ASTM_D_5418_-_15.pdf

Designation:D541815Standard Test Method forPlastics:Dynamic Mechanical Properties:In Flexure(DualCantilever Beam)1This standard is issued under the fixed designation D5418;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.Scope*1.1 This test method outlines the use of dynamic mechanicalinstrumentation for determining and reporting the viscoelasticproperties of thermoplastic and thermosetting resins and com-posite systems in the form of rectangular bars molded directlyor cut from sheets,plates,or molded shapes.The elasticmodulus data generated may be used to identify the thermo-mechanical properties of a plastics material or composition.1.2 This test method is intended to provide a means fordetermining the viscoelastic properties of a wide variety ofplastics using nonresonant,forced-vibration techniques asoutlined in Practice D4065.In particular,this method identifiesthe procedures used to measure properties using what is knownas a dual-cantilever beam flexure arrangement.Plots of theelastic(storage)modulus,loss(viscous)modulus,and complexmodulus,and tan delta as a function of frequency,time,ortemperature are indicative of significant transitions in thethermomechanical performance of the polymeric material sys-tems.1.3 This test method is valid for a wide range of frequencies,typically from 0.01 to 100 Hz.1.4 Apparent discrepancies may arise in results obtainedunder differing experimental conditions.These apparent differ-ences from results observed in another study can usually bereconciled,without changing the observed data,by reporting infull(as described in this test method)the conditions underwhich the data were obtained.1.5 Test data obtained by this test method are relevant andappropriate for use in engineering design.1.6 The values stated in SI units are to be regarded asstandard.1.7 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.NOTE1There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD4065 Practice for Plastics:Dynamic Mechanical Proper-ties:Determination and Report of ProceduresD4092 Terminology for Plastics:Dynamic MechanicalPropertiesD5279 Test Method for Plastics:Dynamic Mechanical Prop-erties:In Torsion3.Terminology3.1 For definitions applicable to this practice see Terminol-ogy Standard D4092.4.Summary of Test Method4.1 This test method covers the determination of the elasticmodulus of plastics using dynamic mechanical techniques.Abar of rectangular cross section is tested as a beam in dynamiclinear displacement or bending.The dual-cantilever beamspecimen is gripped between two clamps.The specimen ofknown geometry is placed in mechanical linear displacement,with the displacement strain or deformation applied at thecenter of the dual-cantilever beam.The forced-strain displace-ment is at either a fixed frequency or variable frequencies,andat either isothermal conditions or with a linear temperaturevariation.The elastic or loss modulus,or both,of the polymericmaterial system are measured in flexure.35.Significance and Use5.1 This test method provides a simple means of character-izing the thermomechanical behavior of plastic compositionsusing a very small amount of material.Since small test1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.Current edition approved July 1,2015.Published July 2015.Originally approvedin 1993.Last previous edition approved in 2007 as D5418-07.DOI:10.1520/D5418-15.2For 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 particular method for measurement of the elastic and loss moduli and tandelta depends upon the individual instruments operating principles.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 specimen geometries are used,it is essential that the specimensbe representative of the material being tested.The dataobtained can be used for quality control and/or research anddevelopment purposes.For some classes of materials,such asthermosets,it can also be used to establish optimum processingconditions.5.2 Dynamic mechanical testing provides a sensitive meansfor determining thermomechanical characteris