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【英文标准名称】:StandardGuideforAcousto-UltrasonicAssessmentofComposites,Laminates,andBondedJoints
【原文标准名称】:复合材料、叠层板材和粘接件的声学超声波评定的标准指南
【标准号】:ASTME1495-2002(2007)
【标准状态】:现行
【国别】:
【发布日期】:2002
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:E07.04
【标准类型】:(Guide)
【标准水平】:()
【中文主题词】:叠层板材;胶粘连接;机械试验;复合材料;试验
【英文主题词】:acousticemission;acousto-ultrasonics;bondedjoints;composites;laminates;materialscharacterization;mechanicalpropertiesassessment;nondestructiveevaluation;nondestructivetesting;stresswavefactor;ultrasonicattenuation
【摘要】:General8212;Conventionalultrasonicsshouldbeconsideredfirstforthedetectionofovertflawssuchasdelaminationsincomposites.Thereafter,AUshouldbeconsideredforcompositesthatareprovedtobefreeofmajorflawsordiscontinuities.TheAUmethodisintendedalmostexclusivelyforassessingthecollectiveeffectsofdisperseddefectsandsubcriticalflawpopulations.ThesearematerialaberrationsthatinfluenceAUmeasurementsandalsounderliemechanicalpropertyvariations,dynamicloadresponse,andimpactandfractureresistance.SpecificAdvantages8212;TheAUmethodcanbeusedtoevaluatecompositelaminateandbondqualityusingaccesstoonlyonesurfaceas,forexample,theexteriorsurfaceofpressurevessels.Itisunnecessarytoutilizeanglebeamfixturesbecausethemethodcanalwaysbeappliedwithprobesatnormalincidence.Themethodcanbeappliedusingdrycouplingwithelastomerpadsattachedtotheprobes,andthereisnoneedtoimmersetheexaminationobjectinwater.GeneralApplications8212;TheAUmethodwasdevisedtoassessdiffusediscontinuitypopulationsandanyassociatedchangesofthemechanicalpropertiesofcompositesandcomposite-likematerials.TheAUmethodhasbeenusedtoevaluatefiber-reinforcedcomposites(6),compositelaminates(7),filament-woundpressurevessels(8),adhesivebonds(9),paperandwoodproducts(10),andcableandrope(11).Themethodhasbeenshowntobeparticularlypracticalforassessingthestrengthofadhesivelybondedjoints.Ithasalsobeenshowntobeusefulforassessingmicroporosity(12),micro-cracking(13),hydrothermalaging(14),anddamageproducedbyimpacts(15)andfatigue(16).1.1Thisguideexplainstherationaleandbasictechnologyfortheacousto-ultrasonic(AU)method.Guidelinesaregivenfornondestructiveevaluation(NDE)offlawsandphysicalcharacteristicsthatinfluencethemechanicalpropertiesandrelativestrengthofcompositestructures(forexample,filament-woundpressurevessels),adhesivebonds(forexample,jointsbetweenmetalplates),andinterlaminarandfiber/matrixbondsinman-madecompositesandnaturalcomposites(forexample,woodproducts).1.2ThisguidecoverstechnicaldetailsandrulesthatmustbeobservedtoensurereliableandreproduciblequantitativeAUassessmentsoflaminates,composites,andbondedstructures.Theunderlyingprinciples,prototypeapparatus,instrumentation,standardization,examinationmethods,anddataanalysisforsuchassessmentsarecovered.LimitationsoftheAUmethodandguidelinesfortakingadvantageofitscapabilitiesarecited.1.3TheobjectiveofAUistoassesssubtleflawsandassociatedstrengthvariationsincompositestructuresandbondedjoints.Discontinuitiessuchaslargevoids,disbonds,orextendedlackofcontactatinterfacescanbeassessedbyotherNDEmethodssuchasconventionalultrasonics.1.4Additionalinformationmaybefoundinthepublicationscitedinthelistofreferencesattheendofthisguide.Thereferencedworksprovidebackgroundonresearch,applications,andvariousaspectsofsignalacquisition,processing,andinterpretation.1.5ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibi......
【中国标准分类号】:G38
【国际标准分类号】:19_100;83_180
【页数】:9P.;A4
【正文语种】:


【英文标准名称】:InformationTechnology-TelecommunicationsandInformationExchangeBetweenSystems-LocalAreaNetworks-MediaAccessControl(MAC)Bridges-SupplementforSupportbyIEEE802.11
【原文标准名称】:信息技术.系统间远程通信和信息交换.局域网.媒体访问控制(MAC)桥接线索.对IEEE802.11的补充
【标准号】:ANSI/IEEE802.1c-1998
【标准状态】:作废
【国别】:美国
【发布日期】:1998
【实施或试行日期】:
【发布单位】:美国国家标准学会(US-ANSI)
【起草单位】:ANSI
【标准类型】:()
【标准水平】:()
【中文主题词】:通信网;数据处理;局域网;电信
【英文主题词】:Communicationnetworks;Datacircuit;Dataprocessing;Informationtechnology;LAN;Localareanetworks;MAN;Metropolitanareanetworks;Metropolitanareas;Telecommunication;Telecommunications
【摘要】:Providestherequired802.11specificinformationtoISO10038(802.1D)standard.Itaddsasubclauseunder2.5,SupportoftheInternalSublayerServicebyspecificMACProcedures,tocoverbridgeoperationwithIEEE802.11MACs.
【中国标准分类号】:M11
【国际标准分类号】:35_110
【页数】:
【正文语种】:英语