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1SHEETMETALFORMINGOFMAGNESIUMWROUGHTMAGNESIUMWROUGHTALLOYSFORMABILITYANDPROCESSTECHNOLOGYABSTRACTNEWDEVELOPMENTSATTHEFORMETALFORMINGANDMETALFORMINGMACHINETOOLSSHOWTHATMAGNESIUMSHEETSPOSSESSEXCELLENTFORMINGBEHAVIOR,IFTHEPROCESSISCONDUCTEDATELEVATEDTEMPERATURESFORTHEEVALUATIONOFMECHANICALPROPERTIESRELEVANTFORFORMINGOFMAGNESIUMSHEETS,UNIAXIALTENSILETESTSHAVEBEENCARRIEDOUTATVARIOUSTEMPERATURESANDSTRAINRATESDEEPDRAWINGTESTSWITHMAGNESIUMALLOYSAZ31B,AZ61B,ANDM1SHOWVERYGOODFORMABILITYINATEMPERATURERANGEBETWEEN200AND2508CBESIDESTEMPERATURE,THEINFLUENCEOFFORMINGSPEEDONLIMITDRAWINGRATIOHASBEENINVESTIGATEDTHEOBTAINEDRESULTSLEADTOTHECONCLUSIONTHATITISPOSSIBLETOSUBSTITUTECONVENTIONALALUMINUMANDSTEELSHEETSBYUSINGMAGNESIUMSHEETMETALWROUGHTALLOYS1INTRODUCTIONINORDERTOREDUCEFUELCONSUMPTION,GENERALEFFORTSHAVEBEENMADETODECREASETHEWEIGHTOFAUTOMOBILECONSTRUCTIONSBYANINCREASEDUSEOFLIGHTWEIGHTMATERIALSINTHISFRAMEWORK,MAGNESIUMALLOYSAREOFSPECIALINTERESTBECAUSEOFTHEIRLOWDENSITYOF174G/CM3PRESENTLY,MAGNESIUMALLOYSFORTHEUSEASAUTOMOBILEPARTSAREMAINLYPROCESSEDBYDIECASTINGTHEDIECASTINGTECHNOLOGYALLOWSTHEMANUFACTURINGOFPARTSWITHCOMPLEXGEOMETRYHOWEVER,THEMECHANICALPROPERTIESOFTHESEPARTSOFTENDONOTMEETTHEREQUIREMENTSCONCERNINGTHEMECHANICALPROPERTIESEGENDURANCESTRENGTHANDDUCTILITYAPROMISINGALTERNATIVEHASTOBESEENINCOMPONENTSTHATAREMANUFACTUREDBYFORMINGPROCESSESTHEPARTSMANUFACTUREDBYTHISTECHNOLOGYARECHARACTERIZEDBYADVANTAGEOUSMECHANICALPROPERTIESANDFINEGRAINEDMICROSTRUCTUREWITHOUTPORES1HOWEVER,AWIDESPREADUSEOFFORMINGTECHNOLOGIESFORTHEPROCESSINGOFMAGNESIUMALLOYSISRESTRICTEDBECAUSEOFINSUFFICIENTKNOWLEDGEABOUTTHEFORMINGTECHNOLOGIESANDSUITABLEPROCESSPARAMETERSTHATHAVETOBEAPPLIED2,3AUTOMOTIVEBODYCONSTRUCTIONSOFFERAGREATPOTENTIALFORTHEAPPLICATIONOFMAGNESIUMSHEETMETALCOMPONENTSINGENERAL,THEAUTOMOTIVEBODYCOMPLETELYCONSISTSOFSHEETMETALPARTSANDREPRESENTSASHAREOFABOUT25OFTHEENTIREVEHICLEMASSTHEREFORE,THESUBSTITUTIONOFCONVENTIONALSHEETMATERIALSBYMAGNESIUMSHEETSWOULDLEADTOESSENTIALWEIGHTSAVINGSINTHISAPPLICATION22PLASTICMATERIALPROPERTIESOFMAGNESIUMSHEETSMAGNESIUMALLOYSSHOWALIMITEDFORMABILITYATROOMTEMPERATURETHISRESULTSFROMTHEFACTTHATTHEHEXAGONALCRYSTALSTRUCTUREANDTHELOWTENDENCYTOTWINNINGONLYALLOWLIMITEDDEFORMATIONSTHEDIFFERENTLYORIENTATEDCRYSTALLITESONLYSHOWADEFORMATIONONTHEINDIVIDUALBASESLIPPLANE,WHICHLEADSTOAMUTUALSLIPHINDRANCE4,5ACONSIDERABLEIMPROVEMENTOFTHEFORMINGQUALITIESCANBEACHIEVEDBYAPPLYINGTEMPERATURETHECONSIDERABLEINCREASEINFORMABILITYTHATOCCURSINTHETEMPERATURERANGEFROM200TO2258CDEPENDINGONALLOYINGCOMPOSITIONWASINVESTIGATEDBYSIEBEL6THEREASONFORTHISEFFECTWASFOUNDINTHETHERMALACTIVATIONOFPYRAMIDSLIDINGPLANESINTHEHEXAGONALSTRUCTURE721INFLUENCEOFFORMINGTEMPERATUREONFLOWSTRESSADETAILEDEVALUATIONOFTHEDEFORMATIONPROPERTIESOFMAGNESIUMSHEETSREQUIRESTHEDETERMINATIONOFTHEMATERIALSCHARACTERISTICVALUESLIKEANISOTROPYORFLOWCURVES8,9BECAUSESYSTEMATICINVESTIGATIONSINTHISAREAARENOTAVAILABLE,EXTENSIVEINVESTIGATIONSCONCERNINGTHEINFLUENCEOFTEMPERATUREANDSTRAINRATEONPLASTICPROPERTIESOFVARIOUSMAGNESIUMALLOYSWEREPERFORMEDATINSTITUTEFORMETALFORMINGANDMETALFORMINGMACHINETOOLSIFUMFIG1DISPLAYSFLOWCURVESOFMAGNESIUMSHEETMATERIALAZ31BATDIFFERENTTEMPERATURES,DETERMINEDINTHEUNIAXIALTENSILETESTACCORDINGTOEN10002,PART5ITISOBVIOUSTHATTHESTRESSESANDPOSSIBLESTRAINSLARGELYDEPENDONTHEFORMINGTEMPERATURETHEDECREASEOFFLOWSTRESSESINTHETEMPERATURERANGEABOVE2008CATTRIBUTESTOTEMPERATUREDEPENDENTRELAXATION33DEEPDRAWINGOFMAGNESIUMALLOYSINORDERTOINVESTIGATETHEFORMABILITYOFMAGNESIUMSHEETS,DEEPDRAWINGTESTSATDIFFERENTFORMINGTEMPERATURESWERECARRIEDOUTATIFUMWITHACYLINDRICALTOOLSYSTEMFIG3SHOWSTHERESULTSOFDEEPDRAWINGTESTSATATEMPERATUREOF50CWHEREASTHEDEEPDRAWINGOFTHEALLOYAZ31BUSINGALOWDRAWINGRATIOOFB0145WASPOSSIBLEDRAWINGDEPTH30MM,THEALLOYSAZ61BANDM1SHOWEDEARLYFRACTUREUSINGDRAWINGRATIOOFB016,AZ31BSHOWEDFRACTURESIMILARTOAZ61BANDM1THESETESTSCONFIRMTHELOWFORMABILITYOFMAGNESIUMALLOYSATLOWTEMPERATUREHOWEVER,THEINVESTIGATEDMAGNESIUMALLOYSSHOWVERYGOODFORMABILITYATHIGHERTEMPERATURE，THEMAXIMUMLIMITDRAWINGRATIOOFB0MAX252WASDETECTEDFORAZ31BATAFORMINGTEMPERATUREOF2008CAZ61BANDM1SHOWMAXIMUMVALUESOFAPPROXIMATELYB0MAX220UPTO225THEVALUESOFTHEALUMINUMALLOYALMG45MN04AREDISPLAYEDFOR4COMPARISONDUETOTHEGOODFORMABILITYOFTHEALUMINUMALLOYATROOMTEMPERATURE,THEINCREASEINLIMITDRAWINGRATIOWITHRISINGTEMPERATUREISLOWCOMPAREDTOTHEMAGNESIUMALLOYSTHERESULTSGAINEDFROMTHETENSILETESTSSHOWEDTHESIGNIFICANTINFLUENCEOFSTRAINRATEONTHEMECHANICALPROPERTIESOFMAGNESIUMALLOYS1HKEHLERETAL,PARTIKELVERSTARKTELEICHTMETALLE,METALLBAND,49,HEFT3,19952EDOEGE,KDRODER,STJANSSEN,LEICHTBAUMITMAGNESIUMKNETLEGIERUNGENBLECHUMFORMUNGUNDPRAZISIONSSCHMIEDENTECHNISCHERMGLEGIERUNGEN,WERKSTATTSTECHNIK,BAND88,HEFT11/12,19983EDOEGE,KDRODER,FPHAMM,SHEETMETALFORMINGOFMAGNESIUMALLOYS,PROCEEDINGSOFTHEIMACONFERENCEONMAGNESIUMMETALLURGY,CLERMONTFERRAND,FRANCE,OCTOBER19964HJBARGEL,GSCHULZE,WERKSTOFFKUNDE,VDIVERLAGGMBH,DUSSELDORF,19885CSROBERTS,MAGNESIUMANDITSALLOYS,WILEY,NEWYORK,19606GSIEBEL,INBECKED,TECHNOLOGYOFMAGNESIUMANDITSALLOYS,HUGHES,LONDON,19407NNMAGNESIUMANDMAGNESIUMALLOYS,ULLMANNSENCYCLOPEDIAOFINDUSTRIALCHEMISTRY,REPRINTOFARTICLESFROM5THEDITION,VCH,WEINHEIM,19908EDOEGE,KDRODER,PROCESSINGOFMAGNESIUMSHEETMETALSBYDEEPDRAWINGANDSTRETCHFORMING,MATTECH78199719239EDOEGE,KDRODER,STJANSSEN,UMFORMENVONMAGNESIUMWERKSTOFFEN,DGMFORTBILDUNGSSEMINAR,CLAUSTHALZELLERFELD,OKTOBER1998,PP283010LTAYLOR,HEBOYER,INEADURAND,ETALEDS,METALSHANDBOOK,8THEDITION,VOL4,AMERICANSOCIETYOFMETALS,OL4,AMERICANSOCIETYOFMETALS,CLEVELAND,OH,196911KSIEGERT,ETAL,SUPERPLASTISCHEALUMI