無損檢測技術(shù)

NondestructiveTesting大連交通大學(xué)機(jī)械工程學(xué)院

丁彥闖dyc2004@126.com課程基本情況課程面向：高等學(xué)校無損檢測、測控技術(shù)、應(yīng)用物理、材料加工、機(jī)械制造等相關(guān)專業(yè)本科學(xué)生學(xué)時：授課48學(xué)時學(xué)分：3學(xué)分學(xué)生先修課程：高等數(shù)學(xué)、大學(xué)物理、大學(xué)化學(xué)、金屬材料及金屬加工工藝基礎(chǔ)、電工與電子技術(shù)、微機(jī)原理及應(yīng)用課程內(nèi)容無損檢測緒論X射線檢測超聲波檢測磁粉檢測滲透檢測無損檢測新技術(shù)

習(xí)題課

實(shí)驗(yàn)內(nèi)容如下教學(xué)目的與要求掌握X射線照相法檢測原理、方法、設(shè)備及應(yīng)用掌握超聲波檢測原理、方法、設(shè)備及應(yīng)用掌握磁粉檢測原理、方法、設(shè)備及應(yīng)用掌握滲透檢測原理、方法、設(shè)備及應(yīng)用了解無損檢測新技術(shù)及發(fā)展考核評定方式閉卷考試（填空、簡答、選擇、計(jì)算題、設(shè)計(jì)分析等題型），考試成績占總評成績80%。平時出勤、作業(yè)、實(shí)驗(yàn)成績占總評成績20%。教材及參考資料教材楊寶清等.無損檢測技術(shù)（講義）.大連交通大學(xué)測控教研室參考資料：劉貴民主編.無損檢測技術(shù).北京：國防工業(yè)出版社，2006.1中國機(jī)械工程學(xué)會無損檢測分會編.無損檢測Ⅱ級培訓(xùn)教材射線檢測（第3版）.北京：機(jī)械工業(yè)出版社，2004.2中國機(jī)械工程學(xué)會無損檢測分會編.無損檢測Ⅱ級培訓(xùn)教材超聲波檢測（第2版）.北京：機(jī)械工業(yè)出版社，2004.2中國機(jī)械工程學(xué)會無損檢測分會編.無損檢測Ⅱ級培訓(xùn)教材磁粉檢測（第2版）.北京：機(jī)械工業(yè)出版社，2004.2李喜夢主編.無損檢測.北京：機(jī)械工業(yè)出版社，2001.2

IntroductiontoNondestructiveTesting

無損檢測簡介大連交通大學(xué)機(jī)械學(xué)院丁彥闖E-mail:dyc2004@126.comOutline（提綱）什么是無損檢測？(IntroductiontoNDT)重要性及意義

無損檢測的方法典型應(yīng)用(SelectedApplications)無損檢測的特點(diǎn)國內(nèi)外發(fā)展?fàn)顩r無損檢測技術(shù)面臨的問題前提：不損害被檢對象的使用性能方法：物理原理、化學(xué)現(xiàn)象對象：各種工程材料、零部件、結(jié)構(gòu)目的：評價完整性、連續(xù)性、安全可靠性及某些物理性能。i.e.Inspectormeasurewithoutdoingharm.（NondestructiveTesting——NDT）什么是無損檢測？“隔皮猜瓜”—無損“切開看瓜”—有損重要性共性技術(shù)（產(chǎn)品質(zhì)量、設(shè)備安全）

WTO（市場競爭、質(zhì)量競爭）

質(zhì)量保證的重要手段

制造過程的缺陷排除達(dá)不到100％

運(yùn)行中產(chǎn)生缺陷

意義

保證材料、構(gòu)件的質(zhì)量性能（依據(jù)）質(zhì)量控制、改進(jìn)工藝、節(jié)約原材料（手段，監(jiān)測）預(yù)報預(yù)測＋斷裂力學(xué)＋計(jì)算技術(shù)（經(jīng)濟(jì)效益）無損檢測的重要性及意義前蘇聯(lián)政府把資金撥給了9個無損檢測中心，直接支持了工業(yè)產(chǎn)品，特別是國防工業(yè)和航空航天領(lǐng)域的發(fā)展。無損檢測技術(shù)反映著一個國家的工業(yè)水平里根曾說，“沒有無損檢測技術(shù)，美國就不能享有眾多領(lǐng)域的領(lǐng)先地位?！?/p>

