【astm標(biāo)準(zhǔn)】e 1000 - 98 (2009)

1、Designation:E1000?98(Reapproved2009)StardGuidefRadioscopy1ThisstardisissuedunderthefixeddesignationE1000thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecaseofrevisiontheyearoflastrevision.

2、Anumberinparenthesesindicatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.1.Scope1.1Thisguideisftutialpurposesonlytooutlinethegeneralprinciplesofradioscopicimaging.1.2This

3、guidedescribespracticesimagequalitymeasuringsystemsfrealtimenearrealtimenonfilmdetectiondisplayrecdingofradioscopicimages.Theseimagesusedinmaterialsexaminationaregeneratedbyperatingradiationpassingthroughthesubjectmateri

4、alproducinganimageonthedetectingmedium.AlthoughthedescribedradiationsourcesarespecificallyXraygammaraythegeneralconceptscanbeusedfotherradiationsourcessuchasneutrons.Theimagedetectiondisplaytechniquesarenonfilmbuttheuseo

5、fphotographicfilmasameansfpermanentrecdingoftheimageisnotprecluded.NOTE1—FinfmationpurposesrefertoTerminologyE1316.1.3Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoft

6、heuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatylimitationspritouse.FspecificsafetyprecautionarystatementsseeSection6.2.ReferencedDocuments2.1ASTMStards:2E142MethodfControll

7、ingQualityofRadiographicTesting(Withdrawn2000)3E747PracticefDesignManufactureMaterialGroupingClassificationofWireImageQualityIndicats(IQI)UsedfRadiologyE1025PracticefDesignManufactureMaterialGroupingClassificationofHoleT

8、ypeImageQualityIndicats(IQI)UsedfRadiologyE1316TerminologyfNondestructiveExaminationsE2002PracticefDeterminingTotalImageUnsharpnessinRadiology2.2NationalCouncilonRadiationProtectionMeasurement(NCRP)Stards:NCRP49Structura

9、lShieldingDesignEvaluationfMedicalUseofXRaysGammaRaysofEnergiesupto10MeV4NCRP51RadiationProtectionDesignGuidelinesf0.1–100MeVParticleAcceleratFacilities4NCRP91(supercedesNCRP39)RecommendationsonLimitsfExposuretoIonizingR

10、adiation42.3FederalStard:Fed.Std.No.21CFR1020.40SafetyRequirementsfCabiXRayMachines53.SummaryofGuide3.1Thisguideoutlinesthepracticesftheuseofradioscopicmethodstechniquesfmaterialsexaminations.Itisintendedtoprovideabasicu

11、nderstingofthemethodthetechniquesinvolved.Theionofanimagingdeviceradiationsourceradiologicalopticaltechniquestoachieveaspecifiedqualityinradioscopicimagesisdescribed.4.SignificanceUse4.1Radioscopyisaversatilenondestructi

12、vemeansfexamininganobject.Itprovidesimmediateinfmationregardingthenaturesizelocationdistributionofimperfectionsbothinternalexternal.Italsoprovidesarapidcheckofthedimensionsmechanicalconfigurationthepresencepositioningofc

13、omponentsinamechanism.Itindicatesinrealtimethepresenceofstructuralcomponentimperfectionsanywhereinamechanismanassembly.Throughmanipulationitmayprovidethreedimensionalinfmationregardingthenaturesizesrelativepositioningofi

14、temsofinterestwithinanobjectcanbefurtheremployedtocheckthefunctioningofinternalmechanisms.Radioscopypermitstimelyassessmentsofproductintegrity1ThisguideisunderthejurisdictionofASTMCommitteeE07onNondestructiveTestingisthe

15、directresponsibilityofSubcommitteeE07.01onRadiology(XGamma)Method.CurrenteditionapprovedJune12009.PublishedJuly2009.iginallyapprovedin1989.Lastpreviouseditionapprovedin2003asE100098(2003).DOI:10.1520E100098R09.2Freferenc

16、edASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMwebsite.3Thelastapprovedversionofthishisticalstardisreferencedonwww

17、.astm.g.4AvailablefromNCRPPublications7010WoodmontAve.Suite1016BethesdaMD20814.5AvailablefromStardizationDocumentsderDeskBldg.4SectionD700RobbinsAve.PhiladelphiaPA191115094Attn:NPODS.Copyright?ASTMInternational100BarrHar

18、bDrivePOBoxC700WestConshohockenPA194282959.UnitedStates1ofthatfconventionalradiography.Thecostsofexpendablesmanpowerproducthlingtimehoweverareusuallysignificantlylowerfradioscopicsystems.6.SafetyPrecautions6.1Thesafetypr

19、oceduresfthehlinguseofionizingradiationsourcesmustbefollowed.MatyrulesregulationsarepublishedbygovernmentallicensingagenciesguidelinesfcontrolofradiationareavailableinpublicationssuchastheFed.Std.No.21CFR1020.40.Carefulr

20、adiationsurveysshouldbemadeinaccdancewithregulationscodesshouldbeconductedintheexaminationareaaswellasadjacentareasunderallpossibleoperatingconditions.7.InterpretationReferenceStards7.1ReferenceradiographsproducedbyASTMa

21、cceptancestardswrittenbyotherganizationsmaybeemployedfradioscopicexaminationaswellasfradiographyprovidedappropriateadjustmentsaremadetoaccommodatefthedifferencesinthefluoscopicimages.8.RadioscopicDevicesClassification8.1

