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3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(hù)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:B244?09(Reapproved2014)EndsedbyAmericanElectroplaters’SocietyEndsedbyNationalAssociationofMetalFinishersStardTestMethodfMeasurementofThicknessofAnodicCoatingsonAluminumofOtherNonconductiveCoatingsonNonmagicBa

2、sisMetalswithEddyCurrentInstruments1ThisstardisissuedunderthefixeddesignationB244thenumberimmediatelyfollowingthedesignationindicatestheyearofiginaladoptioninthecaseofrevisiontheyearoflastrevision.Anumberinparenthesesind

3、icatestheyearoflastreapproval.Asuperepsilon()indicatesaneditialchangesincethelastrevisionreapproval.ThisstardhasbeenapprovedfusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thistestmethodcoverstheuseofeddycurrentinst

4、rumentsfthenondestructivemeasurementofthethicknessofanonconductivecoatingonanonmagicbasismetal.Itisintendedtosupplementmanufacturers’instructionsftheoperationoftheinstrumentsisnotintendedtoreplacethem.1.2Thistestmethodis

5、particularlyusefulfmeasuringthethicknessofananodiccoatingonaluminumalloys.Chemicalconversioncoatingsaretoothintobemeasuredbythistestmethod.1.3ThevaluesstatedinSIunitsaretoberegardedasthestard.Thevaluesgiveninparenthesesa

6、refinfmationonly.1.4Thisstarddoesnotpurpttoaddressallofthesafetyconcernsifanyassociatedwithitsuse.Itistheresponsibilityoftheuserofthisstardtoestablishappropriatesafetyhealthpracticesdeterminetheapplicabilityofregulatylim

7、itationspritouse.2.ReferencedDocuments2.1ASTMStards:2B499TestMethodfMeasurementofCoatingThicknessesbytheMagicMethod:NonmagicCoatingsonMagicBasisMetals3.Terminology3.1DefinitionsofTermsSpecifictoThisStard:3.1.1accuracyn—t

8、hemeasureofthemagnitudeoferrbetweentheresultofameasurementthetruethicknessoftheitembeingmeasured.3.1.2adjustmentn—thephysicalactofaligningainstrument’sthicknessreadingstomatchthoseofaknownthicknesssample(removalofbias)in

9、dertoimprovetheaccuracyoftheinstrumentonaspecificsurfacewithinaspecificptionofitsmeasurementrange.Anadjustmentwillaffecttheoutcomeofsubsequentreadings.3.1.3calibrationn—thehighlevelcontrolleddocumentedprocessofobtainingm

10、easurementsontraceablecalibrationstardsoverthefulloperatingrangeoftheinstrumentthenmakingthenecessaryinstrumentadjustments(asrequired)tocrectanyoutoftoleranceconditions.3.1.3.1Discussion—Calibrationofcoatingthicknessinst

11、rumentsisperfmedbytheequipmentmanufactureranauthorizedagentbyanauthizedtrainedcalibrationlabatyinacontrolledenvironmentusingadocumentedprocess.Theoutcomeofthecalibrationprocessistoresterealigntheinstrumenttomeetexceedthe

12、manufacturer’sstatedaccuracy.3.1.4referencestardn—aspecimenofknownthicknessusedtoverifytheaccuracyofacoatingthicknessmeasuringinstrument.3.1.5verificationofaccuracyn—obtainingmeasurementsonareferencestardpritoinstrumentu

13、sefthepurposeofdeterminingtheabilityofthecoatingthicknessinstrumenttoproducereliablevaluescomparedtothecombinedinstrumentmanufacturer’sstatedaccuracythestatedaccuracyofthereferencestard.4.SummaryofTestMethod4.1Instrument

14、scomplyingwiththistestmethodmeasurecoatingthicknessbytheuseofeddycurrents.Aprobeisplaceddirectlyonthecoatedsurfaceinaperpendicularpositionelectroniccircuitryisusedtoconvertareferencesignalintoacoatingthicknessmeasurement

15、.1ThistestmethodisunderthejurisdictionofASTMCommitteeB08onMetallicInganicCoatingsisthedirectresponsibilityofSubcommitteeB08.10onTestMethods.CurrenteditionapprovedMay12014.PublishedMay2014.iginallyapprovedin1949.Lastprevi

16、ouseditionapprovedin2009asB244–09.DOI:10.1520B024409R14.2FreferencedASTMstardsvisittheASTMwebsitewww.astm.gcontactASTMCustomerServiceat.FAnnualBookofASTMStardsvolumeinfmationrefertothestard’sDocumentSummarypageontheASTMw

17、ebsite.Copyright?ASTMInternational100BarrHarbDrivePOBoxC700WestConshohockenPA194282959.UnitedStates18.5Curvature—Measurementsareaffectedbythecurvatureofthetestspecimen.Theinfluenceofcurvaturevariesconsiderablywiththemake

