外文翻译--一种新型的基于超磁伸缩材料的超磁致伸.pdf

sensorLiu,Keywords:InversemagnetostrictiveeffectForcesensorGiantmagnetostrictivematerialrodmagnetostrictiveAHallexpoundedfirstly.ThemagneticcharacteristicsareanalyzedbyFEM.AmodelisdevelopedIfepects,suchascorematerialandexcitingmodeisthefocusofthisresearch.Atpresent,thesensitivematerialcom-measureisneeded.Theemergenceofgiantmagnetostrictivematerial(GMM)providesanewtypeofsensitivematerialforthedevelopmentofmagnetostrictiveforcesensor.Byrightofitsexcellentcharacteristicsoflargemagnetostrictivecoeffi-cientatroomtemperature(1500C210C062000C210C06)whichis1001000timeshigherthanthatofcommonmag-netostrictivematerial,highelectromechanicalcoupling0263-2241/$-seefrontmatterCrownCopyrightC2112010PublishedbyElsevierLtd.Allrightsreserved.Correspondingauthor.Address:SchoolofMechanicalEngineering,DalianUniversityofTechnology,No.2,LinggongRoad,GanjingziDistrict,Dalian,LiaoningProvince116024,PRChina.Tel.:+8613940925372；fax:+8641184708812.E-mailaddress:huifangl163.com(H.-F.Liu).Measurement44(2011)8895ContentslistsavailableatScienceDirectMeasuremenjournalhomepage:www.elsevierdoi:10.1016/j.measurement.2010.09.031ofsensorsinsystemdesign.Sensoristhefirstlinkformea-suringandautomaticcontrol1.Theforcesensorisoneofthewidelyusedsensors.Inrecentyears,thereisanewtypeofforcesensorwhichismagnetostrictiveforcesensor.Comparedwiththeothertypesofforcesensors,ithasobviousadvantages,suchastheefficientcouplingbetweentheelasticandmagneticstates,withstandingheavyload,shortresponsetime,lowpowerconsumption,bettercapa-bilitytoadapttoharshworkingenvironment,etc.2.Thus,magnetostrictiveforcesensoranditsrelevantas-wasusedasthesensitivematerial.Adetectioncoilpro-ducedaninducedcurrentduetothemagneticfieldtomea-sureappliedforce3.BaudendistelandTurnerstudiedaringmagnetostrictiveforcesensor1.However,themag-netostrictivecoefficientofthesematerialsusedinthesesensorsweresmall(10C0610C05)andthesensitivitywerepoor.Inaddition,thesesensorswereallbasedonthefara-daylawofelectromagneticinductionandcanonlymea-suredynamicforce.Therefore,amagnetostrictiveforcesensorwithhighsensitivitythatcanbeusedforstaticforce1.IntroductionThewisewordsofanoldengineer,sureit,youcantcontrolit”demonstratbasedonthecoupledlinearmagnetomechanicalconstitutiveequationsandtheexperi-mentalresultshowsthatthemodelisgoodatreflectingtheforce.Theoptimalbiasmag-neticfieldandsensitivityarestudiedthroughexperiments.Thesensorsensitivityis6.14timeshigherthanthatofthesensorwhichdosenothaveastainlesssteelring.Thepaperlaysafoundationforthedevelopmentofmagnetostrictiveforcesensorwithgiantmagne-tostrictivematerial.CrownCopyrightC2112010PublishedbyElsevierLtd.Allrightsreserved.youcantmea-theimportancemonlyusedinmagnetostrictiveforcesensoraresiliconsteelsheet,permalloy,electricalpureironandothersoftmagneticmaterials.KleinkeandUrasdevelopedacontact-ingmagnetostrictiveforcesensorinwhichSAE1018steelAvailableonline21September2010fluxdensityvariationunderforce.AspecialstructuresurroundingHallsensorisproposedtoimprovethesensitivity.ThedesignmethodofthegiantmagnetostrictiveforcesensorisAnovelmagnetostrictivestaticforcemagnetostrictivematerialZhen-YuanJia,Hui-FangLiu,Fu-JiWang,WeiKeyLaboratoryforPrecisionandNon-traditionalMachiningTechnologyofMinistryarticleinfoArticlehistory:Received27April2010Receivedinrevisedform6September2010Accepted14September2010abstractInordertorealizestaticforcesensor,anovelrialrodispresented.basedonthegiantChun-YaGeofEducation,DalianUniversityofTechnology,Dalian116024,PRChinaforcemeasuringandimprovethesensitivityofmagnetostrictivestaticforcesensorwithgiantmagnetostrictivemate-sensorintegratedinthesensorisusedtomeasuremagnetict.com/locate/measurementhighsensitivegiantmagnetostrictivestaticforcesensorcircuitisnecessary.DuetoitsquitelowpermeabilityofZ.