ASTM_D_6341_-_21.pdf

Designation:D634121Standard Test Method forDetermination of the Linear Coefficient of ThermalExpansion of Plastic Lumber and Plastic Lumber ShapesBetween 30 and 140F(34.4 and 60C)1This standard is issued under the fixed designation D6341;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method covers the determination of the coef-ficient of linear thermal expansion for plastic lumber andplastic lumber shapes to two significant figures.The determi-nation is made by taking measurements with a caliper at threediscrete temperatures.At the test temperatures and under thestresses imposed,the plastic lumber shall have a negligiblecreep or elastic strain rate,or both,insofar as these propertieswould significantly affect the accuracy of the measurements.1.1.1 This test method details the determination of the linearcoefficient of thermal expansion of plastic lumber and plasticlumber shapes in their“as manufactured”form.As such,this isa test method for evaluating the properties of plastic lumber orshapes as a product and not a material property test method.1.2 The thermal expansion of plastic lumber and shapes iscomposed of a reversible component on which it is possible tosuperimpose changes in length due to changes in moisturecontent,curing,loss of plasticizer or solvents,release ofstresses,phase changes,voids,inclusions,and other factors.This test method is intended to determine the coefficient oflinear thermal expansion under the exclusion of non-linearfactors as far as possible.In general,it will not be possible toexclude the effect of these factors completely.For this reason,the test method can be expected to give a reasonable approxi-mation but not necessarily precise determination of the linearcoefficient of thermal expansion.1.3 Plastic lumber and plastic lumber shapes are currentlymade predominately with recycled plastics where the productis non-homogeneous in the cross-section.However,it ispossible that this test method will also be applicable to similarmanufactured plastic products made from virgin resins or otherplastic composite materials.1.4 The values stated in inch-pound units are to be regardedas the standard.The SI units given in parentheses are forinformation only.1.5 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this standard.1.6 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD4065 Practice for Plastics:Dynamic Mechanical Proper-ties:Determination and Report of ProceduresD6117 Test Methods for Mechanical Fasteners in PlasticLumber and ShapesE456 Terminology Relating to Quality and StatisticsE831 Test Method for Linear Thermal Expansion of SolidMaterials by Thermomechanical Analysis3.Terminology3.1 Definitions:3.1.1 Definitions of terms applying to these test methodsappear in Terminology D883.For terms relating to precisionand bias and associated issues,the terms used in this testmethod are in accordance with the definitions in TerminologyE456.3.1.2 plastic lumber,na manufactured product made pri-marily from plastic materials(filled or unfilled),typically usedas a building material for purposes similar to those of tradi-tional lumber,which is usually rectangular in cross-section.(Terminology D883)1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.20 on Plastic Lumber.Current edition approved Jan.15,2021.Published January 2021.Originallyapproved in 1998.Last previous edition approved in 2016 as D6341-16.DOI:10.1520/D6341-21.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Reco