18、typeofinstrumentbutalwaysbecomesmepronouncedastheradiusofcurvaturedecreases.8.6SurfaceRoughness:8.6.11Measurementsareinfluencedbythesurfacetopographyofthesubstratethecoatingaroughsurfacewillgiveindividualinstrumentreadin

19、gsthatwillvaryfrompointtopoint.Inthiscaseitisnecessarytomakemanyreadingsatdifferentpositionstoobtainanaveragevaluethatisrepresentativeofthemeancoatingthickness.Ifthebasismetalisroughitmayalsobenecessarytocheckadjustifnec

20、essarythezerooftheinstrumentatseveralpositionsonasampleoftheuncoatedroughsubstrate.Iftheroughnessofthesubstratesurfaceissmallrelativetothecoatingthicknessitseffectwillprobablybenegligible.8.6.2Ifthebasismetalisroughitmay

21、alsobenecessarytocheckadjustifnecessarythezerooftheinstrumentatseveralpositionsonasampleoftheuncoatedroughsubstrate.Iftheroughnessofthesubstratesurfaceissmallrelativetothecoatingthicknessitseffectwillprobablybenegligible

22、.8.7FeignParticles—Theprobesofeddycurrentinstrumentsmustmakephysicalcontactwiththetestsurfacearetherefesensitivetofeignmaterialthatpreventsintimatecontactbetweentheprobethecoatingsurface.Boththetestsurfaceinstrumentprobe

23、shouldbekeptfreeoffeignmaterial.8.8Pressure—Thepressurewithwhichtheprobeisappliedtothetestspecimenaffectstheinstrumentreadingsshouldtherefebekeptconstant.8.9NumberofReadings—Theprecisionofthemeasurementscanbeimprovedbyin

24、creasingthenumberofreadingsinaccdancewithstatisticalprinciples.9.Procedure9.1Operateeachinstrumentinaccdancewiththeinstructionsofthemanufacturer.GiveappropriateattentiontothefactslistedinSection8.9.2Verifytheaccuracyofth

25、einstrumentatthetestsiteeachtimetheinstrumentisputintoserviceatfrequentintervalsduringusetoassureproperperfmance.9.3Manyinstrumentscanbeadjustedindertoimprovetheiraccuracyonaspecificsurfacewithinaspecificptionofitsmeasur

26、ementrange.Theeffectsofpropertiesofthesubstrate(compositionshaperoughnessedgeeffectselectricalproperties)coating(compositionmasssurfaceroughness)aswellasambientsurfacetemperaturesmayrequireadjustmentstobemadetotheinstrum

27、ent.Followthemanufacturer’sinstructions.9.4Observethefollowingprecautions:9.4.1BasisMetalThickness—Checkwhetherthebasismetalthicknessexceedsthecriticalthickness.Ifnoteitherusethebackupmethodin7.5makesurethatthecalibratio

28、nadjustmenthasbeenmadeonareferencestardhavingthesamethicknesselectricalpropertiesasthetestspecimen.9.4.2EdgeEffects—Donotmakereadingsclosetoanedgeholeinsidecneretc.ofaspecimenunlessthevalidityofthecalibrationadjustmentfs

29、uchameasurementhasbeendemonstrated.9.4.3Curvature—Donotmakereadingsonacurvedsurfaceofaspecimenunlessthevalidityofthecalibrationadjustmentfsuchameasurementhasbeendemonstrated.9.4.4NumberofReadings—Becauseofnmalinstrumentv

30、ariabilityitisnecessarytomakeseveralreadingsateachposition.Localvariationsincoatingthicknessmayalsorequirethatanumberofmeasurementsbemadeinanygivenareathisappliesparticularlytoaroughsurface(see8.9).9.4.5SurfaceCleanlines

31、s—Befemakingmeasurementscleananyfeignmattersuchasdirtgreasecrosionproductsfromthesurfacewithoutremovinganycoatingmaterial.10.Accuracy10.1Theinstrumentitscalibrationitsoperationshallbesuchthatthecoatingthicknesscanbedeter

32、minedwithin10%1mwhicheverisgreaterofthetruethickness.11.Rept11.1Thereptshallincludethefollowinginfmation:11.1.1Typeofinstrumentusedincludingmanufacturermodelnumberprincipleofoperationdateofcalibration11.1.2Sizedeionoftes

33、tspecimen11.1.3Whetherspecialjigswereused11.1.4Typeofcoatingthicknessstardreferencestardthemethodusedfaccuracyverificationanycalibrationadjustment11.1.5Thenumberofmeasurementstakenthevalueofeachmeasurement11.1.6Operatide

34、ntification11.1.7Date.NOTE1—Althoughtheeticallythistestmethodcanbeusedfmeasuringnonconductivecoatingsonamagicbasismetalitsusefcoatingsbelow25m(1mil)isnotrecommendedthemagicmethodoutlinedinTestMethodB499shallbeused.12.Pre

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(hù)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(méi)有圖紙預(yù)覽就沒(méi)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(hù)上傳內(nèi)容的表現(xiàn)方式做保護(hù)處理，對(duì)用戶(hù)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(hù)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