Designation:D5470−17StandardTestMethodforThermalTransmissionPropertiesofThermallyConductiveElectricalInsulationMaterials1ThisstandardisissuedunderthefixeddesignationD5470;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.ThisstandardhasbeenapprovedforusebyagenciesoftheU.S.DepartmentofDefense.1.Scope*1.1Thisstandardcoversatestmethodformeasurementofthermalimpedanceandcalculationofanapparentthermalconductivityforthermallyconductiveelectricalinsulationmaterialsrangingfromliquidcompoundstohardsolidmate-rials.1.2Theterm“thermalconductivity”appliesonlytohomo-geneousmaterials.Thermallyconductiveelectricalinsulatingmaterialsareusuallyheterogeneousandtoavoidconfusionthistestmethoduses“apparentthermalconductivity”fordetermin-ingthermaltransmissionpropertiesofbothhomogeneousandheterogeneousmaterials.1.3ThevaluesstatedinSIunitsaretoberegardedasstandard.1.4Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafety,health,andenvironmentalpracticesanddeter-minetheapplicabilityofregulatorylimitationspriortouse.1.5Thisinternationalstandardwasdevelopedinaccor-dancewithinternationallyrecognizedprinciplesonstandard-izationestablishedintheDecisiononPrinciplesfortheDevelopmentofInternationalStandards,GuidesandRecom-mendationsissuedbytheWorldTradeOrganizationTechnicalBarrierstoTrade(TBT)Committee.2.ReferencedDocuments2.1ASTMStandards:2D374TestMethodsforThicknessofSolidElectricalInsu-lation(Metric)D0374_D0374ME691PracticeforConductinganInterlaboratoryStudytoDeterminethePrecisionofaTestMethodE1225TestMethodforThermalConductivityofSolidsUsingtheGuarded-Comparative-LongitudinalHeatFlowTechnique3.Terminology3.1DefinitionsofTermsSpecifictoThisStandard:3.1.1apparentthermalconductivity(λ...
