ASTM G39-1999(2005) 曲梁应力腐蚀试样制备和使用的标准实施规程

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【英文标准名称】:StandardPracticeforPreparationandUseofBent-BeamStress-CorrosionTestSpecimens
【原文标准名称】:曲梁应力腐蚀试样制备和使用的标准实施规程
【标准号】:ASTMG39-1999(2005)
【标准状态】:现行
【国别】:
【发布日期】:1999
【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】:G01.06
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:应力腐蚀;工艺;磨损;试样;腐蚀;准备;金属;使用说明
【英文主题词】:bent-beam;constantdeformation;constantload;elasticstrain;quantitativestress;stress-corrosioncracking;stress-corrosiontestspecimen
【摘要】:Thebent-beamspecimenisdesignedfordeterminingthestress-corrosionbehaviorofalloysheetsandplatesinavarietyofenvironments.Thebent-beamspecimensaredesignedfortestingatstresslevelsbelowtheelasticlimitofthealloy.Fortestingintheplasticrange,U-bendspecimensshouldbeemployed(seePracticeG30).Althoughitispossibletostressbent-beamspecimensintotheplasticrange,thestresslevelcannotbecalculatedforplastically-stressedthree-andfour-pointloadedspecimensaswellasthedouble-beamspecimens.Therefore,theuseofbent-beamspecimensintheplasticrangeisnotrecommendedforgeneraluse.1.1Thispracticecoversproceduresfordesigning,preparing,andusingbent-beamstress-corrosionspecimens.1.2Differentspecimenconfigurationsaregivenforusewithdifferentproductforms,suchassheetorplate.Thispracticeapplicabletospecimensofanymetalthatarestressedtolevelslessthantheelasticlimitofthematerial,andtherefore,theappliedstresscanbeaccuratelycalculatedormeasured(seeNote0).Stresscalculationsbythispracticearenotapplicabletoplasticallystressedspecimens.Itisthenatureofthesepracticesthatonlytheappliedstresscanbecalculated.Sincestress-corrosioncrackingisafunctionofthetotalstress,forcriticalapplicationsandproperinterpretationofresults,theresidualstress(beforeapplyingexternalstress)orthetotalelasticstress(afterapplyingexternalstress)shouldbedeterminedbyappropriatenondestructivemethods,suchasX-raydiffraction().1.3Testproceduresaregivenforstress-corrosiontestingbyexposuretogaseousandliquidenvironments.1.4Thebent-beamtestisbestsuitedforflatproductforms,suchassheet,strip,andplate.Forplatematerialthebent-beamspecimenismoredifficulttousebecausemoreruggedspecimenholdersmustbebuilttoaccommodatethespecimens.Adouble-beammodificationofafour-pointloadedspecimentoutilizeheaviermaterialsisdescribedin.1.5Theexposureofspecimensinacorrosiveenvironmentistreatedonlybrieflysinceotherpracticesdealwiththisaspect,forexample,SpecificationD1141,andPracticesG30,G36,G44,G50,andG85.TheexperimenterisreferredtoASTMSpecialTechnicalPublication425().1.6Thebent-beampracticegenerallyconstitutesaconstantstrain(deflection)test.Oncecrackinghasinitiated,thestateofstressatthetipofthecrackaswellasinuncrackedareashaschanged,andtherefore,theknownorcalculatedstressorstrainvaluesdiscussedinthispracticeapplyonlytothestateofstressexistingbeforeinitiationofcracks.1.7ThevaluesstatedinSIunitsaretoberegardedasstandard.Theinch-poundequivalentsinparenthesesareprovidedforinformation.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.(FormorespecificsafetyhazardinformationseeSectionand.)
【中国标准分类号】:H25
【国际标准分类号】:77_040_10;77_060
【页数】:8P.;A4
【正文语种】: