ASTM_D_5573_-_99_2012.pdf

Designation:D557399(Reapproved 2012)Standard Practice forClassifying Failure Modes in Fiber-Reinforced-Plastic(FRP)Joints1This standard is issued under the fixed designation D5573;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 practice covers the method of classifying,identifying,and characterizing the failure modes in adhesivelybonded fiber-reinforced-plastic(FRP)joints.The FRP used indeveloping this practice consists of glass fibers in a thermoset-polyester-resin matrix,commonly referred to as sheet-moldingcompound,or SMC.1.2 One objective of this practice is to present comprehen-sive definitions of possible failure modes to serve as a guide forcontracts,drawings,product specifications,and product perfor-mance.NOTE1Figures 2 through 11 referred to in the practice are containedin the ASTM adjunct,Color Photographs of Failure Modes.2Fig.2Side-by Side Comparison of Failure ModesFig.3Adhesive FailureFig.4Cohesive FailureFig.5Thin-Layer Cohesive FailureFig.6Fiber-Tear FailureFig.7Light-Fiber-Tear FailureFig.8Stock-Break FailureFig.9Mixed Failure40%Fiber-Tear Failure,60%Light-Fiber-Tear FiberFig.10Mixed Failure32%Adhesive Failure,68%Fiber-TearFailureFig.11Mixed Failure20%Adhesive Failure,60%Light-Fiber-Tear Failure,20%Fiber-Tear FailureNOTE2This practice may be used to describe the failure modesgenerated from testing,using procedures such as Test Methods D3163,D3164,D3165,D3807,D5041,D5868,and SAE J1525.1.3 The values stated in SI units are to be regarded as 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:3D907 Terminology of AdhesivesD3163 Test Method for Determining Strength of AdhesivelyBonded Rigid Plastic Lap-Shear Joints in Shear by Ten-sion LoadingD3164 Test Method for Strength Properties of AdhesivelyBonded Plastic Lap-Shear Sandwich Joints in Shear byTension LoadingD3165 Test Method for Strength Properties of Adhesives inShear by Tension Loading of Single-Lap-Joint LaminatedAssembliesD3807 Test Method for Strength Properties of Adhesives inCleavage Peel by Tension Loading(Engineering Plastics-to-Engineering Plastics)D5041 Test Method for Fracture Strength in Cleavage ofAdhesives in Bonded JointsD5868 Test Method for Lap Shear Adhesion for FiberReinforced Plastic(FRP)Bonding2.2 SAE Standard:SAE J1525 SAE Recommended PracticeLap Shear Testfor Automotive-Type Adhesives for Fiber ReinforcedPlastic(FRP)Bonding42.3 ASTM Adjuncts:Color Photographs of Failure Modes23.Terminology3.1 Definitions:3.1.1 Definitions may not appear outside of this practiceunless the following delimiting phrase is included:“relating totesting FRP bonded joints and ASTM Practice D5573.”3.2 Definitions of Terms Specific to This Standard:3.2.1 failure-mode classification,nrelating to testing FRPbonded joints,a classification that includes the seven classes offailure modes identified here:(1)adhesive failure,(2)cohesivefailure,(3)thin-layer cohesive failure,(4)fiber-tear failure,(5)1This practice is under the jurisdiction of ASTM Committee D14 on Adhesivesand is the direct responsibility of Subcommittee D14.40 on Adhesives for Plastics.Current edition approved Oct.1,2012.Published October 2012.Originallyapproved in 1994.Last previous edition approved in 2005 as D5573 99(2005).DOI:10.1520/D5573-99R12.2Available from ASTM International Headquarters.Order Adjunct No.ADJD5573.Original adjunct produced in 1993.3For 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.4Available from SAE International(SAE),400 Commonwealth Dr.,Warrendale,PA 15096-0001,http:/aerospace.sae.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 light-fiber-tear failure,(6)stock-break failure,and(7)mixedfailure(see 3.2.1.2 through 3.2.1.10).3.2.1.1 DiscussionFailure of a tested specimen is seldomconfined to a single mode,but rather is a combination of twoor more of the first six modes,such combination designated asmixed failure.Whenever possible,mixed failure should alwaysbe reported citing the class of failure present and the percent ofeach class.3.2.1.2 adhesive failure,ADH(or A),nrupture of theadhesively bonded joint,such that the separation appears to beat the adhesive-adherend interface.(Sometimes referred to asinterfacial failure.)(See Fig.1,Fig.2,and Fig.3.)3.2.1.3 DiscussionAfter failure