ASTM_D_1708_-_13.pdf

Designation:D170813Standard Test Method forTensile Properties of Plastics by Use of MicrotensileSpecimens1This standard is issued under the fixed designation D1708;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This test method covers certain material specificationsfor which a history of data has been obtained using the standardmicrotensile specimen.In general,this test method is super-seded for general use by either Test Methods D882 or TestMethod D638.The very small Type V specimen in TestMethod D638 is the recommended specimen when limitedamounts of material are available.1.2 This test method covers the determination of the com-parative tensile strength and elongation properties of plastics inthe form of standard microtensile test specimens when testedunder defined conditions of pretreatment,temperature,humidity,and testing machine speed.This method is applicablewhen using specimens of any thickness up to 3.2 mm(18in.),including thin films.1.3 This test method cannot be used for the determination ofmodulus of elasticity.For the determination of modulus,seeTest Method D638 or Test Methods D882.1.4 Test data obtained by this test method are relevant andappropriate for use in engineering design.1.5 The values stated in SI units are to be regarded asstandard.The values given in parentheses are for informationonly.1.6 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 and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE1There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD638 Test Method for Tensile Properties of PlasticsD882 Test Method for Tensile Properties of Thin PlasticSheetingD883 Terminology Relating to PlasticsD4000 Classification System for Specifying Plastic Materi-alsD5947 Test Methods for Physical Dimensions of SolidPlastics SpecimensD6988 Guide for Determination of Thickness of Plastic FilmTest SpecimensE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsDefinitions of terms applying to this testmethod appear in Terminology D883 and Test Method D638,Annex A2.4.Significance and Use4.1 This test method provides data for quality control andacceptance or rejection under specifications.4.2 Before proceeding with this test method,referenceshould be made to the ASTM specification of the materialbeing tested.Any test specimen preparation,conditioning,dimensions,or testing parameters,or combination thereof,covered in the materials specification shall take precedenceover those mentioned in this test method.If there are nomaterial specifications,then the default conditions hereinapply.Table 1 of Classification System D4000 lists the ASTMmaterials standards that currently exist.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.Current edition approved Sept.1,2013.Published September 2013.Originallyapproved in 1959.Last previous edition approved in 2010 as D1708-10.DOI:10.1520/D1708-13.2For 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 States1 5.Apparatus5.1 The apparatus shall be as specified in Test MethodD638,with the following exceptions:5.1.1 GripsUse serrated grips faces with care,since yield-ing or tearing at the grips may interfere with measurement ofelongation even when the specimen breaks in the reducedsection.Grips with rubber coated faces are recommended forthin specimens.Self-tightening grips that move as they tightenand result in a change in the grip separation between upper andlower grips are not satisfactory for this test method.If thespecimen tab is not long enough to prevent the grip faces fromcocking,use shims to provide more uniform clamping.5.1.2 Drive MechanismThe velocity of the drive mecha-nism shall be regulated as specified in Section 8.5.1.3 The fixed and movable members,drive mechanism,and grips shall be constructed of such materials and in suchproportions that,after grip slack is taken up,the total elasticlongitudinal deformation of the system constituted by