1、BRITISH STANDARD BS EN 13925-1:2003 Non-destructive testing X-ray diffraction from polycrystalline and amorphous materials Part 1: General principles The European Standard EN 13925-1:2003 has the status of a British Standard ICS 19.100 BS EN 13925-1:2003 This British Standard was published under the
2、 authority of the Standards Policy and Strategy Committee on 20 March 2003 BSI 20 March 2003 ISBN 0 580 41463 9 National foreword This British Standard is the official English language version of EN 13925-1:2003. The UK participation in its preparation was entrusted to Technical Committee WEE/46, No
3、n-destructive testing, which has the responsibility to: A list of organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BS
4、I Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for
5、its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK inter
6、ests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages 2 to 13 and a back cover. The BSI copyright date displayed in this document indicates when the
7、 document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NORMEEUROPENNE EUROPISCHENORM EN139251 March2003 ICS19.100 Englishversion NondestructivetestingXraydiffractionfrompolycrystalline andamorphousmaterialPart1:Generalprinciples EssaisnondestructifsDiff
8、ractiondesrayonsXapplique auxmatriauxpolycristallinsetamorphesPartie1: Principesgnraux ZerstrungsfreiePrfungRntgendiffraktometrievon polykristallinenundamorphenMaterialienTeil1: AllgemeineGrundlagen ThisEuropeanStandardwasapprovedbyCENon14November2002. CENmembersareboundtocomplywiththeCEN/CENELECInt
9、ernalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteration.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheManagementCentreortoanyCENmember. ThisEuropeanStandardexistsinthreeoffic
10、ialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoitsownlanguageandnotifiedtotheManagementCentrehasthesamestatusasthe official versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,CzechRepublic,Denmark,Finland,France,G
11、ermany,Greece, Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal,Slovakia,Spain,Sweden,SwitzerlandandUn ited Kingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2003CEN Allrightso
12、fexploitationinanyformandbyanymeansreserved worldwideforCENnationalMembers. Ref.No.EN139251:2003EEN139251:2003(E) 2 Contents page Foreword3 Introduction .4 1 Scope 5 2 Normativereferences 5 3 Termsanddefinitions. .5 4 GeneralprinciplesofXraypowderdiffraction(XRPD) . 6 5 Meaningoftheword“powder”inter
13、msofXraydiffraction 7 6 Characteristicsofpowderdiffractionlineprofiles. 7 7 Typesofanalysis . 8 7.1 General8 7.2 Phaseidentification(alsoreferredtoas“Qualitativephaseanalysis”) 8 7.3 Quantitativephaseanalysis. .8 7.4 Estimationofthecrystallineandamorphousfractions . .9 7.5 Determinationoflatticepara
14、meters . .9 7.6 Determinationofcrystalstructures . 9 7.7 Refinementofcrystalstructures 9 7.8 Characterisationofcrystallographictexture 9 7.9 Macrostressdetermination. 10 7.10 Analysisofcrystallitesizeandmicrostrain. .10 7.10.1 General10 7.10.2 Determinationofcrystallitesize(sizeofcoherentlyscatterin
15、gdomains) 11 7.10.3 Determinationofmicrostrains 11 7.11 Electronradialdistributionfunction(RDF) .11 8 Specialexperimentalconditions. .11 AnnexA (informative) RelationshipsbetweentheXRPDstandards .12 Bibliography 13EN139251:2003(E) 3 Foreword Thisdocument(EN139251:2003)hasbeenpreparedbyTechnicalCommi
16、tteeCEN/TC138“Nondestructive testing“,thesecretariatofwhichisheldbyAFNOR. ThisEuropeanStandardshallbegiventhestatusofanationalstandard,eitherbypublicationofanidenticaltextor byendorsement,atthelatestbySeptember2003,andconflictingnationalstandardsshallbewithdrawnatthe latestbySeptember2003. ThisEurop
17、eanStandardabout“NondestructivetestingXraydiffractionfrompolycrystallineandamorphous material” iscomposedof: EN139251 Part1:GeneralPrinciples; EN139252 Part2:Procedures; prEN139253 Part3:Instruments; prEN139254 Part4:ReferenceMaterials. Inordertoexplaintherelationshipbetweenthetopicsdescribedinthedi
