1、Designation:D120414Standard Test Method forLinear Dimensional Changes of Nonrigid ThermoplasticSheeting or Film at Elevated Temperature1This standard is issued under the fixed designation D1204;the number immediately following the designation indicates the year oforiginal adoption or,in the case of
2、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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method
3、 covers the measurement of changes inlinear dimensions of nonrigid thermoplastic sheeting or filmthat result from exposure of the material to specified conditionsof elevated temperature and time.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to
4、 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 and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE1This test method and ISO 11501 address the same ma
5、tter,butdiffer in technical content(and results cannot be directly comparedbetween the two methods).2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD2732 Test Method for Unrestrained Linear ThermalShrinkage of Plastic
6、Film and SheetingD4000 Classification System for Specifying Plastic Materi-als2.2 ISO StandardISO 11501 Plastics:Film and SheetingDetermination ofDimensional Change on Heating33.Terminology3.1 DefinitionsTerms applicable to this test method aredefined in Terminology D883.4.Significance and Use4.1 Th
7、is test method is particularly applicable to nonrigidthermoplastic sheeting or film made by the calender or extru-sion process.The test gives an indication of lot-to-lot unifor-mity in regards to the degree of internal strains introducedduring processing.4.2 The heating medium in this test method is
8、 air and doesnot necessarily yield the same results as Test Method D2732,which uses a liquid medium.4.3 Before proceeding with this test method,review thespecifications of the material being tested,if available.Any testspecimen preparation,conditioning,dimensions,or testingparameters,or combination
9、thereof,covered in the relevantASTM material specification shall take precedence over thosementioned in this test method.If there are no relevant ASTMmaterial specifications,then the default conditions apply.Table1 of Classification System D4000 lists the ASTM materialstandards that currently exist.
10、5.Apparatus5.1 OvenA mechanical convection oven capable of main-taining a temperature of 100 6 1C.5.2 Scale,graduated in 0.25-mm(0.01-in.)divisions,30 cm(12 in.)or more in length.5.3 Thermometer,graduated in 1C divisions,with a rangesuitable for the test temperature used.5.4 Timer,graduated in minut
11、es.5.5 Template,25 by 25 cm(10 by 10 in.),for cutting testspecimens.5.6 Heavy Paper Sheets,approximately 40 by 40 cm(15 by15 in.),with smooth,wrinkle-and crease-free surfaces.5.7 Talc,finely ground.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct respons
12、ibility of Subcommittee D20.19 on Film,Sheeting,andMolded Products.Current edition approved March 1,2014.Published March 2014.Originallyapproved in 1952.Last previous edition approved in 2008 as D1204-08.DOI:10.1520/D1204-14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontac
13、t ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*A Summary of Change
14、s section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Test Specimens6.1 The test specimens shall be two pieces of the sheeting orfilm 25 by 25 cm(10 by 10 in.),cut with the aid of thetemplate,one f
15、rom either of the two transverse edges and onefrom the center of the sheet as shown in Fig.1.Each specimenshall be marked to show the direction of calendering orextrusion.The midpoint of each edge shall be marked for useas a reference point when final measurements are made.7.Conditioning7.1 Conditio
16、ningCondition the test specimens at 23 62C(73.4 6 3.6F)and 50 6 10%relative humidity for notless than 40 h prior to test in accordance with Procedure A ofPractice D618 unless otherwise specified by agreement or therelevantASTMmaterialspecification.Incasesofdisagreement,the tolerances shall be 61C(61.8F)and65%relative humidity.8.Procedure8.1 Place each specimen on the heavy paper that has beenlightly dusted with talc,and cover with a second piece ofdusted paper.Fasten the papers together with pap
