ASTM_D_4255_-_D_4255M_-_15a.pdf

Designation:D4255/D4255M15aStandard Test Method forIn-Plane Shear Properties of Polymer Matrix CompositeMaterials by the Rail Shear Method1This standard is issued under the fixed designation D4255/D4255M;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 This test method determines the in-plane shear proper-ties of high-modulus fiber-reinforced composite materials byeither of two procedures.In Procedure A,laminates clampedbetween two pairs of loading rails are tested.When loaded intension the rails introduce shear forces in the specimen.InProcedure B,laminates clamped on opposite edges with atensile or compressive force applied to a third pair of rails inthe center are tested.1.2 Application of this test method is limited to continuous-fiber or discontinuous-fiber-reinforced polymer matrix com-posites in the following material forms:1.2.1 Laminates composed only of unidirectional fibrouslaminae,with the fiber direction oriented either parallel orperpendicular to the fixture rails.1.2.2 Laminates composed only of woven fabric filamentarylaminae with the warp direction oriented either parallel orperpendicular to the fixture rails.1.2.3 Laminates of balanced and symmetric construction,with the 0 direction oriented either parallel or perpendicular tothe fixture rails.1.2.4 Short-fiber-reinforced composites with a majority ofthe fibers being randomly distributed.NOTE1Additional test methods for determining in-plane shearproperties of polymer matrix composites may be found in Test MethodsD3518/D3518M,D5379/D5379M,D5448/D5448M,andD7078/D7078M.1.3 The reproducibility of this test method can be affectedby the presence of shear stress gradients in the gage section andstress concentrations at the gripping areas.Test MethodsD5379/D5379M and D7078/D7078M provide superior shearresponse in comparison to this test method,as their specimenconfigurations produce a relatively pure and uniform shearstress state in the gage section.1.4 The technical content of this standard has been stablesince 2001 without significant objection from its stakeholders.As there is limited technical support for the maintenance of thisstandard,changes since that date have been limited to itemsrequired to retain consistency with other ASTM D30 Commit-tee standards,including editorial changes and incorporation ofupdated guidance on micrometers and calipers,strain gagerequirements,speed of testing,specimen preconditioning andenvironmental testing.Future maintenance of the standard willonly be in response to specific requests and performed only astechnical support allows.1.5 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard.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.1.5.1 Within the text the inch-pounds units are shown inbrackets.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.2.Referenced Documents2.1 ASTM Standards:2D792 Test Methods for Density and Specific Gravity(Rela-tive Density)of Plastics by DisplacementD883 Terminology Relating to PlasticsD2584 Test Method for Ignition Loss of Cured ReinforcedResinsD2734 Test Methods for Void Content of Reinforced PlasticsD3171 Test Methods for Constituent Content of CompositeMaterials1This 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 May 15,2015.Published May 2015.Originallyapproved in 1983.Last previous edition approved in 2015 as D4255/D4255M 15.DOI:10.1520/D4255_D4255M-15A.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 States1 D3518/D3518M Test Method for In-Plane Shear Responseof Polymer Matrix Composite Materials by Tensile Test ofa 645 LaminateD3878 Terminology for Composite MaterialsD5229/D5229M Test Method for MoistureAbsorption Prop-erties and Equilibrium Conditioning of Polymer MatrixComposite MaterialsD5379/D5379M Test Method for Shear Properties of Com-posite Materials by the V-Notched Beam MethodD5