ASTM_D_7264_-_D_7264M_-_15.pdf

Designation:D7264/D7264M15Standard Test Method forFlexural Properties of Polymer Matrix Composite Materials1This standard is issued under the fixed designation D7264/D7264M;the number immediately following the designation indicates theyear of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of lastreapproval.A superscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method determines the flexural stiffness andstrength properties of polymer matrix composites.1.1.1 Procedure AA three-point loading system utilizingcenter loading on a simply supported beam.1.1.2 Procedure BA four-point loading system utilizingtwo load points equally spaced from their adjacent supportpoints,with a distance between load points of one-half of thesupport span.NOTE1Unlike Test Method D6272,which allows loading at bothone-third and one-half of the support span,in order to standardizegeometry and simplify calculations this standard permits loading at onlyone-half the support span.1.2 For comparison purposes,tests may be conducted ac-cording to either test procedure,provided that the sameprocedure is used for all tests,since the two proceduresgenerally give slightly different property values.1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.Within the text,theinch-pound units are shown in brackets.The values stated ineach system are not exact equivalents;therefore,each systemmust be used independently of the other.Combining valuesfrom the two systems may result in nonconformance with thestandard.1.4 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.2.Referenced Documents2.1 ASTM Standards:2D790 Test Methods for Flexural Properties of Unreinforcedand Reinforced Plastics and Electrical Insulating Materi-alsD2344/D2344M Test Method for Short-Beam Strength ofPolymer Matrix Composite Materials and Their LaminatesD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsD5687/D5687M Guide for Preparation of Flat CompositePanels with Processing Guidelines for Specimen Prepara-tionD6272 Test Method for Flexural Properties of Unreinforcedand Reinforced Plastics and Electrical Insulating Materi-als by Four-Point BendingD6856 Guide for Testing Fabric-Reinforced“Textile”Com-posite MaterialsE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE122 Practice for Calculating Sample Size to Estimate,WithSpecified Precision,the Average for a Characteristic of aLot or ProcessE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE456 Terminology Relating to Quality and StatisticsE1309 GuideforIdentificationofFiber-ReinforcedPolymer-Matrix Composite Materials in DatabasesE1434 Guide for Recording Mechanical Test Data of Fiber-Reinforced Composite Materials in Databases2.2 Other Documents:ANSIY14.5-1999 DimensioningandTolerancingIncludes Inch and Metric3ANSI B46.1-1995 Surface Texture(Surface Roughness,Waviness and Lay)33.Terminology3.1 DefinitionsTerminology D3878 defines the terms re-lating to high-modulus fibers and their composites.Terminol-ogy E6 defines terms relating to mechanical testing.Terminol-ogy E456 and Practice E177 define terms relating to statistics.1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.04 onLamina and Laminate Test Methods.Current edition approved April 1,2015.Published May 2015.Originallyapproved in 2006.Last previous edition approved in 2007 as D7264/D7264M 07.DOI:10.1520/D7264_D7264M-15.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 In the event of a conflict between terms,Terminology D3878shall have precedence over the other documents.3.2 Definitions of Terms Specific to This Standard:3.2.1 flexural strength,nthe maximum stress at the outersurface of a flexure test specimen corresponding to the peakapplied force prior to flexural failure.3.2.2 flexural modulus,nthe ratio of stress range tocorresponding strain range for a test specimen loaded inflexure.3.3 Symbols:b=specimen widthCV=sample coef