1、Designation:D502315Standard Test Method forPlastics:Dynamic Mechanical Properties:In Flexure(Three-Point Bending)1This standard is issued under the fixed designation D5023;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of l
2、ast 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 visco-elasticprope
3、rties 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 datagenerated,using three-point bending techniques,may be usedto identify the thermomechanical properties of a plastic mate-rial or com
4、positions using a variety of dynamic mechanicalinstruments.1.2 This test method is intended to provide means fordetermining the viscoelastic properties of a wide variety ofplastics materials using nonresonant,forced-vibration tech-niques in accordance with Practice D4065.Plots of the elastic(storage
5、)modulus;loss(viscous)modulus;complex modulusand tan delta as a function of frequency,time,or temperatureare indicative of significant transitions in the thermomechani-cal performance of polymeric material systems.1.3 This test method is valid for a wide range of frequencies,typically from 0.01 to 1
6、00 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 und
7、erwhich the data were obtained.1.5 Due to possible instrumentation compliance,the datagenerated are intended to indicate relative and not necessarilyabsolute property values.1.6 Test data obtained by this test method are relevant andappropriate for use in engineering design.1.7 The values stated in
8、SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.8 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 p
9、ractices and determine the applica-bility of regulatory limitations prior to use.NOTE1This test method is equivalent to ISO 6721,Part 5.2.Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD4000 Classification System for Specifying Plastic Materi-alsD4065 Prac
10、tice for Plastics:Dynamic Mechanical Proper-ties:Determination and Report of ProceduresD4092 Terminology for Plastics:Dynamic MechanicalProperties2.2 ISO Standard:3ISO 6721,Part 5 PlasticsDetermination of Dynamic Me-chanical Properties Part 5:Flexural VibrationNon-Resonance Method3.Terminology3.1 De
11、finitionsFor definitions applicable to this testmethod refer to Terminology D4092.4.Summary of Test Method4.1 A specimen of rectangular cross section is tested inflexure as a beam.The bar rests on two supports and is loadedby means of a loading nose midway between the supports.Using three-point bend
12、ing,the test specimen is placed inmechanical linear displacement at fixed frequencies with lineartemperature variation or variable frequencies at isothermalconditions.The elastic moduli or loss moduli,or both,of thepolymeric material system are measured.NOTE2The particular method for measurement of
13、the elastic and loss1This 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 1989.Last previous edition approved in 2007
14、 as D5023-07.DOI:10.1520/D5023-15.2For 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.3Available from American Nationa
15、l Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*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 moduli and tan delta depends upon th
16、e individual instruments operatingprinciples.5.Significance and Use5.1 This test method provides a simple means of character-izing the thermomechanical behavior of plastic compositionsusing very small amounts of material.The data obtained maybe used for quality control,research and development as wellas the establishment of optimum processing conditions.5.2 Dynamic mechanical testing provides a sensitive meansfor determining thermomechanical characteristics by measur-ing the elastic and loss mod
