超声波探伤英文资料

Ultrasoundisamechanicalwave,mechanicalvibrationsandfluctuationsinthephysicalbasisofultrasonictesting.

Reciprocatingcyclicmovementofanobjectalongastraightlineorcurveinanearequilibriumposition,knownasthemechanicalvibration.Propagationofvibration,knownasvolatility.Fluctuationsintomechanicalwavesandelectromagneticwavestwocategories.Mechanicalwavepropagationofmechanicalvibrationsinanelasticmedium.Theultrasoundisamechanicalwave.

Themainparametersofthemechanicalwavewavelength,frequencyandwavevelocity.:thedistancebetweenthesametwoadjacentoscillationphaseofthesamewavelineparticleknownasthewavelength,sourceormedium,anyoneparticletocompleteafullvibrationwavejustforwardawavelengthdistance,commonlyusedinmeters(m);Wavelengthfrequencyf:fluctuationsintheprocess,heservedasagivenpointinonesecond,adoptedbythenumberofcompletewaveiscalledfrequency,commonlyusedinunitsofhertz(Hz);wavevelocityC:fluctuationsinthewaveperunittimetransmittedThedistanceiscalledthewavevelocity,thecommonunitsofmeters/second(m/s).

f,wavelengthandwavevelocityisproportionaltoandinverselyproportionaltofrequency;whenthefrequencyisfixed,thewavevelocitythegreaterthewavelengththemorelong;wavevelocitywhenthefrequencylower,themorelongwavelengthAvailablebytheabovedefinition:C=.

Sub-sonic,sonicandultrasonicmechanicalwavepropagationinanelasticmedium,thepropagationvelocityinthesamemedium.Theirdifferencemainlyduetodifferentfrequencies.Frequencybetween20~20000Hzcancausepeopletohearingthemechanicalwaveiscalledsoundwavesatfrequenciesbelow20Hzmechanicalwavesknownasinfrasound,frequenciesabove20000Hzofmechanicalwavescalledultrasound.Infrasound,ultrasoundcannotbeheard.

Thefrequencyoftheultrasonicflawdetectionisgenerallybetween0.5~10MHz,theinspectionofsteelandothermetalmaterials,commonlyusedfrequencyfor1~5MHz.Ultrasonicwavelengthisveryshort,whichdeterminestheultrasoundhasanumberofimportantfeatures,sothatitcanbewidelyusedfornondestructivetesting.

Gooddirection:Ultrasoundishighfrequency,veryshortwavelengthmechanicalwave,thewavelengthusedinthenondestructivetestingofmillimeter;ultrasoundlikelightwaveshasagooddirectioncanbedirectedemission,easytobefoundinthematerialwasseizeddefects.

(2)highenergy:energy(sound)andisproportionaltothesquareoffrequency,ultrasonicenergyismuchlargerthantheenergyofordinarysoundwaves.

3intheinterfacereflection,refractionandwaveconversion:ultrasoniconsomeofthefeaturesofthegeometricalacoustics,suchasastraightlineinthemedium,thecaseofinterfacereflection,refractionandwaveconversion.

Penetratingpower:whentheultrasonicwavepropagationinmostmedia,thedisseminationofenergylossissmall,thepropagationdistance,abilitytopenetrateitsabilitytopenetrateuptoseveralmetersinsomemetallicmaterials.

Ultrasonicflawdetectoristhefrequencyabove20kHz,beyondthepeopleearstodistinguishbetweentalentedandpenetratingastrongsoundwaves.Isaportableindustrialnon-destructiveflawdetector,itcanbetoofast,convenient,nodamagetotheworkpieceinternalvarietyofdefects(welds,cracks,folding,loosesandholes,pores,adulterated,etc.),detect,locate,evaluateanddiagnostics.Bothcanbeusedtocarryouttheroom,canalsobeusedfortheprojectsite.Commonlyusedinboilers,pressurevessels,aerospace,aviation,electricpower,petroleum,chemicalindustry,offshoreoilpipeline,military,shipbuilding,automobiles,machinerymanufacturing,metallurgy,metalprocessingindustries,steelstructures,railtransport,nuclearpower,universityandotherindustries.