美國，有近10個無損檢測中心，100多所大學(xué)設(shè)置無損檢測的課程日本認(rèn)為，“現(xiàn)代工業(yè)是建立在無損檢測基礎(chǔ)之上的”德國在無損檢測與評價技術(shù)方面比較先進(jìn)。

第一、第二汽車制造廠僅對連桿進(jìn)行無損檢測一項(xiàng)，賠償費(fèi)用比不采用前下降了99.7%。統(tǒng)計(jì)資料顯示：經(jīng)過無損檢測后的產(chǎn)品的增值，機(jī)構(gòu)產(chǎn)品為5%，國防、宇航、原子能產(chǎn)品為12%-18%，火箭為25%左右。德國奔馳公司汽車幾千個零件經(jīng)過無損檢測后，整車運(yùn)行公里數(shù)提高了一倍。

以我國的鍋爐和壓力容器為例，據(jù)不完全統(tǒng)計(jì)，近十年間發(fā)生爆炸事故2254起，停爐停產(chǎn)重大事故20000起，造成直接經(jīng)濟(jì)損失4～5億元，間接經(jīng)濟(jì)損失80～100億元，因事故而喪生約1200人，受傷約4900人。經(jīng)濟(jì)和社會效益顯著無損檢測的方法（MethodsofNDT）VisualLiquidPenetrantMagneticParticleEddyCurrentUltrasonicX-rayMicrowaveAcousticEmissionThermographyLaserInterferometryReplicationFluxLeakageAcousticMicroscopyMagneticMeasurementsTapTesting射線（X、γ

、高能射線、中子、質(zhì)子、電子）聲和超聲（聲振、聲阻、聲發(fā)射、超聲脈沖發(fā)射、超聲成象、超聲頻譜、電磁超聲等）電學(xué)、電磁學(xué)（電阻、電位、渦輪、錄磁、漏磁、核磁共振、微波等）力學(xué)、光學(xué)（目視、內(nèi)窺、熒光、著色、光彈性覆膜、激光全息等）熱力學(xué)（熱電勢、液晶、紅外等）化學(xué)分析（電解、俄歇電子分析、穆斯鮑爾譜等）無損檢測的方法航空航天、武器核工業(yè)、電站造船、鐵路石油化工、鍋爐壓力容器建筑冶金、機(jī)械制造等典型應(yīng)用WhatareSomeUses

ofNDEMethods?FlawDetectionandEvaluationLeakDetectionLocationDeterminationDimensionalMeasurementsStructureandMicrostructureCharacterizationEstimationofMechanicalandPhysicalPropertiesStress(Strain)andDynamicResponseMeasurementsMaterialSortingandChemicalCompositionDeterminationFluorescentpenetrantindicationWhenareNDEMethodsUsed?ToassistinproductdevelopmentToscreenorsortincomingmaterialsTomonitor,improveorcontrolmanufacturingprocessesToverifyproperprocessingsuchasheattreatingToverifyproperassemblyToinspectforin-servicedamageThereareNDEapplicationatalmostanystageintheproductionorlifecycleofacomponent.FiveMostCommonNDTMethodsLiquidPenetrant

MagneticUltrasonicEddyCurrentX-rayAliquidwithhighsurfacewettingcharacteristicsisappliedtothesurfaceofthepartandallowedtimetoseepintosurfacebreakingdefects.Theexcessliquidisremovedfromthesurfaceofthepart.Adeveloper(powder)isappliedtopullthetrappedpenetrantoutthedefectandspreaditonthesurfacewhereitcanbeseen.Visualinspectionisthefinalstepintheprocess.ThepenetrantusedisoftenloadedwithafluorescentdyeandtheinspectionisdoneunderUVlighttoincreasetestsensitivity.LiquidPenetrantInspectionMagneticParticleInspectionThepartismagnetized.Finelymilledironparticlescoatedwithadyepigmentarethenappliedtothespecimen.Theseparticlesareattractedtomagneticfluxleakagefieldsandwillclustertoformanindicationdirectlyoverthediscontinuity.Thisindicationcanbevisuallydetectedunderproperlightingconditions.

