会员注册 | 登录 | 微信快捷登录 支付宝快捷登录 QQ登录 微博登录 | 帮助中心 人人文库renrendoc.com美如初恋!
站内搜索 百度文库

热门搜索: 直缝焊接机 矿井提升机 循环球式转向器图纸 机器人手爪发展史 管道机器人dwg 动平衡试验台设计

   首页 人人文库网 > 资源分类 > DOC文档下载

外文翻译--关于北欧的疲劳实验室的比较—测量结果不确定值的反映.doc

  • 资源星级:
  • 资源大小:225.00KB   全文页数:13页
  • 资源格式: DOC        下载权限:注册会员/VIP会员
您还没有登陆,请先登录。登陆后即可下载此文档。
  合作网站登录: 微信快捷登录 支付宝快捷登录   QQ登录   微博登录
友情提示
2:本站资源不支持迅雷下载,请使用浏览器直接下载(不支持QQ浏览器)
3:本站资源下载后的文档和图纸-无水印,预览文档经过压缩,下载后原文更清晰   

外文翻译--关于北欧的疲劳实验室的比较—测量结果不确定值的反映.doc

3附录附录1英文原文Reflectionsregardinguncertaintyofmeasurement,ontheresultsofaNordicfatiguetestinterlaboratorycomparisonMagnusHolmgren,ThomasSvensson,ErlandJohnson,KlasJohanssonAbstractThispaperpresentstheexperiencesofcalculationandreportinguncertaintyofmeasurementinfatiguetesting.SixNordiclaboratoriesperformedfatiguetestsonsteelspecimens.Thelaboratoriesalsoreportedtheirresultsconcerninguncertaintyofmeasurementandhowtheycalculatedit.Theresultsshowlargedifferencesinthewaytheuncertaintiesofmeasurementwerecalculatedandreported.Nolaboratoryincludedthemostsignificantuncertaintysource,bendingstressduetomisalignmentofthetestingmachine,incorrectspecimensand/orincorrectlymountedspecimens,whencalculatingtheuncertaintyofmeasurement.SeverallaboratoriesdidnotcalculatetheuncertaintyofmeasurementinaccordancewiththeGuidetotheExpressionofUncertaintyinMeasurementGUM1.KeywordUncertaintyofmeasurement,Calculation,Report,Fatiguetest,LaboratoryintercomparisonDefinitionsRStressratioFmin/FmaxFForcenektonsAandBFatiguestrengthparameterssandSStressmegapascalsNNumberofcycles.IntroductionThecorrectorbestmethodofcalculatingandreportinguncertaintyofmeasurementintestinghasbeenthesubjectofdiscussionformanyyears.TheissuebecameevenmorerelevantinconnectionwiththeintroductionofISOstandards,e.g.ISO170252.Thediscussion,aswellasimplementationoftheuncertaintyofmeasurementconcept,hasoftenbeenconcentratedonwhichequationtouseoronadministrativehandlingoftheissue.Therehasbeenlessinterestinthetechnicalproblemandhowtohandleuncertaintyofmeasurementintheactualexperimentalsituation,andhowtolearnfromtheuncertaintyofmeasurementcalculationwhenimprovingtheexperimentaltechnique.Onereasonforthismaybethattheaccreditationbodieshaveconcentratedontheveryexistenceofuncertaintyofmeasurementcalculationsforanaccreditedtestmethod,insteadofonwhetherthecalculationsareperformedinasoundtechnicalway.Thepresentinvestigationemphasizestheneedforamoretechnicalfocus.Onetestingareawhereitisdifficulttodouncertaintyofmeasurementcalculationsisfatiguetesting.However,thereisguidanceonhowtoperformsuchcalculations,e.g.inRefs.3,4.Toinvestigatehowuncertaintyofmeasurementcalculationsareperformedforfatiguetestsinreallife,UTMIStheSwedishfatiguenetworkstartedaninterlaboratorycomparisonwhereone4ofthemostessentialpartswastocalculateandreporttheuncertaintyofmeasurementofatypicalfatiguetestthatcouldhavebeenorderedbyacustomeroftheparticipatinglaboratories.Forcostreasons,customersoftenaskforalimitednumberoftestspecimensbut,atthesametime,theyrequestalotofinformationaboutalargeportionofthepossiblestresslifeareafromfewcycleshighstressestomillionsofcycleslowstressesandevenrunouts.Thewaythecalculationwasmadeshouldalsobereported.Theoutcomeconcerningtheuncertaintyofmeasurementfromtheprojectisreportedinthisarticle.ParticipantsSixNordiclaboratoriesparticipatedintheinterlaboratorycomparisononeindustriallaboratory,tworesearchinstitutes,twouniversitylaboratoriesandonelaboratoryinaconsultancycompany.Twoofthelaboratoriesareaccreditedforfatiguetesting,andathirdlaboratoryisaccreditedforothertests.Eachparticipantwasrandomlyassignedanumberbetween1and6,andthisnotificationwillbeusedintherestofthispaper.ExperimentalprocedureTheparticipantsreceivedinformationaboutthetestspecimenswithoutmaterialdata,togetherwithinstructionsonthewaytoperformthetestandhowtoreporttheresults.Theinstructionswerethattestsshouldbeperformedasconstantloadamplitudetests,withR0.1atthreedifferentstresslevels,460,430and400Map,withfourspecimensateachstresslevel,atatestfrequencybetween10and30Hz,witharunoutlimitat6510cyclesandinanormallaboratoryclimate0203Cand5015relativehumidity.Thiswasconsideredasatypicalcustomerorderedtest.Thetestresultsweretobeusedtocalculateestimatesofthetwofatiguestrengthparameters,AandB,accordingtolinearregressionofthelogsandlongvariables,i.e.loglogABN.ThereportedresultshouldincludeboththeestimatedparametersAandBandtheuncertaintiesinthemduetomeasurementerrors.Thereportshouldalsoincludetheconsiderationsandcalculationsbehindtheresults,especiallythoseconcerninguncertaintyofmeasurement.Severalpropertiesweretobereportedforeachspecimen.Themostimportantonewasthenumberofcyclesuntilfractureorifthespecimenwasarunouti.e.survivedfor6510cycles.ThetestsweretobeperformedinaccordancewithASTME466–965andISO572526.ASTME46696doesnottakeuncertaintyofmeasurementintoaccountHowever,ASTME46696mentionsthatthebendingstressintroducedowingtomisalignmentmustnotexceed5ofthegreateroftherange,maximumorminimumstresses.Therearealsorequirementsfortheaccuracyofthedimensionalmeasurementofthetestspecimen.Allparticipantsusedhydraulictestingmachines.Thetestspecimensweremadeofsteelyieldstress375–390Map,andtensilestrength670–690Map,tabulatedvalues.Thetestspecimensweredistributedtotheparticipantsbytheorganizer.Results5TheprimarylaboratoryresultsthatshouldbecomparedaretheestimatedWhalercurves.Inordertopresentallresultsinthesameway,theorganizertransformedsomeoftheresults.TheWhalercurvesreportedbytheparticipantsareshowninFig.1.Itcanbeseenthatthereareconsiderabledifferencesbetweenlaboratories.Anapproximatestatisticaltestshowsasignificantlaboratoryeffect.MaterialscatteralonecannotexplainthedifferencesintheWhalercurves.Inordertoinvestigateifthelaboratoryeffectwassolelycausedbythemodelinguncertainty,weestimatednewparametersfromtherawdatawithacommonalgorithm.Wethenchosetouseonlythefailedspecimensandtomaketheminimizationinthelogarithmiclifedirection.TheresultsareshowninFig.2.Aformalstatisticalsignificancetestwasthenmade,andtheresultofsuchatestshowsthatthedifferencesbetweenthelaboratoriesshowninFig.1couldbeattributedonlytomodeling.UncertaintyofmeasurementcalculationsOneofthemostimportantobjectiveswiththisinvestigationwastocomparetheobserveddifferencesbetweenlaboratorytestresultswiththeirestimateduncertaintiesofmeasurement.Theintentionwastoanalyzetheuncertaintyanalysesassuch,andtocomparethemtothestandardprocedurerecommendedintheISOguideGuidetotheExpressionofUncertaintyinMeasurementGUM1.Thelaboratoriesidentifieddifferentsourcesofuncertaintyandtreatedthemindifferentways.Thesesourcesaretheloadmeasurement,theloadcontrol,thesuperimposedbendingstressesbecauseofmisalignmentandthedimensionalmeasurements.Implicitly,laboratorytemperatureandhumidity,specimentemperatureandcorrosioneffectsarealsoconsidered.Inaddition,theresultsshowamodelingeffect.ThedifferentlaboratorytreatmentsofthesesourcesaresummarizedinTable1.SpecificcommentsonthedifferentlaboratoriesAlllaboratoriesgavetheirlaboratorytemperatureandhumidity,butdidnotconsiderthesevaluesassourcesofuncertainty,i.e.theinfluenceoftemperatureandhumiditywasneglected.Thisconclusionisreasonableforsteelinthetemperaturerangeandhumidityrangeinquestion7.Laboratory1.Theuncertaintyduetotheappliedstresswasdeterminedtakingloadcellanddimensionaluncertaintiesintoaccount.ThemathematicalevaluationwasmadeinaccordancewiththeGUM.Specimentemperaturewasmeasured,butwasimplicitlyneglected.Themodelingproblemwasmentioned,butnotconsideredasanuncertaintysource.Laboratory2.Thereportcontainsnouncertaintyevaluation.Theuncertaintiesintheloadcellandthemicrometerareconsidered,butneglectedwithreferencetothelargematerialscatter.Specimentemperaturewasmeasured.Modelingproblemsarementionedbyacommentregardingthechoiceofloadlevels.Laboratory3.Thereportcontainsnouncertaintyevaluation.However,theaccuracyofthe6machineisgivenandtheloadwascontrolledduringtheteststobewithinspecifiedlimits.Thebendingstressesweremeasuredononespecimen,buttheirinfluenceonthefatigueresultwasnottakenintoconsideration.Laboratory4.Theuncertaintiesintheloadcellandthedimensionalmeasurementsareconsideredinanevaluationofstressuncertainty.ThemethodfortheevaluationisnotinaccordancewiththeGUMmethod,butwasperformedbyaddingabsoluteerrors.Thebendingstressinfluenceandthecontrolsystemdeviationsareconsidered,butnotincludedintheuncertaintyevaluation.Thefailurecriterionismentionedandregardedasnegligible,andcorrosionismentionedasapossiblesourceofuncertainty.Laboratory5.Uncertaintiesintheloadcellandtheloadcontrolwereconsidered,andthelaboratorystatedinthereportthattheevaluationoftheloaduncertaintywasperformedaccordingtotheCIPMmethod.Laboratory6.Noreportwasprovided,butonlyexperimentalresultsandaWhalercurveestimate.Nolaboratoryreportedtheuncertaintyintheestimatedmaterialproperties,theWhalerparameters,butatmosttheuncertaintyintheappliedstress.Theoverallpictureoftheuncertaintyconsiderationsisthatonlyuncertaintysourcesthatarepossibletoestimatefromcalibrationreportsweretakenintoaccountinthefinalevaluation.Fig.1AllexperimentalresultsandestimatedWholecurvesfromthedifferentlaboratoriesNumberofcyclestofailureOneimportantsourcethatseverallaboratoriesmentionedisthebendingstressesinducedbymisalignmentinthetestingmachine,incorrectlymountedtestspecimensorincorrectspecimens.Theamountofbendingstresswasalsoestimatedinsomecases,butitsinfluenceon

注意事项

本文(外文翻译--关于北欧的疲劳实验室的比较—测量结果不确定值的反映.doc)为本站会员(英文资料库)主动上传,人人文库网仅提供信息存储空间,仅对用户上传内容的表现方式做保护处理,对上载内容本身不做任何修改或编辑。 若此文所含内容侵犯了您的版权或隐私,请立即通知人人文库网([email protected]),我们立即给予删除!

温馨提示:如果因为网速或其他原因下载失败请重新下载,重复下载不扣分。

copyright@ 2015-2017 人人文库网网站版权所有
苏ICP备12009002号-5