Ultrasonicflawdetectorreason:theuseofultrasonicreflectiontruthnondestructivedetectiononthedefectsinthedata,whentheultrasoundtoconveytheinformationtobedetected,dataacousticcharacteristicsandtheinternalorganizationoftheinevitableimpactofchangesonultrasoniccommunication,throughultrasoundbyaffectthelevelandcircumstancesofthedetectionsurveydatafeaturesandskillsofthetectonicshiftknownasultrasonictesting.

ColorultrasonicflawdetectorLEDdisplayiscolorful,multi-colorselection,orthepremiseofdivergentlight,backlightcontinuationadjustable,moreintuitiveQinmusee.

Therearemanyabouttheuseoftheultrasonicflawdetector,forexample,thereflectionofultrasoundtomeasuretheinterval,theapplicationofhigh-powerultrasonicvibrationtoeliminatethescaleattachedtotheboilerabove,theapplicationofhigh-energyultrasoundmadethe"harmonicscalpel"togetridofcrushingthehumanbodycancer,stones,etc.,theeffectandthepenetratingpoweroftheultrasonicflawdetector,thereflectionoftheapplicationofultrasoundcanbeastraightlinetoconveythecharacteristicsofthedetectionisagreatuseofareas.Ultrasonicflawdetectionusingthedetectionofprimarycovervarioustypesofinformationintheindustrialandmedicaltestinganddiagnosisonthehumanbody,afterwhichonecandetectmetalsandotherindustrialinformation,thereisnobubble,scars,cracksandotherdefectscanbedetectedCannormalpeoplethebody'ssofttissue,bloodflow.

Peopleishowthesampleapplicationofultrasoundtodetect?

Ultrasonicflawdetectoriscurrentlymortalisthemeasuredobject(forexample,industrialinformation,thehumanbody)emissionultrasound,andthenapplythereflection,Dopplereffect,transmissiontoobtaintheinformationinsidethemeasuredobjectandformimagesthroughthedisposal.Ultrasonicflawdetector,theDopplereffectmethodistheapplicationofultrasoundintheattacktoencountertheobjectofactivitiesoftheDopplershifteffecttodrawthecharacteristicsoftheactivitiesoftheobjectsbiasandspeed;transmissionruleisparsedultrasoundtopenetratethroughmeasuredobjectafterthetransformationtoderivetheinternalfeaturesofobjects,theiruseinthedevelopmentstage;ultrasonicflawdetector,thefirstintroductionsisthewaytothemostfrequentlyusedreflectionmethodtoobtainthecharacteristicinformationoftheobjectinterior.Thereflectionmethodisbasedonultrasoundtaskaftertheonsetofstrongreflectionofthedifferencesbetweentheacousticimpedanceoftissueinterfacereason,asweknow,soundwavesfromonemediumtoconveytoamediumofhoursoftheinterfacebetweenthetwowillbeattheonsetofreflection,andthegreaterthedifferencebetweenthemediareflectedthegreaterwillbe,sowecanlaunchanobjectpenetratingpower,ultrasoundcanbeastraightlinetoconveytheultrasonicflawdetectorandthereflectedultrasonicacceptedandThistissuecontainsvarioustypesofmediabigandsmallcanbedeterminedbasedonthestatusofthereflectedultrasoundhasamplitudeultrasoundhasspreadstatusandavarietyofmediacfthedifferenceinthelevelofinformation(areflectionbackreflectsthereflectiveinterfacefromthedetectionoftheappearanceoftheinterval,themagnitudemayreflectthemediabigandsmall,mutatismutandis,tothedifferencesinlevelandothercharacteristics),ultrasonicflawdetectorandthendiscriminantofthemeasuredobjectcanhaveabnormal.Theoccurrenceoftouchtoagoodmanyinthisprocess,includingultrasound,acceptedflagssignaloftrafficlightsanddisposal.Oneoftheultrasonicapproachistoencourageelectricflagslightsafterthecircuitispassedtothepiezoelectriceffectofcrystal(cristobalite,sulfuricacid,lithium,etc.),sothatthevibrationandultrasonic;buttoacceptthereflectedultrasoundaftermidnight,thispressureThetransistorwasthepressureofthereflectedsoundwaveswilloccurelectricflagslightsandsendaseriesofdisposaltothedisposalofflagslightscircuit,ultrasonicflawdetectorconstitutethefinalimageforpeopletolookatdiscrimination.

Herebasedontheimagedisposalmethods(thatistogettheflagslightsconvertedtoimagesinwhatway)thespeciescanbedividedintoA-typeshows,M-typetypeB,typeC,F-typedisplay.A-typedisplayisoneoftheultrasoundflagswillbeacceptedlightsdisposalintoawaveformimagebasedontheshapeofthewaveformcanbeseenthatthemeasuredobjectwhichcanhaveanomaliesanddeficienciesintheside,howmuch,ultrasonicflawdetectorfirstusedtoindustrialinspection;theM-typedisplayistheonethroughthedetectionofluminancedisposalaccordingtoworkonebyoneopenedconstituteaone-dimensional"spacemulti-eventtimingdiagram",suitabletolookattheinternalactiveformobjects,ultrasonicflawdetector,suchasactivitiesorgans,arteries,etc.;TypeBshowsalotthroughthedetectionofluminancedisposalgroupconsistingoftwo-dimensionalside-by-side,whichreflectstheobject'sinternalfaultsectionoftheanatomicalimages(diseasebackyarduseBsuperthisisthereasontodoit),ultrasonicflawdetectorissuitabletolookinternallyatstaticobjects;C-typeF-typedisplaywithunmatchedless.Ultrasonicflawdetectionwillnotbeveryprecise,andmoreconvenientcomparedwithotherdetectionmethods,fast,norwillitdetectobjectsandoperatorrisk,sowerethepeoplemoreandmorethroughoutthefarewell,hasaverybroadcarriedoutprospects.

Thedevelopmentofultrasoundandintheoverhaulofthestate

Abstract:Inthevarioustypesofpowerplantequipmentmaintenance,servicelifeassessment,themostfrequentandwidelyusedinultrasonictestingtechnology.Ultrasonicflawdetectionapplications,applicability,highaccuracy,easyautomationofanumberofadvantages.Thispaperfocusesonthecrackdetectionmethodforultrasonicinspectiontechnology,quantitativemethodsofdefect,damage,deteriorationevaluationmethods,andevaluation,andapplicationexamples.

Keywords:ultrasonictestingcracksdamagedeteriorationevaluationapplications

1Preface

Mostcomponentsofthepowerplantequipmentinthelong-termapplicationinhightemperatureandhighpressurewater,steam,media,stress,corrosion,creep,hydrogencorrosionandfatiguecausedbyagingdamageanddeteriorationofamoreseriousproblem.Signalacquisitioninthemaintenance,servicelifeassessmentworkonthesedevices,themostfrequentandextensiveapplicationofultrasonictechnology.Ultrasonicthintubetothethicktube,surfacetotheinternaldefectinformationcollectioniswidelyusedinevaluationofrapid,quantitativedefects,easyon-siteinspection,analytical,anddegreeofautomationofmanyoftheadvantagesofitareuniversallyapplied.

Therefore,toaccuratelycapturethesetinysignals,anditsresolution,musthavehigh-performancemeasurementsystem.Inrecentyears,highsensitivity,high-performance,highreliabilityoftheultrasonicsendingandreceivinghasbeencommercialized,alongwiththeincreaseofhigh-speed,high-capacity,signalprocessing,dataprocessingcapabilitiesofcomputers,image,imageanalysis,automationisalsoincreasinglyeasy;Inaddition,thedoublecrystalprobe,focusingtheprobesurfaceSHwaveprobe,climbingwaveprobeandtemperatureprobeandanelectromagneticultrasonicnon-contactprobessuchaswidelyused.Inthiscontext,recentanalyticinthelaboratorystage,theaccumulationofbasicdata,andwidelypromotedtheapplicationofawidevarietyofultrasoundassessmentofdamageanddeteriorationofdiagnostictechniquesinthefieldcanbeachieved.

Twoultrasonicflawinspectionmethods

Sofar,havebeenappliedorproposedapplicationofultrasonicflawdetectionnondestructiveinspectionmethodsareshowninTables:

Defectsinquantitativemethodsequivalentmethod(equivalenttestmethod,theequivalentcalculationmethod,theequivalentAVGcurvemethod)

Lengthmeasurementmethod(relativesensitivitylengthmeasuringmethod,theabsolutesensitivityofthelengthmeasurementmethod,theendpointpeakmethod)

Theendofwaveheightmethod

CrackdetectionsurfacewaveSupremeCourt

Surfacewavedelaymethod(single-probemethod,dual-probemethod)

Endoftheechopeakmethod

Shear-waveside-anglereflectionmethod

Serialtransversewavetwo-probemethod

Relativesensitivitymethod(6dB,10dB,20dB)

Scatteredwavemethod(diffraction)

Damage,deteriorationevaluationmethodofattenuation(low-levelechoreflectionmethod,transmissionmethod,theresonancemethod)

Sonicmethod(SAWmethod,thevolumemethod)

Thecriticalangleofreflection

Spectrometermethod(spectraldistributionandsizeofthecenterfrequency,frequency,amplitude,gravityfrequency)

Frequencyanalyticalmethod

Behindthescatteringwaveclutteranalysis

Other(δlaw,Poissonratioevaluationmethod)

3crackevaluationandapplicationexamples

3.1FocusedUltrasound

Widelyusedasamethodcanbeeasilymeasuredinthefieldistherelativesensitivitymeasurementmethod.Thismethodistheheightofmorethanechotheprobebeforeandafterscanningthedistance-amplitudecurve(distanceamplitudecurvetotheDAC),thebeamawayaroundthethresholdtomeasurethecrackheightofamethod.Theaccuracyofthemethoddependsonthewidthoftheultrasonicbeamtocrackahighdegreeofmeasurementaccuracycanbeincreasedthroughtheuseofultrasonicamplitudenarrowfocusprobe.

Surfaceoccurredinthepowergenerationequipment,water-walltubecorrosionfatiguecracking,stresscorrosioncrackingandpetrochemicalequipmentalkalicorrosionembrittlementcrackdefectsgeneratedbythestainlesssteelweldingpartsahighdegreeofmeasurementgenerallyusedscatteringmethod(TimeOfFlightDiffraoctionofTOFD).TheTOFDFranceBS7706specifiedinthemethod,willlaunchtheprobeandreceivingprobeplacedatacertaindistancefromtheweldonbothsidesofthelaunchprobeemitsthespreadoflongitudinalwave,thecracktipdiffractedwavemeasurementofcrackheightof.Signalinthecrackisonlyspreadinthetestsurfaceshearwaveandtheunderlyingsimplewaveformofthereflectedwave,butinthecaseofcracks,butalsoreceivedfromthecrackthetopandbottomofthediffractedwave.Soisthedemandontheinjurypatternofeachsignalarrivaltimedifferenceandthesevalues​​measurethecrackdepthandheight.Collectedreflectedsignalwaveformdataconvertedbycomputerprocessing,transformintothephaseextentwithlightanddarkgray-scaletestingresultsforreal-timeimagedisplay.Intheconventionalmethod,iftheangleofincidencedeviatesfrom10°,thesensitivitywasreducedbyapproximately25dB,TOFDmethodis5dB,relativedecrease.ItcanbesaidthattheTOFDmethodhasgoodcrackdetectionperformancelesssusceptibletotheinfluenceofthecrackslope.

Japanisstudyingtheuseofthelargeopeningangleofthelinetofocustheprobe,sothataleakinthetestsurfaceoftheelasticwave(LSAW),quantitativeevaluationofstainlesssteeltointergranularattack(IGA)ahighdegreeofmethod.ExperimentalresultsshowthattheintergranularcorrosionitselfbetweentheheightandthetheLSAWechoamplitudehaveagoodrelationship.

3.2SurfaceSHwaves

Theaverageangleprobetheshearwavevibrationdirectionintheworkpieceintheworkpiecesurfaceisperpendiculartotheplaneofvibration,saidSVwave;wavevibrationdirectionandtheworkpieceparalleltothesurface,knownastheSHwave.PiezoelectricvibrationwaveintheroleoftheinversepiezoelectriceffectbythewaveformconversionintheheterogeneousinterfaceintheSHwavewasseizedmedia.

ThetestprovedreciprocatingtransmittanceoftheSHwaveprobewithincreasingtheangleofrefractionofSH-waveprobeinsteelincreaseswithdecreasingfrequencywasincreased,thedifferencebetweenhighandlow-frequencyprobeatdifferentanglesthereciprocatingtransmittancereciprocatingtransmittanceofthefrequencyoftheprobeonadifferentangleofrefractiondifferenceissmall.Verifytheresultscomparedwiththetheoreticalresults,theconsistencyofthehigh-frequencyprobeisbetter,theconsistencyofthelow-frequencyprobesomewhatlesscertain,whichischipconsideredinthetheoreticalcalculationsfortheinfiniteplane,theactualtestchipforthefinitesize.Whenappliedtoengineeringpractice,theSHwaveprobeisdividedintoalargeangleofSHwaveangleprobeprobeandsurfaceSHwave.

SurfaceSHwavelessdemandingontheworkpiecesurfacefinish,surfaceSHwaveaneffectivetestforgreaterdistance,canimprovetheefficiencyofinspection;appliedtotheinspectionofturbinebladesleavesthebodytocompletethelaststagebladelengthofthetest,andisnotthefinalstagebladecavitation.Inspectionandverticaltreebladerootinspectionsensitivitycanreach1mm.Appliedtotheinnerwallfatiguecrackinspection,theinspectionsensitivitycanreach0.5mm.

SHwaveprobetestsensitivitybycouplingeffectgreatly.ThisdifferencewasmainlyduetotheshearwaveemittedbytheprobeSHwavesareshearwaves,canonlybespreadinthesolidmedium.Dedicatedshearwavecouplingagentatdifferenttemperatures,throughsoundeffectsquitedifferent,boththeshearwaveinthereciprocatingtransmittanceoftheinterfacearequitedifferent,resultinginagreaterchangeinthemediumwavesoundfieldintensity,resultingintestsensitivitydifferences.Therefore,practicalapplication,usuallyusedintheambienttemperatureisnotverydifferentcircumstances,iftheambienttemperaturedifferentresponsetothetestingequipment,testsensitivityisre-calibration.AngleofSHwaveangleprobebecauseofthesoundfieldintensityintherangeofabout0-10mmunderthesurfaceandthesurface,thesoundfieldintensityappliedtothethinworkpieceinspection,thedefectlocation(depthdirection)isdifficulttobeabletoaccuratelylocate.

DuetosurfaceSHwavehasalltheadvantagesdescribedabove,soexpecttobewidelyusedinnon-destructiveexaminationofthestructuralelements.Flawdetectionforthepipingofthermalpowerequipment,suchastheuseofweldedpartsoftheoccurrenceofcracks,foreigncountrieshavedevelopedafield-orientedelectronicscanningsystem,andhasalreadybeguntheapplication.Suchastheuseofarc-arrayprobe,thefan-shapedscanoftheultrasonicbeamofelectrons,thecross-sectionimageofthetestbodyreal-timedisplayofthemobileimagingsystem.

