2023年全國(guó)碩士研究生考試考研英語(yǔ)一試題真題（含答案詳解+作文范文）_第1頁(yè)
已閱讀1頁(yè)，還剩8頁(yè)未讀， 繼續(xù)免費(fèi)閱讀

下載本文檔

版權(quán)說(shuō)明：本文檔由用戶提供并上傳，收益歸屬內(nèi)容提供方，若內(nèi)容存在侵權(quán)，請(qǐng)進(jìn)行舉報(bào)或認(rèn)領(lǐng)

文檔簡(jiǎn)介

1、Designation:E1962?14StardPracticefUltrasonicSurfaceTestingUsingElectromagicAcousticTransducer(EMAT)Techniques1ThisstardisissuedunderthefixeddesignationE1962thenumberimmediatelyfollowingthedesignationindicatestheyearofigi

2、naladoptioninthecaseofrevisiontheyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thispracticecoversguidelinesfutiliz

3、ingEMATtechniquesfdetectingmaterialdiscontinuitiesthatareprimarilyopentothesurface(fexamplecracksseamslapscoldshutslaminationsthroughleakslackoffusion).Thistechniquecanalsobesensitivetoflawsdiscontinuitiesthatarenotsurfa

4、cebreakingprovidedtheirproximitytothesurfaceislessthanequaltotheRayleighwavelength.1.2Thispracticecoversproceduresfthenoncontactcouplingofsurfacewavesintoamaterialviaelectromagicfields.1.3Theproceduresofthispracticeareap

5、plicabletoanymaterialinwhichacousticwavescanbeintroducedelectromagically.Thisincludesanymaterialthatiseitherelectricallyconductiveferromagicboth.1.4Thispracticeisintendedtoprovideexaminationcapabilitiesfinprocessfinalmai

6、ntenanceapplications.1.5Thispracticedoesnotprovidestardsftheevaluationofderivedindications.Interpretationclassificationultimateevaluationofindicationsalbeitnecessaryarebeyondthescopeofthispractice.Separatespecificationsa

7、greementwillbenecessarytodefinethetypesizelocationdirectionofindicationsconsideredacceptablenonacceptable.1.6Thevaluesstatedininchpoundunitsaretoberegardedasthestards.TheSIunitsgiveninparenthesesarefinfmationonly.1.7This

8、starddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatylimitationspritouse.2.Refer

9、encedDocuments2.1ASTMStards:2E543SpecificationfAgenciesPerfmingNondestructiveTestingE587PracticefUltrasonicAngleBeamContactTestingE1316TerminologyfNondestructiveExaminationsE1774GuidefElectromagicAcousticTransducers(EMAT

10、s)E1816PracticefUltrasonicTestingUsingElectromagicAcousticTransducer(EMAT)Techniques2.2ANSIASNTStards:RecommendedPracticeSNTTC1APersonnelQualificationCertificationinNondestructiveTesting3ANSIASNTCP189StardfQualificationC

11、ertificationofNondestructiveTestingPersonnel32.3MilitaryStard:MILSTD410NondestructiveTestingPersonnelQualificationCertification43.Terminology3.1Definitions:3.1.1AdditionalrelatedterminologyisdefinedinTerminologyE1316.3.2

12、DefinitionsofTermsSpecifictoThisStard:3.2.1electromagicacoustictransducer(EMAT)—anelectromagicdevicefconvertingelectricalenergyintoacousticalenergyinthepresenceofamagicfield.3.2.2Lentzfces—appliedtoelectriccurrentswhenpl

13、acedinamagicfield.Lentzfcesareperpendiculartoboththedirectionofthemagicfieldthecurrentdirection.3.2.3magostrictivefces—fcesarisingfrommagicdomainwallmovementswithinamagicmaterialduring1Thispracticeisunderthejurisdictiono

