ASTM_D_3916_-_08.pdf

Designation:D391608Standard Test Method forTensile Properties of Pultruded Glass-Fiber-ReinforcedPlastic Rod1This standard is issued under the fixed designation D3916;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 describes a procedure for determiningthe tensile properties of pultruded,glass-fiber-reinforced ther-mosetting plastic rod of diameters ranging from 3.2 mm(18in.)to 25.4 mm(1 in.).Little test specimen preparation is required;however,reusable aluminum tab grip adapters(Fig.1)ofappropriate size are required to prevent premature failure of thespecimens at the grips.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 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.Specific hazardsstatements are given in Note 3 and Note 4.NOTE1There is no known ISO equivalent to this test method.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD638 Test Method for Tensile Properties of PlasticsE4 Practices for Force Verification of Testing MachinesE83 Practice for Verification and Classification of Exten-someter Systems3.Significance and Use3.1 The high axial-tensile strength and the low transverse-compressive strength of pultruded rod combine to present someunique problems in determining the tensile strength of thismaterial with conventional test grips.The high transverse-compressive forces generated in the conventional method ofgripping tend to crush the rod,thereby causing prematurefailure.In this test method,aluminum-alloy tabs contoured tothe shape of the rod reduce the compressive forces imparted tothe rod,thus overcoming the deleterious influence of conven-tional test grips.3.2 Tensilepropertiesareinfluencedbyspecimenpreparation,strain rate,thermal history,and the environmentalconditions at the time of testing.Consequently,where precisecomparative results are desired,these factors must be carefullycontrolled.3.3 Tensile properties provide useful data for many engi-neering design purposes.However,due to the high sensitivityof these properties to strain rate,temperature,and otherenvironmental conditions,data obtained by this test methodshould not,by themselves,be considered for applicationsinvolving load-time scales or environmental conditions thatdiffer widely from the test conditions.In cases where suchdissimilarities are apparent,the sensitivities to strain rate,including impact and creep,as well as to environment,shouldbe determined over a wide range of conditions as dictated bythe anticipated service requirements.4.Apparatus4.1 Water-Cooled Diamond or Tungsten-Carbide Saw,forcutting rod to size.4.2 Micrometer,reading to at least 0.025 6 0.000 mm(0.001 6 0.000 in.),for measuring the width and thickness ofthe test specimens.The thickness of nonrigid plastics(rein-forced pultruded products are rigid)should be measured with adial micrometer that exerts a pressure of 25 6 kPa(3.6 6 0.7psi)on the specimen and measures the thickness to within0.025 mm(0.001 in.).The anvil of the micrometer shall be atleast 30 mm(1.4 in.)in diameter and parallel to the face of thecontact foot.4.3 Universal Testing Machine,verified in accordance withPractices E4,having a capacity of at least 530 kN(120 000lbf)to permit the testing of 25.4 mm(1 in.)diameter rod.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.18 on Reinforced Thermoset-ting Plastics.Current edition approved March 1,2008.Published March 2008.Originallyapproved in 1980.Last previous edition approved in 2002 as D3916-02.DOI:10.1520/D3916-08.2For 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 Smaller-diameter rod may be tested on lower-capacityequipment,commensurate with the anticipated tensile strengthof such rod.4.4 ExtensometerA suitable instrument for determiningthe distance between two designated points located within thegage length of the test specimen as the specimen is stretched.It is desirable,but not essential,that this instrument automat