-Y.Jiaetal./Measurement44(2011)889589whichusesGMMrodasthesensitiveelement.Aspecialstructurewasproposedtoimprovethesensorsensitivity.First,themeasureprincipleanddesignmethodwereex-pounded.Afterwards,FEMsoftwarewasusedtoanalyzemagneticfluxdensityofthesensor.Third,amodelwasestablishedbasedonthecoupledlinearmagnetomechani-calconstitutiveequationsandmagnetostrictionmodelanditwasverifiedbyexperiment.Inaddition,thesensorper-formanceunderdifferentbiasmagneticfiled,linearityandsensitivitywereanalyzedthroughexperiment.2.PrincipleofoperationTheoperationprincipleofthemagnetostrictiveforcesensorisbasedontheinversemagnetostrictiveeffect.In-versemagnetostrictiveeffectalsoknownastheVillarieffectspecifiesthatunderaconstantmagneticfield,themagneticpermeabilityofGMMchangeswhenitissub-jectedtoanexternalforce7.Theessenceofinversemag-netostrictiveeffectisthatunderstress,magneticdomainsinGMMrotate.Thiscausesthechangeofmagnetizationormagneticfluxdensity.Ontheonehand,magneticfieldaroundGMMrodmakesmagneticdomainsrotatetowardsthedirectionparalleltothemagneticfield.Ontheotherhand,stressmakesmagneticdomainsrotatetowardsthedirectionparticulartotheappliedstress.ThechangingprocessisshowninFig.1.Underexternalstress,magneticdomainrotatingleadstothechangeofrelativemagneticpermeabilityofGMMrodlr.ForpositiveGMM(involvedinthepaper),accordingtothetheoryofferromagnetics,iftheeternalstressiscom-pressivestress,relativemagneticpermeabilityinthestressorientationisdecreasing.Conversely,ifitistensilestress,relativemagneticpermeabilityisincreasing.Thecalcula-tionformulaofmagneticfluxdensityis:coefficient,fastresponsespeedetc.,GMMattractswideattentioninhomeandabroadacademiccircles,andindus-trialcommunity.Atpresent,forthestudyofGMM,itmainlyfocusesontheactuatorswhicharebasedonthemagnetostrictiveeffectathomeandabroadanditisrela-tivelymature.ForexampleZhejiangUniversityresearchedonmagnetostrictivematerialhigh-speedpowerfulsolenoidvalveandactuator.TheUnitedStatesETRAMAdevelopedamagnetostrictivemicro-actuator4.GMMhavebeenusedpracticallyinthefieldsofraildieselinjectionsystem,vibra-tionabsorberofturbopropaircraft,micro-feeddevice,etc.5.However,fewinvestigationshavebeendoneonmagne-tostrictiveforcesensorwhichusesGMMasthesensitiveelement.Itlacksofthenecessarydesigntheoryanditlimitsthedevelopmentofthisdevice6.Yangetal.developedagiantmagnetostrictiveforcesensorandestablisheditsmagneto-mechanicalstronglycoupledmodel2.However,agaussmeterwasusedinthesensortomeasurethemag-neticfluxdensityvariationintheairgap.Themeasuringaccuracywasrelativelylowandthemeasuringpositionwashardtocontrol.Thus,thedesignmethodandrelatedtheoryofgiantmagnetostrictivestaticforcesensorwithhighersensitivityandprecisionareneeded.Inordertofillthevacancy,thispaperproposedanovellr=5approximately,GMMrodisnotsuitableasfluxguid-ingelementintheconstructionofthesensor.Therefore,thesurroundingstructureshavetoensureguidingandfocusingofthemagneticfield.TheupperandlowerendplatesandorientationplatesmadeofhighlypermeableelectricalpureironDT4aredesignedtoworkasthefluxguidanceelements.Theprimarypurposeofthemountingcoverandoutersleeveistomakethesensormechanismassembleto-gether.Theyaremachinedwithinternalandexternalthreadrespectivelyandconnectedtogetherthroughthread.Theotherfunctionispreventingthemagneticcir-cuitfrominterferingwithexternalenvironment.Thus,antimagneticstainlesssteel1Cr18Ni9Tiisselected.Thediskspringisapreloaddevice.Itprovidesamechanicalpre-tighteningforcetothewholeinternalstructuretopre-ventitfromloosening.Thepre-tighteningforcecanbead-justedwiththethreadfitdistancebetweenmountingcoverandoutersleeve.TheexertingcompressivestressB¼l0lrHð1Þwherel0isthepermeabilityofvacuumandHisthemag-neticfieldintensity.Accordingtotheformula,thechangeoftherelativemagneticpermeabilitycausesmagneticfluxdensitychange.Sincebothl0andHareconstant,magneticfluxdensityinGMMrodchangeswithchangingexternalstress.TheconversionprocessisshowninFig.2.Thus,forcecanbemeasuredbymeasuringmagneticfluxdensity.AccordingtothechangingprocessofmagneticdomaininFig.1,theinversemagnetostrictiveeffectisrelatedtobothmagneticfieldandstress.Therefore,inordertoimprovethesensorssensitivitytheGMMrodmustbepre-magnetizationwithabiasmagneticfield.Inaddition,inor-dertomeasureforceandmakethemagneticfluxdensitybethesinglevaluedfunctionofthestress,themagneticfieldintensitymustbekeptconstant.ThebiasmagneticfieldcanbeappliedviaaconstantDCcurrentthroughexci-tationsolenoidorwithpermanentmagnet.3.DesignofthesensorAdetailedcross-sectionalviewofthemagnetostrictiveforcesensorpresentedinthepaperisshowninFig.3.Thesensormainlyconsistsofonemountingcover,oneoutersleeve,twoendplates,onecorewithwirecoils,GMMrod,onepreloaddeviceandexertingcompressivestressmechanism.Thesensorismodularindesignsothateachcomponentcanbefabricatedseparately.ThesensitiveelementGMMrodismadeofTbDyFe,anditslengthanddiameterare44mmand12mm,respec-tively.Inthesensor,GMMrodmustbeinamagneticfieldtobeinpremagnetizationstatetoimprovethesensitivity.DCexcitationcoilmodeisselectedinthesensortosupplybiasmagneticfield,whichenablesbiasmagneticfieldtobeadjustedconveniently.Thecoreisdesignedasindividualspool”tofacilitatethecoilwindingprocess.Thecoreshoulderskeepthewireinplaceafteritiswoundandfunc-tionsasloadbearingsurfacewhenthesensorisassembledandpreloaded.SinceGMMrodiscostly,itshouldbefullyutilized.Consequently,acarefuldesignofthefluxguiding90Z.-Y.Jiaetal./Measurement44(2011)8895mechanismismadeofstainlesssteel1Cr18Ni9Ti.Astheforceisappliedtoexertingcompressivestressmechanism,itistransferredtoGMMrodinaxisorientationsimultaneously.AspecialfeatureinthedesignofthemagnetostrictiveforcesensorisanintegratedlinearHallsensorallowingustomeasurethevariationofmagneticfluxdensitywithrespecttotheexternalforce.HallsensorisplacedatthebottomofGMMrodandmeasuresamagneticfluxdensityproportionaltothemagneticfluxdensityinGMMrod.InFig.1.ChangingprocessofFig.2.ChangingprocessofFig.3.Structurediagramofthemagnetostrictiveordertoimprovethesensitivityofgiantmagnetostrictiveforcesensor,whichisenhancingtheproportionalcoeffi-cientbetweenthemagneticfluxmeasuredbyHallsensorandtheactualmagneticfluxdensityinGMMrod,aspecialstructurearoundHallsensorisproposedinthepaper.ItissurroundingtheHallsensorwithastainlesssteelring.ThestructureisshownastheamplifyingpartinFig.3.Thestructureresultsfromthefollowingprinciple:themag-neticfluxlikeanelectriccurrenttakesthewaywiththeleastresistance.IfthestructurearoundtheHallsensormagneticdomains.magneticfluxdensity.forcesensor.weremadeofthefluxguidingmaterial,themagneticresis-tanceinthispathwouldhavebeenlowerthanapathcrossingHallsensor.Therefore,themagneticresistancearoundthesensorhastobechangedinsuchawaythatthereisnopathforthefluxhavingalowerresistance.Therelativemagneticpermeabilityofthestainlesssteelringisneartoone,soitmagneticallybehaveslikethesen-sorandthesurroundingair.Thus,magneticfluxcanpassHallsensor,stainlesssteelringandairaveragely.Therefore,accordingtoinversemagnetostrictivemech-anismandGMMsproperties,amagnetostrictiveforcesen-sorbasedonGMMcomprisesof:amagneticcircuithavingmagneticallyconductiveendstructuresconnectedbymag-neticallyconductivemembers,atleastoneofthemagneticmembersbeingGMMwhichisthesensitiveelementformagnetostrictiveforcesensor；meansforgeneratingasityinGMMrodishomogeneous,andmagneticfluxpassesHallsensor,stainlesssteelringandthesurroundingairZ.-Y.Jiaetal./Measurement44(2011)889591averagely.TheproportionalcoefficientbetweenmagneticfluxdensitymeasuredbyHallsensorandtheactualinGMMrodis2.Thus,themagneticfluxdensityofGMMrodcanbecalculatedbythemagneticfluxdensitymea-suredbyHallsensorwiththeproportionalcoefficient.AccordingtoHalleffectofHallsensorandtheproportionalcoefficient,magneticfluxdensityinGMMrodis:Fig.4.Analysisresultofmagneticfluxdensity.magneticfieldinmagneticcircuittomakeGMMbeinpre-magnetizationstate,aDCexcitationcoilbeingadoptedinthispapertoprovidethemagneticfield；meansforsensingthechangeofmagnetizationstate,aHallsensorbeingusedasthesensingdeviceheretomeasurethevariationofmag-neticfluxdensity；anddeviceforapplyingpre-tighteningforce.4.FEManalysisformagneticfluxdensityInthispaper,FEMsoftware(ANSYS)isusedtoanalyzethemagneticfieldcharacteristicoftheforcesensor.AtwodimensionalaxisymmetricgeometricmodelofthesensorisestablishedintheANSYS.Theairfarfieldelementisusedtosimulatefarfielddissipation.AccordingtoMax-wellequations,magneticfieldintensity,magneticfluxandmagneticfluxdensityareanalyzedandcalculated.Amongthem,thecalculatedresultofmagneticfluxdensityisshowninFig.4.Theresultsshowthat:Magneticfluxden-Brod¼2BHall¼2UC0U0K:ð2ÞInwhichBrodandBHallaremagneticfluxdensityofGMMrodandHallsensorrespectively,Uistheoutputvolt-ageofHallsensor,U0isthequiescentvoltage,Kisthesen-sitivityofHallsensor.AspecifictypeofA1302madebyAllegroMicrosystemsInc.isselectedinthispaperanditssensitivityKis1.3mv/G.Thus,themagneticsignalistrans-formedtovoltagesignalbyHallsensorandthemagneto-strictiveforcesensoroutputsignalusedinthepaperisthevoltageU.5.ModelofthesensorEqs.(3)and(4)arethemagnetostrictiveconstitutiveequationsbasedonGMMworkingattheconstanttemper-ature4.e¼sHrþdtH:ð3ÞB¼drþlrH:ð4ÞInwhicheisstrain,risstress,sHiscompliantcoeffi-cientwithconstantappliedmagneticfieldintensity,dtðde=dHjrÞismagnetostrictiveconstant,dtðdB=drjHÞispiezomagneticcoefficient,lrismagneticpermeabilitywithaconstantstress,andBismagneticfluxdensitywith-intheGMMrodsubjectedtomagneticfieldandforce.Althoughtheabovevariablesaretensorquantities,fortheforcesensorwhichisunderaxialforceandaxialmag-neticfieldonlytheaxialdirectionwillbeconsidered.Twoimportantassumptionsarebuiltintothismodel.First,lin-earoperationofthesensorisassumed.Althoughthemag-netostrictiveeffectisnonlinear,forlowsignalwhichislessthanapproximatelyone-thirdthemaximumstraincapa-bility,thelinearequationsofmagnetostrictionprovideagoodapproximation.Second,themagnetostrictionprocessisassumedtobereversible,thatis:d¼dBdrjH¼dedHjr¼dt:ð5ÞInwhichHisheldconstantforthefirstderivativeandrisheldconstantforthesecond.ThesetwoassumptionsleadtoasimplificationofEqs.(3)and(4),sinced=dt.SolvingEq.(3)forHandsubstitutingitandEq.(5)intoEq.(4)yields:B¼rdC0lrsHdC18C19þlrde:ð6Þe¼DLL:ð7ÞInwhich,DListhelengthvariationofGMMrod,Listheinitiallength.Thispaperproposesusingthemagnetostric-tionmodel8whichisbasedonthemagnetizationtocal-culatelengthvariation.DLC25LEl0B20:ð8ÞInwhichEisyoungmodulus,B0ismagneticfluxdensityoftherodonlysubjectedtoamagneticfield.B0canbecal-culatedby: