Stress22pipi.com

MaterialDataSheetNo.
4050June2010EditionVDMCrofer22HCrofer22H*2Crofer22H*isahigh-temperatureferriticstainlesssteelespeciallydevelopedforapplicationinsolidoxidefuelcells(SOFC).
IthasgoodcreepstrengthbecauseofLavesphaseprecipitates.
Attemperaturesupto900°C(1652°F)achromium-manganeseoxidelayerisformedonthesurfaceofCrofer22H,whichisthermodynamicallyverystableandpossesseshighelectricalconductivity.
Thelowcoefficientofthermalexpansionismatchedtotheoneofceramicstypicallyusedforhightemperaturefuelcellsintherangeofroomtemperatureupto900°C(1652°F).
Crofer22Hischaracterizedby:excellentcorrosionresistanceathightemperaturesinanodegasandcathodegasgoodcreeppropertieslowrateofchromiumvaporizationeaseofworkingandprocessinglowcoefficientofthermalexpansiongoodelectricalconductivityoftheoxidelayerDesignationsandstandardsSpecificationCountryNationalstandardsMaterialdesignationChemicalcompositionSheet&PlateStripDDINENW.
-Nr.
1.
4755X1CrWNbTiLa22-2Table1-Designationsandstandards.
ChemicalcompositionCrFeCNSMnSiAlWNbTiLaPNiCumin.
20.
00.
101.
00.
200.
020.
04max.
24.
0bal.
0.
0300.
040.
0060.
800.
600.
103.
01.
000.
200.
200.
0500.
500.
50Table2–Chemicalcomposition(wt.
-%).
*ThyssenKruppVDMGmbHproducesCrofer22HunderlicenseofForschungszentrumJülich.
Crofer22H3PhysicalpropertiesDensityMeltingrange7.
8g/cm1452°C(Solidus)-1503°C(Liquidus)0.
278lb/in.
32646°F(Solidus)-2737°F(Liquidus)Temperature(T)ElectricalresistivityThermalconductivitySpecificheatCoefficientofthermalexpansionbetween20°C/68°FandTModulusofelasticity°C°Fcmcircmilft__W__mK_Btuin.
fth°F__J__kgK_Btu_lb°F10-6K10-6°FGPa103ksi20685633720.
01394690.
11220830.
21002126539120.
61434940.
1189.
85.
520730.
02003927444521.
51495320.
12710.
15.
720329.
33005728249310.
55.
819628.
44007528953522.
61576150.
14710.
86.
019027.
65009329657711.
06.
118226.
4600111210362025.
41769480.
22611.
26.
217525.
4700129210764411.
46.
3800147210965626.
11816600.
15811.
86.
6900165211166812.
36.
81000183211368029.
92076740.
16112.
87.
1Table3–Typicalphysicalpropertiesatroomandelevatedtemperatures.
Mechanicalproperties0.
2%YieldstrengthRp0.
2TensilestrengthRmElongationAHardnessHVMPaksiMPaksi%(Forinformationonly)Strip=320=46.
4=450=65.
3A50=18160–200Sheet&Plate=320=46.
4=450=65.
3A5=18A5=8**Thickness:>16mm(0.
630")Table4-Minimummechanicalpropertiesinthesolutionannealedconditionforallproductformsatroomtemperature.
Crofer22H4Product0.
2%YieldstrengthRp0.
2TensilestrengthRmElongationAMPaksiMPaksi%Strip39065.
656081.
223(A50)Sheet&Plate≤16mm>16mm39039065.
665.
652049075.
471.
125(A5)10(A5)Table5-Typicalmechanicalpropertiesfordifferentproductformsatroomtemperature.
TemperatureT0.
2%YieldstrengthRp0.
2TensilestrengthRmElongationA5°C°FMPaksiMPaksi%600111216023.
233348.
325700129211917.
314721.
3248001472497.
1558.
080Table6-Typicalmechanicalpropertiesforplate(12mm)athightemperatures.
