Designation:D6341−14aStandardTestMethodforDeterminationoftheLinearCoefficientofThermalExpansionofPlasticLumberandPlasticLumberShapesBetween–30and140°F(–34.4and60°C)1ThisstandardisissuedunderthefixeddesignationD6341;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thistestmethodcoversthedeterminationofthecoef-ficientoflinearthermalexpansionforplasticlumberandplasticlumbershapestotwosignificantfigures.Thedetermi-nationismadebytakingmeasurementswithacaliperatthreediscretetemperatures.Atthetesttemperaturesandunderthestressesimposed,theplasticlumbershallhaveanegligiblecreeporelasticstrainrate,orboth,insofarasthesepropertieswouldsignificantlyaffecttheaccuracyofthemeasurements.1.1.1Thistestmethoddetailsthedeterminationofthelinearcoefficientofthermalexpansionofplasticlumberandplasticlumbershapesintheir“asmanufactured”form.Assuch,thisisatestmethodforevaluatingthepropertiesofplasticlumberorshapesasaproductandnotamaterialpropertytestmethod.1.2Thethermalexpansionofplasticlumberandshapesiscomposedofareversiblecomponentonwhichitispossibletosuperimposechangesinlengthduetochangesinmoisturecontent,curing,lossofplasticizerorsolvents,releaseofstresses,phasechanges,voids,inclusions,andotherfactors.Thistestmethodisintendedtodeterminethecoefficientoflinearthermalexpansionundertheexclusionofnon-linearfactorsasfaraspossible.Ingeneral,itwillnotbepossibletoexcludetheeffectofthesefactorscompletely.Forthisreason,thetestmethodcanbeexpectedtogiveareasonableapproxi-mationbutnotnecessarilyprecisedeterminationofthelinearcoefficientofthermalexpansion.1.3Plasticlumberandplasticlumbershapesarecurrentlymadepredominatelywithrecycledplasticswheretheproductisnon-homogeneousinthecross-section.However,itispossiblethatthistestmethodwillalsobeapplicabletosimilarmanufacturedplasticprod...