22、ThemostcommonlyusedelectromagicradiationinradioscopyisproducedbyXraysources.Xraysareaffectedinvariousmodesdegreesbypassagethroughmatter.Thisprovidesveryusefulinfmationaboutthematterthathasbeentraversed.Thedetectionofthes

23、eXrayphotonsinsuchawaythattheinfmationtheycarrycanbeusedimmediatelyistheprimerequisiteofradioscopy.SincetherearemanywaysofdetectingthepresenceofXraystheirenergyfluxdensitythereareanumberofpossiblesystems.Oftheseonlyafewd

24、eservemethantheattentioncausedbyscientificcuriosity.Fourpurposeshereonlythesefewareclassifieddescribed.8.2BasicClassificationofRadioscopicSystems—AllcommonlyusedsystemsdependontwobasicprocessesfdetectingXrayphotons:Xrayt

25、olightconversionXraytoelectronconversion.8.3XRaytoLightConversion–RadioscopicSystems—InthesesystemsXrayphotonsareconvertedintovisiblelightphotonswhicharethenusedinvariouswaystoproduceimages.Theprocessesarefluescencescint

26、illation.CertainmaterialshavethepropertyofemittingvisiblelightwhenexcitedbyXrayphotons.Thoseusedmostcommonlyareasfollows:8.3.1Phosphs—Theseincludethecommonlyusedfluorescentscreenscomposedofrelativelythinunifmlayersofphos

27、phcrystalsspreaduponasuitablesuppt.Zinccadmiumsulfidegadoliniumoxysulfidelanthanumoxybroecalciumtungstateareincommonuse.Coatingweightsvaryfromapproximately50mgcm2to100mgcm.28.3.2Scintillats—Thesearematerialswhicharetrans

28、parentemitvisiblelightwhenexcitedbyXrays.Theemissionoccursveryrapidlyfeachphotoncaptureeventconsistsofapulseoflightwhosebrightnessisproptionaltotheenergyofthephoton.Sincethematerialsaretransparenttheylendthemselvestoopti

29、calconfigurationsnotpossiblewiththephosphsusedindinaryfluescentscreens.Typicalmaterialsusedaresodiumiodide(thalliumactivated)cesiumiodide(thalliumactivated)sodiumiodide(cesiumactivated).Thesesinglecrystalmaterialscanbeob

30、tainedinverylargesizes(upto30cm12in.diameterisnotuncommon)canbemachinedintovarioussizesshapesasrequired.Thicknessof2to100mm(0.08to4in.)arecustomary.8.4XRaytoElectronConversion—RadioscopicSystems—Xrayphotonsofsufficienten

31、ergyhavetheabilitytoreleaselooselyboundelectronsfromtheinnershellsofatomswithwhichtheycollide.ThesephotoelectronshaveenergiesproptionaltotheiginalXrayphotoncanbeutilizedinavarietyofwaystoproduceimagesincludingthefollowin

32、gusefulprocesses.8.4.1EnergizingofSemiconductJunctions—Theresistanceofasemiconductofasemiconductjunctioninadevicesuchasadiodetransistcanbealteredbyaddingfreeelectrons.TheenergyofanXrayphotoniscapableoffreeingelectronsins

33、uchmaterialscanprofoundlyaffecttheoperationofthedevice.Fexampleasimplesilicon“solarcell”connectedtoamicroammeterwillproduceasubstantialcurrentwhenexposedtoanXraysource.8.4.1.1Ifanarrayofsmallsemiconductdevicesisexposedto

34、anXraybeamtheperfmanceofeachdeviceissampledthenanimagecanbeproducedbyasuitabledisplayofthedata.Sucharrayscanbelineartwodimensional.Lineararraysnmallyrequirerelativemotionbetweentheobjectthearraytoproduceausefulrealtimeim

35、age.Thechoicedependsupontheapplication.8.4.2AffectingResistanceofSemiconducts—ThemostcommonexampleofthisistheXraysensitivevidiconcameratube.Herethetargetlayerofthevidicontubeitssupptaremodifiedtohaveanimprovedsensitivity

36、toXrayphotons.TheresultisachangeinconductivityofthetargetlayercrespondingtothepatternofXrayfluxfallinguponthetubethisisdirectlytransfmedbythescanningbeamintoavideosignalwhichcanbeusedinavarietyofways.8.4.2.1Photoconducti

37、vematerialsthatexhibitXraysensitivityincludecadmiumsulfidecadmiumselenideleadoxideselenium.ThelattertwohavebeenusedinXraysensitiveTVcameratubes.CadmiumsulfideiscommonlyusedasanXraydetectbutnotusuallyfimagefmation.8.4.3Mi

38、crochannelPlates—TheseconsistofanarraybundleofverytinyshttubeseachofwhichunderproperconditionscanemitalargenumberofelectronsfromoneendwhenanXrayphotonstrikestheotherend.ThenumberofelectronsemitteddependsupontheXrayfluxpe

39、runitareathusanelectronimagecanbeproduced.Thesedevicesmustoperateinavacuumsothatapracticalimagingdeviceispossibleonlywithcarefulpackaging.Usuallythiswillmeanthatacombinationofprocessesisrequiredasdescribedmecompletelyin8

40、.5.8.5CombinationsofDetectingProcesses—RadioscopicSystems—Avarietyofpracticalsystemscanbeproducedbyvariouscombinationsofthebasicmechanismsdescribedtogetherwithotherdevicesftransfmingpatternsoflightelectronsresistancechan