Designation:C272/C272M−18StandardTestMethodforWaterAbsorptionofCoreMaterialsforSandwichConstructions1ThisstandardisissuedunderthefixeddesignationC272/C272M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope1.1Thistestmethodcoversthedeterminationoftherelativeamountofwaterabsorptionbyvarioustypesofsandwichconstructioncorematerialswhenimmersedinwater,orwhensubjectedtoahighrelativehumidityenvironment.Permissiblecorematerialformsincludethosewithcontinuousbondingsurfaces(suchasbalsawoodandfoams)aswellasthosewithdiscontinuousbondingsurfaces(suchashoneycomb).1.2ThevaluesstatedineitherSIunitsorinch-poundunitsaretoberegardedseparatelyasstandard.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedindependentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.1.2.1Withinthetexttheinch-poundunitsareshowninbrackets.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.4Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D883TerminologyRelatingtoPlasticsD1193SpecificationforReagentWaterD3878TerminologyforCompositeMaterialsE122PracticeforCalculatingSampleSizetoEstimate,WithSpecifiedPrecision,theAverageforaCharacteristicofaLotorProcessE177PracticeforUseoftheTermsPrecis...
