1、Designation: D 5023 07Standard Test Method forPlastics: Dynamic Mechanical Properties: In Flexure (Three-Point Bending)1This standard is issued under the fixed designation D 5023; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) 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 vi
3、sco-elasticproperties 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 pla
4、stic mate-rial or compositions 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 D 4065. Plot
5、s of the elastic(storage) 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 frequ
6、encies,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
7、this test method) the conditions underwhich 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 enginee
8、ring design.1.7 The values stated in 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 e
9、stablish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1This test method is equivalent to ISO 6721, Part 5.2. Referenced Documents2.1 ASTM Standards:2D 618 Practice for Conditioning Plastics for TestingD 4000 Classification Syst
10、em for Specifying Plastic Mate-rialsD 4065 Practice for Plastics: Dynamic Mechanical Proper-ties: Determination and Report of ProceduresD 4092 Terminology for Plastics: Dynamic MechanicalProperties2.2 ISO Standard:3ISO 6721, Part 5 PlasticsDetermination of Dynamic Me-chanical Properties Part 5: Flex
11、ural VibrationNon-Resonance Method3. Terminology3.1 Definitions: For definitions applicable to this testmethod refer to Terminology Standard D 4092.4. 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
12、of a loading nose midway between the supports.Using three-point bending, the test specimen is placed inmechanical linear displacement at fixed frequencies and ateither isothermal conditions or with linear temperature varia-tion. The elastic moduli or loss moduli, or both, of thepolymeric material sy
13、stem are measured.NOTE 2The particular method for measurement of the elastic and loss1This test method is under the jurisdiction ofASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.10 on Mechanical Properties.Current edition approved March 15, 2007. Published April 2
14、007. Originallyapproved in 1989. Last previous edition approved in 2001 as D 5023 - 01.2For 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 Summar
15、y page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohoc
16、ken, PA 19428-2959, United States.moduli and tan delta depends upon the 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 dat
17、a 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 moduli as a function of freque
18、ncy,temperature, or time. Plots of moduli and tan delta of a materialversus these variables can be used to provide a graphicalrepresentation indicative of functional properties, effectivenessof cure (thermosetting resin system), and damping behaviorunder specified conditions.5.3 This test method can
19、 be used to assess:5.3.1 Modulus as a function of temperature,5.3.2 Modulus as a function of frequency,5.3.3 The effects of processing treatment,5.3.4 Relative resin behavioral properties, including cureand damping.5.3.5 The effects of substrate types and orientation (fabri-cation) on modulus, and5.
20、3.6 The effects of formulation additives which mightaffect processability or performance.5.4 Before proceeding with this test method, refer to thespecification of the material being tested. Any test specimenpreparation, conditioning, dimensions, or testing parameters, orcombination thereof, covered
21、in the relevant ASTM materialsspecification shall take precedence over those mentioned in thistest method. If there are no relevant ASTM material specifica-tions, then the default conditions apply.6. Interferences6.1 Since small test specimen geometries are used, it isessential that the specimens be
22、 representative of the polymericmaterial being tested.7. Apparatus7.1 The function of the apparatus is to hold a rectangulartest specimen of a polymeric material system so that thematerial acts as the elastic and dissipative element in amechanically driven linear displacement system. Dynamicmechanic
23、al instruments described in this test method generallyoperate in a forced, constant amplitude mode at a fixedfrequency.7.2 The apparatus shall consist of the following:7.2.1 Loading Nose and SupportsThe loading nose andsupports shall have cylindrical surfaces having a sufficientradius to avoid exces
24、sive indentation or failure due to stressconcentration directly under the loading nose.7.2.2 Linear Deformation (strain)A device for applying acontinuous linear deformation (strain) to the specimen. In theforce-displacement device the deformation (strain) is appliedand then released (see Table 1 of
25、Practice D 4065).7.2.3 DetectorsA device or devices for determining de-pendent and independent experimental parameters such asforce (stress), deflection (strain), frequency, and temperature.Temperature should be measurable with a precision of 61C,frequency to 61 %, strain to 61 %, and force to 61%.7
26、.2.4 Temperature Controller and Oven A device forcontrolling the temperature, either by heating (in steps orramps), cooling (in steps or ramps), or maintaining a constantspecimen environment, or a combination thereof. A tempera-ture controller should be sufficiently stable to permit measure-ment of
27、environmental-chamber temperature to within 1C.7.3 Nitrogen, or other inert gas supply, for purging purposesif appropriate.8. Test Specimens8.1 The test specimens may be cut from sheets, plates, ormolded shapes, or may be molded to the desired finisheddimensions. Typically, the support span shall be
28、 16 (tolerance+4 or 2) times the depth of the beam. Specimens shall be longenough to allow overhanging on each end of at least 10 % ofthe support span, but in no case less than 6.4 mm (0.25 in.) oneach end. Overhang shall be sufficient to prevent the specimenfrom slipping through the supports. A typ
29、ical rectangular testbeam is 64 by 13 by 3 mm (2.5 by 0.5 by 0.125 in.) testedflatwise on a 50 mm (2 in.) support span, resulting in a span todepth ratio of 16. Rectangular test specimens of other dimen-sions can be used but should be clearly identified in the reportsection.9. Calibration9.1 Calibra
30、te the instrument using procedures recommendedby the manufacturer.10. Conditioning10.1 Condition the test specimens at 23.0 6 2C(73.4 6 3.6F) and 50 6 5 % relative humidity for not lessthan 40 h prior to test in accordance with Procedure A ofPractice D 618 unless otherwise specified by contract orre
31、levant ASTM material specification.11. Procedure11.1 Use an untested specimen for each measurement, suchas temperature or time sweep. Measure the width and depth ofthe specimen to the nearest 0.03 mm (0.001 in.) at its center.11.2 Center the specimen on the supports, with the long axisof the specime
32、n perpendicular to the loading nose and sup-ports.11.3 Pre-load the test specimen so that there is a positiveforce. Monitor the normal force to ensure adequate pre-loading.11.4 Select the desired frequency (or frequencies) for dy-namic linear displacement.11.5 Select the linear displacement amplitud
33、e within thelinear elastic region of the material being tested. If the linearelastic region is not known, perform a strain sweep at ambienttemperature to determine an appropriate amplitude.11.6 Temperature Sweep:11.6.1 Temperature increases should be controlled to 1 to2C/min for linear (ramp) increa
34、ses and to 2 to 5C/min witha minimum of 1-min thermal soak time for step increases.D502307211.6.2 The tan delta peak shall coincide with the dramaticchange in modulus through the glass-transition region.12. Calculation12.1 The equations listed in Practice D 4065 are used tocalculate the following im
35、portant rheological properties mea-sured in forced, nonresonant dynamic displacement:12.1.1 Storage (elastic) modulus in bending, E8,12.1.2 Loss (viscous) modulus in bending, E9,12.1.3 Complex modulus in bending, E*, and12.1.4 Tan delta, d*.13. Report13.1 Report the following information:13.1.1 Comp
36、lete identification of the material tested, includ-ing type, source, manufacturers code, number, form, principaldimensions, and previous processing, or thermal history, orboth, if available13.1.2 Direction of cutting and loading specimen, includingpre-load force,13.1.3 Conditioning procedure,13.1.4
37、Description of the instrument used for the test,13.1.5 Description of the calibration procedure,13.1.6 Identification of the sample atmosphere by gas com-position, purity, and rate used, if appropriate,13.1.7 Depth and width of specimen,13.1.8 Support span length,13.1.9 Support span-to-depth ratio,1
38、3.1.10 Radius of supports and loading nose,13.1.11 Frequency of dynamic displacement,13.1.12 Amplitude of displacement,13.1.13 Thermal gradient, if appropriate,13.1.14 Number of specimens tested,13.1.15 Table of data and results, including moduli and tandelta as a function temperature, frequency, st
39、rain, or time (asappropriate), and13.1.16 A plot of the modulus (moduli) and tan delta as afunction of temperature (see Fig. 1), frequency, strain, or time(as appropriate).14. Precision and Bias14.1 The repeatability standard deviation has been deter-mined for the materials shown in Table 1. A singl
40、e laboratoryevaluated four thermoplastic neat resins and composites andthe values shown were obtained with the same test method inthe same laboratory by the same operator using the sameequipment in the shortest practical period of time using testspecimens taken at random from a single quantity of ho
41、moge-neous material.15. Keywords15.1 dynamic mechanical rheological properties; elastic;flexural viscoelastic behavior; linear displacement; loss; stor-age modulus; tan deltaFIG. 1 Dynamic Mechanical Properties in Three-Point Bending(at Different Frequencies)TABLE 1 DMRT Three-Point Bending, Elastic
42、 Modulus, E* (E10Pa)or(E11dynes/cm2) at Selected TemperaturesMaterial Temperature, C40 60 80 100 120Polycarbonate:Mean 2.302 2.319 2.187 2.079 1.818Standard deviation 0.044 0.078 0.073 0.042 0.005Polypropylene:Mean 1.242 0.5744 0.2893 0.1835 . . .Standard deviation 0.255 0.0553 0.0151 0.0117 . . .AB
43、S:Mean 2.294 2.232 1.461 . . . . . .Standard deviation 0.011 0.004 0.052 . . . . . .Glass ReinforcedPolycarbonate:Mean 4.014 3.970 3.883 3.687 3.582Standard deviation 0.130 0.087 0.118 0.064 0.134D5023073SUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard
44、 since the last issue(D 5023 - 01) that may impact the use of this standard. (March 15, 2007)(1) Punctuation was corrected.(2) Portions were reworded for clarification.(3) Significance and Use subsection 5.4 was revised.(4) The ISO equivalency statement was revised and an ISOStandards subsection was
45、 added to the Referenced Documentssection.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and t
46、he riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision
47、of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shoul
48、dmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D5023074