Fig.
1-Typicalshort-timemechanicalpropertiesCrofer22H,12mmplate,asafunctionoftemperature(solutionannealedandabout2hoursattestingtemperaturebeforethetest)incomparisontoCrofer22APU.
Fig.
2-Stress-StraincurvesforCrofer22Hatvarioustemperatures.
Figure1showsthatCrofer22HclearlyhasahighertensilestrengththanCrofer22APU.
Crofer22Halsohasanincreasedcreepresistanceasshownbystress-rupturetestsinFigure3.
020406080100120140160180200550600650700750800850Temperature,°CYieldstrengthRp0.
2,MPaCrofer22HCrofer22APU010020030040050060001020304050607080Strain,%Stress,PMa20°C200°C400°C600°C700°C800°CCrofer22H5Fig.
3–Typicalcreep-rupturestrengthofsolutionannealedCrofer22H,12mmplate,inairincomparisontoCrofer22APU.
(AfterB.
Kuhnetal.
,ForschungszentrumJülich)Fig.
4-Typicalcreepstrain-timecurvesofsolutionannealedCrofer22Hinair.
Allcurvesarefromacontinuouselongationmeasurementatthesampleexcept*),whichisfromdiscontinuouselongationmeasurement(AfterB.
Kuhnetal.
,ForschungszentrumJülich)MetallurgicalstructureCrofer22Hhasabody-centered-cubicstructure.
Duringannealingattemperaturesuptoabout1000°C(1832°F)aLavesphaseisformedwhichincreasescreepstrength.
CorrosionresistanceCrofer22HshowsexcellentcorrosionresistanceinatmospheresrelevanttoSOFCapplicationsupto900°C.
TheoxidelayerofCrofer22APUconsistsofafinegrainedinnerscalewhichispredominantlyCr2O3andacolumnar(Mn,Cr)3O4spinelouteroxidelayer.
Figure5showsthecorrosionresistanceofCrofer22Hinairat800°Cforacommercialheat.
Forcomparisontheresultsofalaboratoryheatmeltedwithhigh-puritypre-materialspriortothecommercialheatarealsoincludedinFigure5.
Fig.
5-Masschangeduringdiscontinuousoxidationtests(100hcycles)ofacommerciallyproducedCrofer22Hheatinairat800°Casafunctionoftime.
Forcomparisonalaboratorymelt(250hcycles)isincluded(typicalvalues).
(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)110100110100100010000Timeatrupture,hStress,MPaCrofer22APUCrofer22H800°C,air0.
1110100110100100010000Time,hCreepstrain,%Crofer22H25MPa20MPa10MPa*)800°C00.
10.
20.
30.
40.
50.
6020040060080010001200Time,hWeightchange,mg/cmLaboratoryheatCommercialheat800°CCrofer22H6Fig.
6-Masschangeafter1110hoursofdiscontinuousoxidationtests(100hcycles)inairat800°CofsampleswithvaryingthicknessfromCrofer22HandCrofer22APU(typicalvalues).
(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Fig.
7-Masschangeduringdiscontinuousoxidationtests(250hcycles)ofcommerciallyproducedCrofer22HandCrofer22APUinairat800°Casafunctionoftime.
(typicalvalues)(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Fig.
8-Masschangeduringdiscontinuousoxidationtests(250hcycles)ofcommerciallyproducedCrofer22Hinairat800°Casafunctionoftime.
(typicalvalues)(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Fig.
9-Masschangeafter1000hoursofcyclicoxidationtestsinairat900°C(cyclesof2hand15min.
cooling)ofsampleswithvaryingthicknessfromcommerciallyproducedCrofer22HandCrofer22APU(typicalvalues).
(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Figure6clearlyshowsthatthethicknessofsheetmaterialhasnosignificanteffectonthecorrosionresistanceofCrofer22Hafter1110hat800°Cinair.
