ASTM_D_7615_-_D_7615M_-_19.pdf

Designation:D7615/D7615M19Standard Practice forOpen-Hole Fatigue Response of Polymer Matrix CompositeLaminates1This standard is issued under the fixed designation D7615/D7615M;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 practice provides instructions for modifying staticopen-hole tensile and compressive strength test methods todetermine the fatigue behavior of composite materials sub-jected to cyclic tensile or compressive forces,or both.Thecomposite material forms are limited to continuous-fiber rein-forced polymer matrix composites in which the laminate isboth symmetric and balanced with respect to the test direction.The range of acceptable test laminates and thicknesses aredescribed in 8.2.1.2 This practice supplements Test Methods D5766/D5766M and D6484/D6484M with provisions for testingspecimens under cyclic loading.Several important test speci-men parameters,for example fatigue force(stress)ratio,are notmandated by this practice;however,repeatable results requirethat these parameters be specified and reported.1.3 This practice is limited to test specimens subjected toconstant amplitude uniaxial loading,where the machine iscontrolled so that the test specimen is subjected to repetitiveconstant amplitude force(stress)cycles.Either engineeringstress or applied force may be used as a constant amplitudefatigue variable.The repetitive loadings may be tensile,compressive,or reversed,depending upon the test specimenand procedure utilized.1.4 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.The values stated ineach system are not necessarily exact equivalents;therefore,toensure conformance with the standard,each system shall beused independently of the other,and values from the twosystems shall not be combined.1.4.1 Within the text the inch-pound units are shown inbrackets.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.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 PlasticsD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsD5766/D5766M Test Method for Open-Hole TensileStrength of Polymer Matrix Composite LaminatesD6484/D6484M Test Method for Open-Hole CompressiveStrength of Polymer Matrix Composite LaminatesE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE83 Practice for Verification and Classification of Exten-someter SystemsE122 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 StatisticsE467 Practice for Verification of Constant Amplitude Dy-namic Forces in an Axial Fatigue Testing SystemE739 Practice for StatisticalAnalysis of Linear or LinearizedStress-Life(S-N)and Strain-Life(-N)Fatigue DataE1823 Terminology Relating to Fatigue and Fracture Testing3.Terminology3.1 DefinitionsTerminology D3878 defines terms relatingto high-modulus fibers and their composites.Terminology1This practice is under the jurisdiction of ASTM Committee D30 on CompositeMaterials and is the direct responsibility of Subcommittee D30.05 on Structural TestMethods.Current edition approved April 1,2019.Published May 2019.Originallyapproved in 2011.Last previous edition approved in 2018 as D7615/D7615M11(2018).DOI:10.1520/D7615_D7615M-19.2For 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.Copyright 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 Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 D883 de