Damage,deteriorationevaluationandapplicationexamples

4.1Evaluationofcreepdamage

Thecreepdamageunderhightemperature,longtimetoloadacertainload,theintergranularcavitiesandotherphenomena.Theultrasonicevaluationmethodofitsapplicationwavevelocitymethod,theattenuationspectroscopy,frequencyresolutionandnoiseanalysis,thetheoreticalanalysisarealsodiverse.Whichclutteranalysisfromtheaccuracyandapplicabilityofthemethodismoreeffective.Theapproachisfromtherearofthemetaltostructuralchangesintissuescatteringwaveasclutterprocessingandquantitativeevaluationoftheamplitudeofamethod,andthenusingtheintegralvalueofacertainfrequencyrange.

4.2hydrogencorrosiondamageassessment

Hydrogendamageinhightemperature(>220°C)underhighpressureconditions,whentheboilerwaterPH<5,thecondenserleak,thewatersupplyofinorganicacidsorresincontamination,dirtunderthereaction3Fe+4H2O→ofFe3O4+8[H]generatedhydrogenatomscalelayertoblocktheworkingfluidcannotbetakenaway,thenwiththegrainboundarycarbidereactionofFe3C+4of[H]→3Fe+CH4↑,themethanegasgeneratedbythegrainboundarycracking,crackorbulgeformedinthetubewall,thesteelperformancedegradationofabrittlefailure.Hydrogendamagewithspeedanddestruction,damagearea,thedamagecannotberestored,noteasytothecharacteristicsofearlydetection.

High-frequencyultrasoundRFechocanbeappliedtothedetectionofhydrogendamageμm-levelmicro-cracks,withcoarsesandpapertoremovethepre-testtubetheappearanceofslagpoint,thecouplingagentonthe28throllingoil.Therefore,bydetectingthisechocanunderstandtheinternalhydrogendamagemicrocrack.Generallyconsideredthatultrasoundcanbefoundinthesmallestdefectsizeasthewavelength1/2.Inrecentyears,theoreticalstudieshaveshownthat,ifdoesnotrequireahighdegreeofecho,andwiththehigh-frequencydigitaloscilloscope,theinstrumentsensitivityandsignaltonoiseratiowillbehigh,thediscontinuitydetectionsensitivitycanreachawavelengthof1/5~1/10.Suchastheprobefrequencyis15MHzwhenusingthesinglediscontinuitycanbedetectedcanbeassmallas40μm~75μm.

4.3sensitiveevaluationofthedegreeof

Ifstainlesssteelisusedinhightemperature,duetosensitizationtogeneratechromiumdepletionregionisinducedintergranularcorrosionreasons,ultrasoundevaluationofthekeyistoconfirmthecorrelationbetweenthePoisson'sratiodeterminedbythedegreeofsensitizationandultrasoniclongitudinalandshearwaves,sensitiveevaluationofPoisson'sratioasanindexlevelofthemethodiscurrentlybeingstudied.

Sensitizationofthegraincanbeseenasthecentralpartsandthepartsofthesolutionintheintergranularelementswithdifferentconcentrationsofshell-likestructure,theuseofshell-likestructureofthescatteringbodyscatteringtheorytocalculatethefrequencydependenceofultrasonicspeedofsoundandattenuationwithTheincreaseinthefrequencyattenuationoftheincreaseinthespeedofsoundcausedbythespeedofsoundtoreducethedevelopmentoforientationandsensitizationincreasetendencyisconsistentwiththeexperimentalvalues.

4.4two-phasestainlesssteelthermalagingevaluation

Ifthetwo-phasestainlesssteelismaintainedat300~450°Cforalongtime,intheαphasesegregationdecompositioncausedbyheataging(brittle).Thespeedofsoundchangeswiththethermalaging,fromboththeoreticalandexperimentalstudieshaveshownthatthenumericalsimulationresultsandexperimentalvalues​​correspondtogood.However,thermalagingonthetwo-phasestainlesssteel,caststeel,bycastingorganizationswithcoarseparticlesanditsSHwave,thespeedofsoundandtheagingtime,a