MagneticParticleCrackIndications

RadiographyTheradiationusedinradiographytestingisahigherenergy(shorterwavelength)versionoftheelectromagneticwavesthatwe

seeasvisiblelight.TheradiationcancomefromanX-raygeneratororaradioactivesource.HighElectricalPotentialElectrons-+X-rayGeneratororRadioactiveSourceCreatesRadiationExposureRecordingDeviceRadiationPenetratetheSampleConductive

materialCoilCoil'smagneticfieldEddycurrentsEddycurrent'smagneticfieldEddyCurrentTestingEddyCurrentTestingEddycurrenttestingisparticularlywellsuitedfordetectingsurfacecracksbutcanalsobeusedtomakeelectricalconductivityandcoatingthicknessmeasurements.

Hereasmallsurfaceprobeisscannedoverthepartsurfaceinanattempttodetectacrack.UltrasonicImagingGrayscaleimageproducedusingthesoundreflectedfromthefrontsurfaceofthecoinGrayscaleimageproducedusingthesoundreflectedfromthebacksurfaceofthecoin(inspectedfrom“heads”side)Highresolutionimagescanbeproducedbyplottingsignalstrengthortime-of-flightusingacomputer-controlledscanningsystem.CommonApplicationofNDTInspectionofRawProductsInspectionFollowingSecondaryProcessingIn-ServicesDamageInspectionInspectionofRawProductsForgings,Castings,Extrusions,etc.MachiningWeldingGrindingHeattreatingPlatingetc.InspectionFollowing

SecondaryProcessingCrackingCorrosionErosion/WearHeatDamageetc.InspectionFor

In-ServiceDamagePowerPlantInspectionProbeSignalsproducedbyvariousamountsofcorrosionthinning.Periodically,powerplantsareshutdownforinspection.Inspectorsfeededdycurrentprobesintoheatexchangertubestocheckforcorrosiondamage.PipewithdamageWireRopeInspectionElectromagneticdevicesandvisualinspectionsareusedtofindbrokenwiresandotherdamagetothewireropethatisusedinchairlifts,cranesandotherliftingdevices.StorageTankInspectionRoboticcrawlersuseultrasoundtoinspectthewallsoflargeabovegroundtanksforsignsofthinningduetocorrosion.Camerasonlongarticulatingarmsareusedtoinspectundergroundstoragetanksfordamage.AircraftInspectionNondestructivetestingisusedextensivelyduringthemanufacturingofaircraft.NDTisalsousedtofindcracksandcorrosiondamageduringoperationoftheaircraft.Afatiguecrackthatstartedatthesiteofalightningstrikeisshownbelow.JetEngineInspectionAircraftenginesareoverhauledafterbeinginserviceforaperiodoftime.Theyarecompletelydisassembled,cleaned,inspectedandthenreassembled.Fluorescentpenetrantinspectionisusedtocheckmanyofthepartsforcracking.SiouxCity,Iowa,July19,1989AdefectthatwentundetectedinanenginediskwasresponsibleforthecrashofUnitedFlight232.CrashofUnitedFlight232PressureVesselInspectionThefailureofapressurevesselcanresultintherapidreleaseofalargeamountofenergy.Toprotectagainstthisdangerousevent,thetanksareinspectedusingradiographyandultrasonictesting.RailInspectionSpecialcarsareusedtoinspectthousandsofmilesofrailtofindcracksthatcouldleadtoaderailment.BridgeInspectionTheUShas578,000highwaybridges.Corrosion,crackingandotherdamagecanallaffectabridge’sperformance.ThecollapseoftheSilverBridgein1967resultedinlossof47lives.Bridgesgetavisualinspectionaboutevery2years.Somebridgesarefittedwithacousticemissionsensorsthat“l(fā)isten”forsoundsofcracksgrowing.NDTisusedtoinspectpipelinestopreventleaksthatcoulddamagetheenvironment.Visualinspection,radiographyandelectromagnetictestingaresomeoftheNDTmethodsused.

Remotevisualinspectionusingaroboticcrawler.

Radiographyofweldjoints.

Magneticfluxleakageinspection.Thisdevice,known