ThereisasignificanteffectontheoxidationresistanceofCrofer22APU.
Figure7showslongtermresultsofCrofer22HandCrofer22APU(firstcommercialmeltandaheatfromcurrentproduction,whichisrestrictedinresidualelements),whichclearlyshowstheexcellentcorrosionresistanceofCrofer22H.
0123450.
51.
02.
50.
51.
02.
5Initialspecimenthickness,mmWeightchangeafter1000h,mg/cmCrofer22APUCrofer22H900°C0.
00.
51.
01.
505001000150020002500Time,hWeightchange,mg/cmCrofer22APU(2-2.
5mm)800°CFirstcommercialheatcurrentheatCrofer22H(1mm)0.
00.
51.
01.
50.
51.
02.
50.
30.
51.
02.
5Initialspecimenthickness,mmWeightchangeafter1110h,mg/cmCrofer22APUCrofer22H800°C0.
00.
51.
01.
52.
02.
5020004000600080001000012000Time,hWeightchange,mg/cmCrofer22H0.
3mm0.
5mm1mm800°CCrofer22H7Fig.
10-Masschangeduringdiscontinuousoxidationtests(100hcycles)ofcommerciallyproducedCrofer22HandCrofer22APUinArgon4%H220%H2Oat800°Cforasheetthicknessof2,5mmasafunctionoftime(typicalvalues).
(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Fig.
11-Masschangeafter1000hoursofdiscontinuousoxidationtests(100hcycles)invariousgasesat800°CofcommerciallyproducedCrofer22HandCrofer22APUforasheetthicknessof1mm(typicalvalues).
(AfterQuadakkers,Niewolaketal.
,ForschungszentrumJülich)Figure8showslongtermresultsofCrofer22Hfordifferentthicknesses.
For0.
3mmthicknessafterabout3000hat800°Cinair,corrosionincreasesincomparisonto0.
5mmand1mmthickness.
AsshowninFigure9thethicknessofsheetmaterialhasalsonosignificanteffectonthecorrosionresistanceofCrofer22Hat900°Cinairupto1000hours.
ThereisasignificanteffectontheoxidationresistanceofCrofer22APU.
Figure10showslongtermresultsofCrofer22HandCrofer22APU(currentproduction)inArgon4%H220%H2Oat800°C,whichclearlyshowstheexcellentcorrosionresistanceofCrofer22H.
Figure11showsthecorrosionresistanceofCrofer22HandCrofer22APUat800°Cinvariousgases,whichagaindemonstratestheexcellentcorrosionresistanceofCrofer22H.
0.
00.
51.
01.
5Weightchangeafter1000h,mg/cm800°CArgon4%H220%HOAirArgon4%H210%COArgon4%H210%CO2%HOCrofer22HCrofer22APUArgon4%H220%H2OAirArgon4%H210%COArgon4%H210%CO2%H2O0.
00.
51.
01.
501000200030004000500060007000Time,hWeightchange,mg/cmCrofer22HCrofer22APU800°CCrofer22H8ApplicationsCrofer22Hisusedforinterconnectorplatestoseparateindividualplatesinsolidoxidefuelcells(SOFC).
FabricationandheattreatmentCrofer22Hcanbehotandcoldworkedandmachined.
HeatingProductionpiecesmustbecleanandfreefromallkindsofcontaminantsbeforeandduringanyheatingoperation.
Crofer22Hmaybecomeembrittledifheatedinthepresenceofcontaminantssuchassulfur,phosphorus,leadandotherlow-melting-pointmetals.
Sourcesofsuchcontaminantsincludemarkingandtemperature-indicatingpaintsandcrayons,lubricatinggrease,fluidsandfuels.
Fuelsmustbeaslowinsulfuraspossible.
Naturalgasshouldcontainlessthan0.
1wt.
-%sulfur.
Liquidfuelswithasulfurcontentnotexceeding0.
5wt.
-%aresuitable.