18、fferentStandards,adiagramillustrating typicaloperationinvolvedinXRPDisgiveninannexA. AnnexAisinformative. AccordingtotheCEN/CENELECInternalRegulations,thenationalstandardsorganizationsofthefollowing countriesareboundtoimplementthisEuropeanStandard:Austria,Belgium,CzechRepublic,Denmark,Finland, Franc
19、e,Germany,Greece,Hungary,Iceland,Ireland,Italy,Luxembourg,Malta,Netherlands,Norway,Portugal, Slovakia,Spain,Sweden,SwitzerlandandtheUnitedKingdom.EN139251:2003(E) 4 Introduction Xraypowderdiffraction(XRPD)isapowerfulNonDestructiveTesting(NDT)methodfordeterminingarangeof physicalandchemicalcharacteri
20、sticsofmaterials.Theseincludethetypeandquantitiesofphasespresent,the crystallographicunitcellandstructure,crystallographictexture,macrostress,crystallitesizeandmicrostrain,and theelectronradialdistributionfunction. ThisstandardaimstodescribethegeneralaspectsoftheXRPDtechniqueanditsapplicationsbutnot
21、todefinea specificordetailedstandardforeachfieldofapplicationortypeofanalysis. Themainpurposesofthestandardaretherefore: toprovidepracticalguidance,unifiedconceptsandterminologyforuseoftheXRPDtechniqueintheareaofNon DestructiveTestingwithgeneralinformationaboutitscapabilitiesandlimitationsofrelevanc
22、etolaboratories workingatdifferentlevelsofsophistication,fromroutinetestingtoresearch; toprovideabasisforqualityassuranceinXRPDlaboratoriesallowingperformancetestingandmonitoringof instrumentsandthecomparisonofresultsfromdifferentinstruments; toprovideageneralbasis(withoutimposingspecifications)forf
23、urtherspecificNDTproductstandardsandrelated QualityAssuranceapplications,withaspectscommontomostfieldsofapplication. Inordertomakethestandardimmediatelyusableinawiderangeoflaboratoriesandapplications,diffractometers withBraggBrentanogeometryareconsideredinmostdetail. RadiationProtection .Exposureofa
24、nypartofthehumanbodytoXrayscanbeinjurioustohealth.Itistherefore essentialthatwheneverXrayequipmentisused,adequateprecautionsshouldbetakentoprotecttheoperator andanyotherpersoninthevicinity.Recommendedpracticeforradiationprotectionaswellaslimitsforthelevels ofXradiationexposurearethoseestablishedbyna
25、tionallegislationineachcountry.Iftherearenoofficial regulationsorrecommendationsinacountry,thelatestrecommendationsoftheInternationalCommissionon RadiologicalProtectionshouldbeapplied.EN139251:2003(E) 5 1Scope ThisEuropeanStandardspecifiesthegeneralprinciplesofXraydiffractionfrompolycrystallineandam
26、orphous materials.Thismaterialstestingmethodhastraditionallybeenreferredtoas“XrayPowderDiffraction(XRPD)”, andisnowappliedtopowders,bulkmaterials,thinfilm,andothers.Asthemethodcanbeusedforvarioustypesof materialsandtoobtainalargevarietyofinformation,thisstandardreviewsalargenumberoftypesofanalysisbu
27、t remainsnonexhaustive. 2 Normativereferences ThisEuropeanStandardincorporatesbydatedorundatedreference,provisionsfromotherpublications.These normativereferencesarecitedattheappropriateplacesinthetext,andthepublicationsarelistedhereafter.For datedreferences,subsequentamendmentstoorrevisionsofanyofth
28、esepublicationsapplytothisEuropean Standardonlywhenincorporatedinitbyamendmentorrevision.Forundatedreferencesthelatesteditionofthe publicationreferredtoapplies(includingamendments). EN139252:2003, NondestructivetestingXraydiffractionfrompolycrystallineandamorphousmaterialPart2: Procedures. 3 Termsan
29、ddefinitions ForthepurposesofthisEuropeanStandard,thegeneraltermsanddefinitionsconcerningXraypowder diffraction 1) andthefollowingapply. 3.1 powder largenumberofcrystallitesand/orparticles(i.e.grains,agglomeratesoraggregates;crystallineornoncrystalline) irrespectiveofanyadhesionbetweenthem 3.2 block
30、 selfadheringsinglepieceofinterconnectedparticlesorcrystallites 3.3 specimen portionofthesampleinthespecificformusedinthediffractioninstrumentforagivendatacollectionprocess 3.4 phase portionofaphysicalsystemsharingacommonmolecularandintermolecularstructureirrespectiveofany subdivisionbysizedistribut
