ASTM_D_7750_-_12_2017.pdf

Designation:D775012(Reapproved 2017)Standard Test Method forCure Behavior of Thermosetting Resins by DynamicMechanical Procedures using an Encapsulated SpecimenRheometer1This standard is issued under the fixed designation D7750;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 method covers the use of dynamic mechanicalinstrumentation for determination and reporting of the thermaladvancement of cure behavior of thermosetting resin on aninert filler or fiber in a laboratory.It may also be used fordetermining the cure properties of filled resins and resinswithout reinforcements.These encapsulated specimens aredeformed in torsional shear using dynamic mechanical meth-ods.1.2 This method is intended to provide means for determin-ing the cure behavior of thermosetting resins on fibers over arange of temperatures from room temperature to 250C byforced-constant amplitude techniques(in accordance withPractice D4065).Plots of complex modulus,complexviscosity,and damping ratio or tan delta as a function of timeor temperature,or both,quantify the thermal advancement orcure characteristics of a resin or a resin on fiber.1.3 Test data obtained by this method is relevant andappropriate for optimizing cure cycles.1.4 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.4.1 ExceptionThe fahrenheit temperature measurementin 10.1 is provided for information only and is not consideredstandard.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 and health practices and determine the applica-bility 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:2D3878 Terminology for Composite MaterialsD4000 Classification System for Specifying Plastic Materi-alsD4065 Practice for Plastics:Dynamic Mechanical Proper-ties:Determination and Report of ProceduresD4092 Terminology for Plastics:Dynamic MechanicalPropertiesD4473 Test Method for Plastics:Dynamic Mechanical Prop-erties:Cure BehaviorD6507 Practice for Fiber Reinforcement Orientation Codesfor Composite MaterialsD7028 Test Method for Glass Transition Temperature(DMATg)of Polymer Matrix Composites by Dynamic Mechani-cal Analysis(DMA)E380 Practice for Use of the International System of Units(SI)(the Modernized Metric System)(Withdrawn 1997)33.Terminology3.1 Definitions:For most definitions applicable to thismethod refer to Terminology D4092.3.2 Definitions of Terms Specific to This Standard:3.2.1 Encapsulated Sample Parallel Plate RheometerDynamic Mechanical Analyzer apparatus that holds the speci-men under pressure within a confined cavity.The apparatus isdesigned to contain the resin within the specimen throughoutthe progress of the cure.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 Aug.1,2017.Published September 2017.Originallyapproved in 2012.Last previous edition approved as D775012.DOI:10.1520/D7750-12R17.2For 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 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 4.Summary of Test Method4.1 A small circular specimen is assembled from uncuredthermoset resin materials that correspond to a representation ofa composite part.This specimen is placed in mechanicaloscillation at a fixed frequency at either isothermal conditions,a linear temperature increase or a time-temperature relationsimulating a processing condition.The lower plate oscillatesand transmits torque from the lower plate through the sampleinto the upper plate.The resulting torque measured at the upperpl