Designation:D5803–97(Reapproved2002)AnAmericanNationalStandardStandardTestMethodforTensileStrengthatZero-Span(“WetZero-SpanTensile”)1ThisstandardisissuedunderthefixeddesignationD5803;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(e)indicatesaneditorialchangesincethelastrevisionorreapproval.INTRODUCTIONThedeterminationofthetensilestrengthofpaperandpaperboardwhendryorwetisdescribedinTestMethodsD828andD829,respectively.Intheseprocedures,thestandardeffectivespecimenlengthisdefinedbythetensiletestergripseparationatthestartofthetest.Thisstandardgripseparation,sometimescalledgagelengthorspan,is180mm(7.1in.).Othergagelengthsarepermittedforspecifictestingpurposesandaredescribedintherespectivetestmethods.Atagagelengthof180mm,themeasuredtensilestrengthofasheetofpaperorpaperboardisheavilyimpactedbysheetstructuralcharacteristicssuchasformation,basisweight,fiberorientation,andotherstructuralcharacteristics,andisessentiallyunchangedatgagelengthsrangingfrom50to200mm.Sheetstructuralcharacteristics,inturn,aredependentuponfundamentalpropertiesoftheindividualfibersandthewaythesepropertiesareimpactedthroughouttheentirepapermakingprocess.Thisistruewhetherthespecimensfortestingaretakenfromanearlyorintermediatepointinthepapermakingprocess,oraresampledafterthefinishedpapermaterialhasbeenproduced.Atagagelengthofzero,however,tensilestrengthishighlydependentuponfundamentalstrengthandotherqualitypropertiesofindividualfibersratherthansheetstructuralproperties.TensiledatameasuredatagagelengthofzeroistypicallyhigherthanthatmeasuredusingTestMethodD828,becausethestrengthofindividualfibers,asopposedtothecumulativeeffectoffiberproperties(particularlybonding)onsheetcharacteristicsisbeingmeasured.Tensilestrengthdataatagagelengthofzeromaybeusedtoassesstheretentionoffiberstrengthandfiberqualityparametersthroughtheentirefiberprocessingchain,therebyprovidi...