Duetotheirclosecontroloftemperatureandlackofcontamination,thermaltreatmentsinelectricfurnacesundervacuumorinaninertgasatmospherearetobepreferred.
Treatmentsinanairatmosphereand,alternatively,ingas-firedfurnacesareacceptablethough,ifcontaminantsarekeptatlowlevelssothataneutralorslightlyoxidizingfurnaceatmosphereisattained.
Afurnaceatmospherefluctuatingbetweenoxidizingandreducingconditionsmustbeavoidedaswellasdirectflameimpingementonthemetal.
ColdworkingForcoldworkingthesolutionannealedconditionisrecommended.
HeattreatmentAsolutionannealingcanbeperformedattemperaturestypicallyabove1050°C(1922F),followedbyfastcoolingwithairoraprotectiveatmosphere.
Aftercoldformingarecrystallizationheattreatment,typicallyabove1050°C,isrequired.
DescalingandpicklingOxidesofCrofer22Handdiscolorationadjacenttoweldsaremoreadherentthanonstandardstainlesssteels.
Grindingwithveryfineabrasivebeltsordiscsisrecommended.
Careshouldbetakentopreventtarnishing.
Beforepicklingwhichmaybeperformedinanitric/hydrofluoricacidmixturethesurfaceoxidelayermustbebrokenupbyabrasiveblasting,bycarefullyperformedgrindingorbypretreatmentinafusedsaltbath.
Particularattentionshouldbepaidtothepicklingtimeandtemperature.
WeldingWhenweldingnickelalloysandhighalloyedstainlesssteels,thefollowinginstructionsshouldbeadheredto:WorkplaceTheworkplaceshouldbeinaseparatelocation,wellawayfromareaswherecarbonsteelfabricationtakesplace.
Maximumcleanlinessandavoidanceofdraughtsareparamount.
Auxiliaries,clothingCleanfineleatherglovesandcleanworkingclothesshouldbeused.
ToolsandmachinesToolsusedfornickelalloysandhighalloyedstainlesssteelsmustnotbeusedforothermaterials.
Brushesshouldbemadeofstainlessmaterials.
Fabricatingandworkingmachinerysuchasshears,pressesorrollersshouldbefittedwithmeans(felt,cardboard,plasticsheeting)ofavoidingcontaminationofthemetalwithferrousparticles,whichcanbepressedintothesurfaceandthusleadtocorrosion.
CleaningCleaningofthebasemetalintheweldarea(bothsides)andofthefillermetal(e.
g.
weldingrod)shouldbecarriedoutwithACETONE.
Trichlorethylene(TRI),perchlorethylene(PER),andcarbontetrachloride(TETRA)mustnotbeusedastheyaredetrimentaltohealth.
EdgepreparationThisshouldpreferablybedonebymechanicalmeansbyturning,millingorplaning;abrasivewaterjetorplasmacuttingisalsosuitable.
However,inthelattercasethecutedge(thefacetobewelded)mustbefinishedoffcleanly.
Carefulgrindingwithoutoverheatingispermitted.
StrikingthearcThearcshouldonlybestruckintheweldarea,i.
e.
,onthefacestobeweldedoronarun-outpiece.
Strikingmarksleadtocorrosion.
Crofer22H9WeldingprocessCrofer22Hinthinthicknesses(=1.
5mm/0.
06in.
)canbejoinedtoitselfbyGTAW(TIG)withouttheuseoffillermetal.
Itcanalsobejoinedbyspotweldingorroll-seamwelding.
Forwelding,Crofer22Hshouldbeinthesolutionannealedconditionandshouldbefreefromscale,greaseandmarkings.
Argon4.
8isrecommendedforshieldinggasaswellasforrootbacking.
Ahydrogenand/ornitrogencontaininggasshouldbeavoided.
Anyheattintshouldberemovedpreferablybybrushingwithastainlesssteelwirebrushwhiletheweldmetalisstillhot.