31、ionorshape NOTE Thetermphaseisusedasashortformforacrystallographicphaseorathermodynamicphasethroughoutthis standard,unlessexplicitlystatedotherwise. 3.5 diffractionline regionofthediffractionpatterncontaininganintensitymaximumandcorrespondingtodiffractionfromasetof latticeplanes NOTE Ofteninterchang
32、eablyreferredtoasapeak,reflectionorBraggreflection. 1) adraftofEuropeanStandard(WI00138078“NondestructivetestingTerminologyXraypowderdiffraction“)isin preparation.EN139251:2003(E) 6 4 GeneralprinciplesofXraypowderdiffraction(XRPD) XraydiffractionresultsfromtheinteractionbetweenXraysandelectronsofato
33、ms.Usually,i.e.inthesocalled kinematicdescriptionofdiffraction,atomsareconceivedaspointscatterers.Dependingontheatomic arrangement,interferencesresultbetweenthescatteredrays.Interferencesareconstructivewhenthepath differencebetweentwodiffractedraysdifferbyanintegralnumberofwavelengths.Thisselectivec
34、onditionis describedbytheBraggequation,alsocalledBraggslaw: 2d hkl sinq hkl = nl (1) where hkl isasetoflatticeplanesidentifiedbytheMillerindicesh,k,l, d hkl isthedistancebetweensuccessivecrystallatticeplanes(alsocalledthe“dspacing“) l isthewavelengthoftheXraysusedandisoftheorderofmagnitudeofthedspac
35、ing. q hkl istheangle betweentheincidentbeamandthehkllatticeplanesandhalfofthesocalled“diffractionangle“, i.e.theangle betweenthedirectionsoftheincidentbeamandthediffractedbeam(seeFigure1). n isthediffractionorder(seehereafter): 1) theequation(1)(Braggequation),issatisfiedifthepathdifference(AB+BC)b
36、etweentheraysscattered fromsuccessivelatticeplanesofthesamesetisanexactmultipleof l (seeFigure1). Key d Separationbetweentwosuccessivelatticeplanes. q Anglebetweentheincidentbeamandthelatticeplanesseparatedbyadistanceofd. AandC Pointsontheincidentbeam(So)andthediffractedbeam(S). BandDrepresenttwooft
37、hepointscatterers,oneineachlatticeplane. Figure1DiffractionofXraysfromtwosuccessivelatticeplanes 2)the diffraction of n th orderfromlatticeplanehklisequivalenttoadiffractionoffirstorderfromthesetof latticeplanesnh,nk,nl.FormostpurposesinXRPD, nistakenasunityandequation(1)ismorecommonly usedintheform
38、: 2d hkl sinq hkl = l (2) wherethesymbolsareasinequation(1).EN139251:2003(E) 7 InXRPDthespecimenisideallypolycrystallinewithcrystallitesinallorientations,enablingdiffractiontobe observedaccordingtoequation(1).Thepositionsofthediffractionlinesarecharacteristicofthecrystallattice,their intensitiesdepe
39、ndonthecrystallographicunitcellcontent,andthelineprofilesontheperfectionandextentofthe crystallattice. Undertheseconditionsthediffractionlinehasafinitedistributionofintensityarisingfromatomicarrangement, thermalmotionandstructuralimperfectionsaswellasfrominstrumentcharacteristics.Thisintensitydistri
40、butionis describedastheconvolutionofafunctioncombiningthecontributionsofthevariousinstrumentcharacteristicswith afunctiondescribingtheintrinsicspecimencontributionstobroadening. Todeterminethediffractionpatternofaspecimen,twoexperimentalmethodscanbeusedalternatively: the“angulardispersivetechnique”w
41、heretheXraysaremonochromaticandthemeasurementismadeby scanningthediffractionangle, the“energydispersivetechnique“wheretheXraysarepolychromaticandtheenergyorwavelengthoftheX raysphotonsismeasuredatafixeddiffractionangle. AseriesofreferencesofgeneralvaluestoXraydiffractionandCrystallographyareusedinth
42、isstandard(see Bibliography1,2,3,4,5,6,7). 5 Meaningoftheword“powder”intermsofXraydiffraction Theterm“powder”,asusedinXRPD,doesnotstrictlycorrespondtotheusualsenseofthewordincommon language.InXraypowderdiffractionthespecimencanbea”solidsubstancedividedintoverysmallparticles”,but itcanalsobeasolidblo
43、ckforexampleofmetal,ceramic,polymer,glassorathinfilmorevenaliquid.Thereason forthisisthattheimportantparametersfordefiningtheconceptofapowderforadiffractionexperimentarethe numberandsizeoftheindividualcrystallitesthatformthespecimenandnottheirdegreeofaccretion. Anidealpowderforadiffractionexperimentconsistsofalargenumberofsmall,randomlyorientedcrystallites (coherentlydiffractingcrystallinedomains).Ifthisnumberissufficientlylarge,therearealwaysenough
