ASTM_D_8336_-_21.pdf

Designation:D833621Standard Test Method forCharacterizing Tack of Prepregs Using a ContinuousApplication-and-Peel Procedure1This standard is issued under the fixed designation D8336;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 covers measurement of adhesion(tack)between partially cured(B-staged)composite prepreg and asubstrate in a peel test,under specified conditions.The test maybe conducted to measure tack between a flexible layer ofprepreg and another prepreg layer bonded to a rigid substrate(Method I)or a rigid metal substrate(Method II).This testmethod is primarily geared towards material characterizationfor automated material layup but can be modified for use withother processes.It is well known that material tack is a functionof multiple processing and environmental variables.Permis-sible composite prepreg materials include carbon,glass,andaramid fibers within a B-staged thermoset resin.1.2 Measured tack is specified in terms of a peel force at agiven specimen width.1.3 UnitsThe values stated in SI units are to be regardedas standard.The values given in parentheses after SI units areprovided for information only and are not considered standard.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 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:2A480/A480M Specification for General Requirements forFlat-Rolled Stainless and Heat-Resisting Steel Plate,Sheet,and StripD883 Terminology Relating to PlasticsD1781 Test Method for Climbing Drum Peel for AdhesivesD3167 Test Method for Floating Roller Peel Resistance ofAdhesivesD3878 Terminology for Composite MaterialsE4 Practices for Force Verification of Testing MachinesE122 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 Statistics3.Terminology3.1 DefinitionsTerminology D3878 defines terms relatingto composite materials.Terminology D883 defines termsrelating to plastics.Terminology E456 and Practice E177define terms relating to statistics.In the event of a conflictbetween terms,Terminology D3878 shall have precedenceover the other documents.4.Summary of Test Method4.1 A continuous application-and-peel method is employedto quantify tack at given test conditions(such as temperature)between one B-staged prepreg layer and a second B-stagedprepreg layer which is bonded to a rigid substrate,or betweena B-staged prepreg specimen and a rigid substrate.During atest,a prepreg specimen laid up on a substrate with or withoutanother prepreg layer is fed through the test fixture continu-ously(see Fig.1).The compaction roller presses the prepregagainst the substrate(and against the peel roller)at a control-lable force,bonding the prepreg to the substrate at a setapplication rate.Simultaneously,the prepreg is peeled from thesubstrate at a peel rate which is identical to the application rate.Data is collected over two phases where only the second phaseis related to adhesion.The peel force is determined from thedifference in the average force between the two phases.Measuring the peel force during a test gives a measure for thestrength of adhesion between prepreg and substrate at the givenpeel rate.1This test method is under the jurisdiction of ASTM Committee D30 onComposite Materials and is the direct responsibility of Subcommittee D30.03 onConstituent/Precursor Properties.Current edition approved Feb.1,2021.Published March 2021.DOI:10.1520/D8336-21.2For 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 Tr