Weldingparametersandinfluences(heatinput)Careshouldbetakenthattheworkisperformedwithadeliberatelychosen,lowheatinput.
Theheatinputperunitlengthshouldnotexceed8kJ/cm.
Postweldtreatment(brushing,picklingandthermaltreatments)Brushingwithastainlesssteelwirebrushimmediatelyafterwelding,i.
e.
,whilethemetalisstillhot,generallyresultsinremovalofheattintandproducesthedesiredsurfaceconditionwithoutadditionalpickling.
Forpicklingrefertotheinformationunder"Descalingandpickling"Neitherpre-norpostweldthermaltreatmentsarenormallyrequired.
AvailabilityCrofer22Hisavailableassheet&plateandstrip.
Sheet&Plate(forcut-to-lengthavailability,refertostrip)Conditions:hotorcoldrolled(hr,cr),soft-annealedandpickledThicknessmmhr/crWidth1)mmLength1)mm1.
10-0.
10-≤0.
254-0.
25-≤0.
66-0.
60-≤1.
08-1.
0-≤2.
015-2.
0-≤3.
0)-≤3.
5)25-0.
004-≤0.
0100.
16-144)121620>0.
010-≤0.
0240.
24-30162024>0.
024-≤0.
0400.
32-30162024>0.
040-≤0.
0800.
60-30162024>0.
080-≤0.
120)-≤0.
140)1.
00-301620241)Cut-to-lengthavailableinlengthsfrom10to158in.
2)Maximumthickness:brightannealed–0.
120in.
coldrolledonly–0.
140in.
3)Widerwidthssubjecttospecialenquiry4)Widerwidthsupto29in.
subjecttospecialenquiryTheinformationcontainedinthisdatasheetisbasedonresultsofresearchanddevelopmentworkanddatalistedinapplicablespecificationsandstandardsavailableandineffectatthetimeofprinting.
Itdoesnotprovideanyguaranteeofparticularcharacteristicsorfit.
ThyssenKruppVDMreservestherighttomakechangeswithoutnotice.
ThedatasheethasbeencompiledtothebestknowledgeofThyssenKruppVDMandisgivenwithoutanyliabilityonthepartofThyssenKruppVDM.
ThyssenKruppVDMisonlyliableaccordingtothetermsofthesalescontract,andinparticulartotheGeneralConditionsofSalesincaseofanydeliveryfromThyssenKruppVDM.
AsupdatesofdatasheetsarenotautomaticallysendoutwhenissuedThyssenKruppVDMrecommendstorequestthelatesteditionofrequireddatasheetseitherbyphone+49239255-2588,byfax+49239255-2596,orbyemailundervdm@thyssenkrupp.
com.
CurrentissuesofbrochuresanddatasheetsarealsoavailableontheInternetunderwww.
thyssenkruppvdm.
comJune2010Edition.
ImprintVDMMetalsGmbHPlettenbergerStrae258791WerdohlGermanyPhone+49(0)239255-0Fax+49(0)239255-2217vdm@vdm-metals.
comwww.
vdm-metals.
comDateofpublicationJune2010PublisherVDMMetalsGmbHPlettenbergerStrae258791WerdohlGermanyDisclaimerAllinformationcontainedinthisdatasheetarebasedontheresultsofresearchanddevelopmentworkcarriedoutbyVDMMetalsGmbH,andthedatacontainedinthespecificationsandstandardslistedavailableatthetimeofprinting.
Theinformationdoesnotrepresentaguaranteeofspecificproperties.
VDMMetalsreservestherighttochangeinformationwithoutnotice.
Allinformationcontainedinthisdatasheetiscompiledtothebestofourknowledgeandisprovidedwithoutliability.
DeliveriesandservicesaresubjectexclusivelytotherelevantcontractualconditionsandtheGeneralTermsandConditionsissuedbyVDMMetalsGmbH.
Useofthemostup-to-dateversionofthisdatasheetistheresponsibilityofthecustomer.