ASTM_D_6115_-_97_2011.pdf

Designation:D611597(Reapproved 2011)Standard Test Method forMode I Fatigue Delamination Growth Onset of UnidirectionalFiber-Reinforced Polymer Matrix Composites1This standard is issued under the fixed designation D6115;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.1.Scope1.1 This test method determines the number of cycles(N)for the onset of delamination growth based on the openingmode I cyclic strain energy release rate(G),using the DoubleCantilever Beam(DCB)specimen shown in Fig.1.This testmethod applies to constant amplitude,tension-tension fatigueloading of continuous fiber-reinforced composite materials.When this test method is applied to multiple specimens atvarious G-levels,the results may be shown as a GN curve,asillustrated in Fig.2.1.2 This test method is limited to use with compositesconsisting of unidirectional carbon fiber tape laminates withsingle-phase polymer matrices.This limited scope reflects theexperience gained in round robin testing.This test method mayprove useful for other types and classes of composite materials,however,certain interferences have been noted(see Section 6.5of Test Method D5528).1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 ExceptionThe values provided in parentheses are forinformation only.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:2D883 Terminology Relating to PlasticsD2584 Test Method for Ignition Loss of Cured ReinforcedResinsD2651 Guide for Preparation of Metal Surfaces forAdhesiveBondingD2734 Test Methods for Void Content of Reinforced PlasticsD3171 Test Methods for Constituent Content of CompositeMaterialsD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsD5528 Test Method for Mode I Interlaminar Fracture Tough-ness of Unidirectional Fiber-Reinforced Polymer MatrixCompositesE4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE122 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 SystemE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE739 Practice for StatisticalAnalysis of Linear or LinearizedStress-Life(S-N)and Strain-Life(-N)Fatigue DataE1049 Practices for Cycle Counting in Fatigue AnalysisE1150 Definitions of Terms Relating to Fatigue(Withdrawn1996)33.Terminology3.1 Terminology D3878 defines terms relating to high-modulus fibers and their composites.Terminology D883 de-fines terms relating to plastics.Terminology E6 defines termsrelating to mechanical testing.Terminology E456 and PracticeE177 define terms relating to statistics.Definitions E1150defines terms relating to fatigue.In the event of conflict1This specification is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.06 onInterlaminar Properties.Current edition approved Aug.1,2011.Published December 2011.Originallyapproved in 1997.Last previous edition approved in 2004 as D6115 97(2004).DOI:10.1520/D6115-97R11.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 between terms,Terminology D3878 shall have precedenceover the other terminology standards.3.2 Definitions of Terms Specific to This Standard:3.2.1 crack opening mode(Mode I)fracture mode inwhich the delamination faces open away from each other andin which these faces do not undergo any relative sliding.3.2.2 cycles to onset of delamination growth,Nathe num-ber of fatigue cycles elapsed until the onset of delaminationgrowth from an implanted thin insert.3.2.3 fatigue delamination growth onset relationship,GNthe relationship between the peak cyclic value of strainenergy release rate to the number of fatigu