InductionHardening感應(yīng)淬火SurfaceHeatTreatmentsCarburiCarburizing/CaseHardeningLowcarbonsteel(%C<0.2)HardwearresistantouterlayerSolidmedia,saltbathorgasAtmosphereisCOrichCarburizing/CaseHardeningLoCarburizing/CaseHardeningTemperature=925°CDiffusionreaction散射Austenite(Fe)+2CO→CarbonenrichedAustenite+CO2MartensitetransformationoncoolingCarburizing/CaseHardeningTeCarburizing/CaseHardeningCarburizing/CaseHardeningNitridingFerriticthermochemicaltreatmentAl,Cr,Mo500-590°CDiffusionreactionNotransformationoncoolingNitridingFerriticthermochemiNitridingNitridingNitridingHighsurfacehardnessHighwearstrengthHightemperresistanceHightemperaturehardnessisgoodHighfatiguestrengthNitridingHighsurfacehardnessInductionhardeningElectriccoil–magneticfield–eddycurrents–heatmaterialLocalizedheatingandcooling%C>0.25InductionhardeningElectriccoInductionhardeningInductionhardeningInductionhardeningInductionhardeningFlameHardening Heatworkpiecewithflameanddirectquenchingoraircooling0.3>%C<0.6StressrelieveafterquenchingFlameHardening HeatworkpieceFlameHardening

FlameHardening ASNTNDTLevelIIIbasictrai教學(xué)講解課件CommonMaterialsCommonMaterialsSteelTypesLowCarbonSteel(0–0.25%C)MediumCarbonSteel(0.25–0.6%C)HighCarbonSteel(0.60–2.0%C)SteelTypesLowCarbonSteel(SteelTypesLowAlloySteelCastIron(2.0–6.67%C)StainlesssteelsSteelTypesLowAlloySteelLowCarbonsteelRelativelysoftEasilydeformedandshapedNails,Structuralshapes,pipe,wireLowCarbonsteelRelativelysofLowCarbonsteelMicrostructureLowCarbonsteelMicrostructurMediumCarbonsteelCanbehardenedbyquenchingCanbetemperedHigherstrengththanlowcarbonsteelsShafts,Axles,machinepartsMediumCarbonsteelCanbehardHighCarbonsteelCanbehardenedbyquenchingCanbetemperedHammers,Chisels,Drills,SpringsHighCarbonsteelCanbehardenLowAlloysteelMn,Ni,Cr,Mo,Cu,VQuenchedandTemperedIncreasedStrength,Ductility,FatigueresistanceandWearresistanceShafts,Gears,Torsionbars,Pins,Construction,TransportationLowAlloysteelMn,Ni,Cr,Mo,GalvanizedSteel鍍鋅鋼ZnrichcoatingCorrosionprotectionGalvanizedSteel鍍鋅鋼ZnrichcoHotDipGalvanizingHotDipGalvanizingCastirons2-6.67%CarbonWhitecastironMalleablecastironGreycastironNodularcastironCastirons2-6.67%CarbonWhiteCastIronAllcarboniscombined-Cementite2.5–4.3%C(Hypoeutectic)Si<1.3%WhiteCastIronAllcarboniscWhiteCastIronWhiteCastIronWhiteCastIronHardandwearresistantBrittleDifficulttomachineLinersformixersandmillsWhiteCastIronHardandwearrMalleableCastIron Carbonisuncombined–irregularroundparticlesHeattreatedwhitecastiron2–2.65%C0.9–1.4%SiMalleableCastIron CarbonisMalleableCastIronAxlesanddifferentialhousingsCrankshaftsMalleableCastIronAxlesanddGreyCastIron Carbonisuncombinedintheformofgraphiteflakes2.5–4.0%C1.5–5.0%SiGreyCastIron CarbonisuncomGreyCastIronGreyCastIronGreyCastIronHardnessisdeterminedbymicrostructureGearhousings,pumphousingFirehydrants,sewercoversGreyCastIronHardnessisdeteNodularCastIronDuctileorSGironCarbon/Graphite-spheroidsDuctileMotorframes,cylinderheads,crankshafts,pistons,millrollsNodularCastIronDuctileorSGNodularCastIronNodularCastIronStainlesssteelsFerriticMartensiticAusteniticDuplexPrecipitationhardeningStainlesssteelsFerriticFerriticStainlesssteel14–27%Cr–LowCMagneticCannotbehardenedbyheattreatment441,430,409ColdformeasilyFerriticStainlesssteel14–2FerriticStainlesssteelBrittlePoorweldabilityGraingrowthGrainboundaryembrittlementNitricacidtanks,furnaceparts,annealingbaskets,decorativeFerriticStainlesssteelBrittlAusteniticStainlesssteel18/8types18–25%Cr,8-14%Ni,0-3%MoNonMagneticCannotbehardenedbyheattreatmentAusteniticStainlesssteel18/8AusteniticStainlesssteelAusteniticStainlesssteelAusteniticStainlesssteelColdworked–workhardens304,308,316,310Shockresistant,GoodweldabilityPulphandling,boilershells,foodandchemicalhandling,heattreatmentequipmentAusteniticStainlesssteelColdMartensiticStainlesssteel0.15–1.2%C,1.5–18%Cr410,420,431MagneticCanbehardenablebyheattreatmentMartensiticStainlesssteel0.1MartensiticStainlesssteelPoorweldabilityControlledpre/postheatingTurbine,pumpshafts,cutlery,surgicalinstruments,valvesMartensiticStainlesssteelPooDuplexstainlesssteel0.03–0.06%C,19–28%Cr,1–8%Ni,0.5–4%Mo,0.1–0.35%N,0.05–2.5%Cu2205,2507FerriteandaustenitemicrostructureDuplexstainlesssteel0.03–0DuplexstainlesssteelDuplexstainlesssteelDuplexstainlesssteelImprovedintergranular,andpittingcorrosionresistanceImprovedstresscorrosioncrackingresistanceChemicalprocessing,OilandGasindustryDuplexstainlesssteelImprovedPrecipitationhardeningstainlesssteel17-4PH,17-7PH15-17%Cr,4–10%Ni,Cu,AlTemperedMartensitewithagehardenedprecipitatesPumps,rocketcasingsNopreheatbutpostweldheattreatmenttorestorepropertiesPrecipitationhardeningstainlAluminiumPureAlAl-Cu 2xxxAl-Mn 3xxxAl-Si 4xxxAl-Mg 5xxxAl-Mg-Si 6xxxAl-Zn 7xxxAluminiumPureAlCopperPurecopperBrass(Cu+Zn)Bronze(Cu+Sn;Si;Al;Be)CupronickelCopperPurecopperPlasticsMonomer–polymerization–plasticThemoplasticThermosetPlasticsMonomer–polymerizatiManufacturingProcessesCastingWeldingRollingExtrusionPressingDrawingManufacturingProcessesCastingCastingObtainGeometryPatternmakingCoremakingMoldingMeltingandpouringCleaningCastingObtainGeometryCastingCastingVacuumDieCastingVacuumDieCastingCastingCastingCastingDefectsMetallicprojections - JointFlashorFinsCavities - BlowholesandpinholesDiscontinuities - HotcrackingSurfaceDefects - FlowmarksIncompletecastings- PouredshortIncorrectdimensionandshapeMetallicinclusionsCastingDefectsMetallicprojecCastingDefectsCastingDefectsPipemakingPipemakingPowderMetallurgyPowderMetallurgyPowderMetallurgyPowderMetallurgyExtrusionExtrusionExtrusionExtrusionExtrusionExtrusionHotRollingHotRollingRollingRollingProfilesProfilesForgingForgingClosedDieForgingClosedDieForgingOpenDieForgingOpenDieForgingForgingDefectsStartingMaterialSeamsandlapsInternalCracksForgingProcessSurfacecracksDecarburizationPorosityForgingDefectsStartingMateriForgingDefectsForgingDefectsDrawingDrawingDeepDrawingDeepDrawingStampingStampingPressingPressingWeldingProcessesWeldingProcessesWeldingProcessesArcweldingElectricresistanceheatingElectronbeamPlasmaarcFrictionweldingWeldingProcessesArcweldingWeldingProcessesUltrasonicweldingElectroslagExplosionweldingDiffusionweldingWeldingProcessesArcweldingprocessesShieldedMetalArcWelding(SMAW)GasMetalArcWelding(GMAW)FluxCoredArcWelding(FCAW)SubmergedArcWelding(SAW)GasTungstenArcWelding(GTAW)ArcweldingprocessesShieldedShieldedMetalArcWeldingShieldedMetalArcWeldingShieldedMetalArcWeldingFerrousandNonferrousBasemetalsLowCarbonCoreWireCarbonates,Rutile,Fluorides,Metalalloys,CelluloseandSilicateBindersShieldedMetalArcWeldingFerrShieldedMetalArcWeldingFluxCoatingFunctionsArcstabilizationGasshield–removeairSlag–protect,supportandinsulateAlloyingDeoxidersandfluxingagentsElectricalcharacteristicsShieldedMetalArcWeldingFluxShieldedMetalArcWeldingSelectinganelectrodeWeldingPositionWeldingcurrentJointdesignandfit-upServiceconditionsProductionefficiencyShieldedMetalArcWeldingSeleShieldedMetalArcWeldingProcessvariablesAmperageVoltageOCVArclengthSkilllevelShieldedMetalArcWeldingProcShieldedMetalArcWeldingAdvantagesVersatileManyelectrodetypesAllpositionsRangeofthicknessesLowstart-upcostEasytouseShieldedMetalArcWeldingAdvaShieldedMetalArcWeldingDisadvantagesLowdepositionrate(1–8kg/hour)HighlabourandconsumablecostShieldedMetalArcWeldingDisaElectrodeclassificationAWSElectrodeclassificationER70XX-YElectrodeclassificationAWSElGasMetalArcWeldingGasMetalArcWeldingGasMetalArcWeldingFerrousandNonferrousbasemetalCarbon,alloysteelandnonferrouswireGasshieldCO2,Argon,Mixedgas(Ar,O2,H2,He,CO2)Spray,Globular,ShortCircuitTransfermodesGasMetalArcWeldingFerrousaGasMetalArcWeldingProcessVariablesAmperageVoltageTravelspeedElectrodeextensionShieldinggasGasMetalArcWeldingProcessVGasMetalArcWeldingGasSelectionAL UseAr; T>15mmUseAr+HeSteel CO2;Ar,Ar+O