【英文标准名称】:StandardPracticeforExposureofMetalsandAlloysbyAlternateImmersioninNeutral3.5%SodiumChlorideSolution
【原文标准名称】:在3.5%氯化钠中性溶液中用交替浸渍法的金属及合金暴露的标准实施规程
【标准号】:ASTMG44-1999(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】:铝;合金;工艺;磨损;评定;浸入试验;应力腐蚀;裂开;铝合金;耐腐蚀性;镁;腐蚀;有色金属;金属;镁合金
【英文主题词】:acceleratedcorrosiontest;alternateimmersiontest;aluminumalloys;ferrousalloys;qualitycontroltest;sodiumchloridesolution;stresscorrosioncracking
【摘要】:The3.5%NaClalternateimmersionprocedureisageneral,all-purposeprocedurethatproducesvalidcomparisonsformostmetals,particularlywhenspecimensareexposedathighlevelsofappliedstressorstressintensity.Whilethealternateimmersiontestisanacceleratedtestandisconsideredtoberepresentativeofcertainnaturalconditions,itisnotintendedtopredictperformanceinspecializedchemicalenvironmentsinwhichadifferentmodeofcrackingmaybeoperative.Forexample,itdoesnotpredicttheperformanceofaluminumalloysinhighlyacidicenvironmentssuchasheatedinhibitedredfumingnitricacid(IRFNA).Forsuchcases,theresultsofthealternateimmersiontestareofdoubtfulsignificanceuntilarelationshiphasbeenestablishedbetweenitandanticipatedserviceenvironments.Whilethispracticeisapplicableinsomedegreetoallmetals,itisnotequallydiscriminativeofallalloys,evenwithinthesamemetalsystem.Consequently,informationshouldbeestablishedtoallowcomparisonsofperformancesofthealloyofinterestinthealternateimmersiontestandinnaturalenvironments.Note28212;Thealternateimmersionconceptcanbeusefulforexposureofcorrosionspecimensinothersolutionsbecausetheprocedureandapparatusprovideacontrolledsetofconditions.Detailsofthisarebeyondthescopeofthispractice.1.1Thispracticecoversproceduresformakingalternateimmersionstresscorrosiontestsin3.5%sodiumchloride(NaCl)().Itisprimarilyfortestsofaluminumalloys(TestMethodG47)andferrousalloys,butmaybeusedforothermetalsexhibitingsusceptibilitytochlorideions.Itsetsforththeenvironmentalconditionsofthetestandthemeansforcontrollingthem.Note1Alternateimmersionstresscorrosionexposuresaresometimesmadeinsubstituteoceanwater(withoutheavymetals)preparedinaccordancewithSpecificationD1141.Thegeneralrequirementsofthispresentpracticearealsoapplicabletosuchexposuresexceptthatthereagentsused,thesolutionconcentration,andthesolutionpHshouldbeasspecifiedinSpecificationD1141.1.2Thispracticecanbeusedforbothstressedandunstressedcorrosionspecimens.Historically,ithasbeenusedforstress-corrosioncrackingtesting,butisoftenusedforotherformsofcorrosion,suchasuniform,pitting,intergranular,andgalvanic.1.3Thispracticeisintendedforalloydevelopmentandforapplicationswherethealternateimmersiontestistoserveasacontroltestonthequalityofsuccessivelotsofthesamematerial.Therefore,stricttestconditionsarestipulatedformaximumassurancethatvariationsinresultsareattributabletovariationsinthematerialbeingtested.1.4ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.
【中国标准分类号】:H25
【国际标准分类号】:77_060
【页数】:5P.;A4
【正文语种】: