Designation:C604−02(Reapproved2012)StandardTestMethodforTrueSpecificGravityofRefractoryMaterialsbyGas-ComparisonPycnometer1ThisstandardisissuedunderthefixeddesignationC604;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationofthetruespecificgravityofsolidmaterials,andisparticularlyusefulformaterialsthateasilyhydratewhicharenotsuitablefortestwithTestMethodC135.ThistestmethodmaybeusedasanalternateforTestMethodC135,TestMethodC128,andTestMethodC188fordeterminingtruespecificgravity.1.2Units—ThevaluesstatedinSIunitsaretoberegardedasstandard.Nootherunitsofmeasurementareincludedinthisstandard.1.2.1Exception—In7.3theequivalentSIunitisexpressedinparenthesis.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:2C128TestMethodforDensity,RelativeDensity(SpecificGravity),andAbsorptionofFineAggregateC135TestMethodforTrueSpecificGravityofRefractoryMaterialsbyWaterImmersionC188TestMethodforDensityofHydraulicCement3.SummaryofTestMethod3.1Thesampleispowderedtoensurepermeationofgasintoallpores.ForpracticalpurposesthisisassumedtobetruewhenthesamplepassesaNo.325(45-µm)sieve.Thevolumeofacarefullyweighedpowderedsamplewhichhasfirstbeenheatedtodriveoffmoistureandundesiredcombinedwaterismeasuredbythegas-comparisonpycnometer.Densityiscal-culatedfromthesampleweightingramsdividedbyitsvolumeincubiccentimetres.Thisisalsothespecificgravityofthesampleatroomtemperaturecomparedtowaterat4°C.3.2Theprincipleofthegas-comparisonpycnometerisasfollows:TherearetwochambersandtwopistonsassketchedinFig.1.Forpurposesofillustration,thech...