14、fASTMCommitteeE07onNondestructiveTestingisthedirectresponsibilityofSubcommitteeE07.06onUltrasonicMethod.CurrenteditionapprovedOct.12014.PublishedOctober2014.iginallyapprovedin1998.Lastpreviouseditionapprovedin2009asE1962

15、09.DOI:10.1520E196214.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.3AvailablefromAmericanNatio

16、nalStardsInstitute(ANSI)25W.43rdSt.4thFloNewYkNY10036:www.ansi.g.4AvailablefromU.S.GovernmentPrintingOfficeSuperintendentofDocuments732N.CapitolSt.NWMailStop:SDEWashingtonDC20401.ASummaryofChangessectionappearsattheendof

17、thisstardCopyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates15.4ThepurposeofthispracticeistopromotetheEMATtechniqueoftheultrasonicmethodasaviablealternativetoconventionalPTMPTmeth

18、odsfdetectingthepresenceofsurfacenearsurfacematerialdiscontinuities.5.5TheuseofEMATstheionofappropriateoperatingparameterspresupposeaknowledgeofthegeometryofthecomponenttheprobablelocationsizeientationreflectivityoftheex

19、pectedflawstheallowablerangeofEMATliftoffthelawsofphysicsgoverningthepropagationofultrasonicwaves.ThisprocedurepertainstoaspecificEMATsurfaceinspectionapplication.6.BasisofApplication6.1Thefollowingitemsaresubjecttocontr

20、actualagreementbetweenthepartiesusingreferencingthestard:6.1.1PersonnelQualification6.1.1.1Ifspecifiedinthecontractualagreementpersonnelperfmingexaminationtothispracticeshallbequalifiedinaccdancewithanationallyinternatio

21、nallyrecognizedNDTpersonnelqualificationpracticestardsuchasANSIASNTCP189SNTTC1AMILSTD410asimilardocumentcertifiedbytheemployercertifyingagencyasapplicable.Thepracticestarduseditsapplicablerevisionshallbeidentifiedintheco

22、ntractualagreementbetweentheusingparties.6.1.2QualificationofNondestructiveAgencies—IfspecifiedinthecontractualagreementNDTagenciesshallbequalifiedevaluatedasdescribedinPracticeE543.TheapplicableeditionofPracticeE543shal

23、lbespecifiedinthecontractualagreement.6.1.3ProceduresTechniques—Theprocedurestechniquestobeutilizedshallbeasspecifiedinthecontractualagreement.6.1.4SurfacePreparation—Thepreexaminationsurfacepreparationcriteriashallbeina

24、ccdancewith10.2.2unlessotherwisespecified.6.1.5TimingExtentofExamination—Shallbespecifiedinthecontractualagreement6.1.6ReptingCriteriaAcceptanceCriteria—ReptingcriteriaftheexaminationresultsshallbeinaccdancewithSection12

25、unlessotherwisespecified.Acceptancecriteriashallbespecifiedinthecontractualagreement.6.1.7ReexaminationofRepairedReWkedItems—Reexaminationofrepairedrewkeditemsisnotaddressedinthispracticeifrequiredshallbespecifiedintheco

26、ntractualagreement.7.Techniques7.1ThispracticedescribesthreeseparatetechniquesfEMATsurfacewaveexamination.Thefirstinvolvespulseechopitchcatchtechniquesfthedetectionofreflectedsurfacewaves.Thesecondtechniqueinvolvesapitch

27、catchmethodsensitivetotheattenuationofsurfacewaves.Thethirdtechniqueinvolvessurfacewavediffractionwithfocusedmeercoils.7.2PulseEchoPitchCatchReflectedSurfaceWaveTechnique—Thesetechniquesareanalogoustoconventionalultrason

28、ictechniques.Thetechniquesuseeitherone(pulseecho)two(pitchcatch)EMATsenssrelyuponthereceptionofreflectedsurfacewavesfromtheflaw.Theadvantageofthesetechniquesissimplicity.Onedisadvantageisthedifficultyindetectingallflawie

29、ntationswithoutelabatescanningroutines.Alsowhenthesetechniquesareusedfweldapplicationsaproblemarisesinthattherootcrownoftheweldcanproducereflectionsthatareprominentenoughtointerferewithevenobscureflawsignals.Whensuchinte

30、rferencesareapparentitisrecommendedthatoneoftheothertwotechniquesdescribedhereinbeutilizedtoavoidtheseproblems.7.3PitchCatchAttenuationTechnique—Theattenuationtechniqueismosteffectivelyappliedusingthearrangementofsenssil

31、lustratedinFig.3.ThetechniqueindicatesthepresenceofaflawbynotingattenuationoftheUTsignal.Thesenssusesmallpermanentmagstogeneratenarrowsurfacewavebeamsthatcrossatrightangles.ThepreferredtechniquerequirestwochannelsofEMATi

32、nstrumentationalthoughitmaybemodifiedfonechanneloperation.Toimplementonechanneloperationthedistancebetweenonetransmitterreceiverpairisincreasedslightlytodisplacethetworeceivedsignalsintime.Thetransmittercoilsarethenwired

33、inseriesthereceivercoilsarewiredinseries.ThisarrangementallowsbothpairsofEMATcoilstobeusedwithonechannelofEMATinstrumentation.Oneadvantagetotheattenuationtechniqueissensitivitytoallflawientations.Anotheradvantagetousingt

34、heattenuationtechniqueistheabilitytoscanbothsidesofaweldsimultaneously.Italsoscanslargeareasofthematerialinonescan.Adisadvantagerelatestothebeamwidthwhichmustbenarrowfocusedindertoachieveaminimumof6dBofattenuation.7.4Dif

35、fractionTechnique—ThebasisofthediffractiontechniqueisillustratedinFig.4.TwocollinearfocusedEMATs(transmitterreceiver)onepulseechoEMATarepositionedatanangle(thediffractionangle)withrespecttothenmaltotheweldcenterline.Thew

36、eldrootcrownactasaspecularreflectwhosesignalsarereflectedawayfromtheEMATreceiver.Theflawishoweverdetectedoverawideangularrangebymeansofdiffraction.Dependinguponthesizeoftheflawrelativetotheultrasonicwavelengthitactsaseit

溫馨提示

  • 1. 本站所有資源如無(wú)特殊說(shuō)明，都需要本地電腦安裝OFFICE2007和PDF閱讀器。圖紙軟件為CAD,CAXA,PROE,UG,SolidWorks等.壓縮文件請(qǐng)下載最新的WinRAR軟件解壓。
  • 2. 本站的文檔不包含任何第三方提供的附件圖紙等，如果需要附件，請(qǐng)聯(lián)系上傳者。文件的所有權(quán)益歸上傳用戶所有。
  • 3. 本站RAR壓縮包中若帶圖紙，網(wǎng)頁(yè)內(nèi)容里面會(huì)有圖紙預(yù)覽，若沒有圖紙預(yù)覽就沒有圖紙。
  • 4. 未經(jīng)權(quán)益所有人同意不得將文件中的內(nèi)容挪作商業(yè)或盈利用途。
  • 5. 眾賞文庫(kù)僅提供信息存儲(chǔ)空間，僅對(duì)用戶上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理，對(duì)用戶上傳分享的文檔內(nèi)容本身不做任何修改或編輯，并不能對(duì)任何下載內(nèi)容負(fù)責(zé)。
  • 6. 下載文件中如有侵權(quán)或不適當(dāng)內(nèi)容，請(qǐng)與我們聯(lián)系，我們立即糾正。
  • 7. 本站不保證下載資源的準(zhǔn)確性、安全性和完整性, 同時(shí)也不承擔(dān)用戶因使用這些下載資源對(duì)自己和他人造成任何形式的傷害或損失。

評(píng)論

0/150

提交評(píng)論