Designation:C1351M−96(Reapproved2012)StandardTestMethodforMeasurementofViscosityofGlassBetween104Pa·sand108Pa·sbyViscousCompressionofaSolidRightCylinder[Metric]1ThisstandardisissuedunderthefixeddesignationC1351M;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethodcoversthedeterminationoftheviscos-ityofglassfrom104Pa·sto108Pa·sbymeasuringtherateofviscouscompressionofasmall,solidcylinder.21.2ThevaluesstatedinSIunitsaretoberegardedasthestandard.1.3Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappro-priatesafetyandhealthpracticesanddeterminetheapplica-bilityofregulatorylimitationspriortouse.2.ReferencedDocuments2.1ASTMStandards:3C338TestMethodforSofteningPointofGlassC965PracticeforMeasuringViscosityofGlassAbovetheSofteningPointC1350MTestMethodforMeasurementofViscosityofGlassBetweenSofteningPointandAnnealingRange(Approximately108Pa·stoApproximately1013Pa·s)byBeamBending(Metric)3.Terminology3.1parallelplateviscometer—adeviceusedtodeterminetheviscosityofglassfromapproximately104Pa·sto108Pa·sbymeasuringtherateofchangeinthicknessofacylindricalspecimenbetweenparallelplatesmovingperpendiculartotheircommoncentralaxis.Theequationforcalculatingviscositybytheparallelplatemethodis:η52πMgh530V~dh/dt!~2πh31V!~11αT!(1)where:η=viscosity,Pa·s,M=appliedload,g,g=accelerationduetogravity,980cm/s2,t=time,s,V=specimenvolume,cm3,h=specimenthicknessattimet,cm,dh/dt=compressionrate,cm/s,andα=glassmeancoefficientofthermalexpansion,25°Ctothemeasurementtemperature,T,m/m/°C.SeeNote1.NOTE1—Theterm(1+αT)correctsforthespecimendimensionalchangesduetothermalexpansion.Forlowthermalexpansionglasses,itcanbeignored.However,foraglasswithanαof20×10−6/°Catameasureme...
