1、Designation: D 5279 01Standard Test Method forPlastics: Dynamic Mechanical Properties: In Torsion1This standard is issued under the fixed designation D 5279; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision
2、. 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 covers the use of dynamic mechanicalinstrumentation for gathering and reporting the viscoelasticproperties of t
3、hermoplastic and thermosetting resins and com-posite systems in the form of rectangular specimens moldeddirectly or cut from sheets, plates, or molded shapes. Thetorsional data generated may be used to identify the thermo-mechanical properties of a plastics material or composition.1.2 This test meth
4、od is intended to provide means fordetermining the modulus as a function of temperature ofplastics using nonresonant forced-vibration techniques, asoutlined in Practice D 4065. Plots of the elastic (storage), loss(viscous), and complex moduli and tan delta, as a function offrequency, time, or temper
5、ature are indicative of significanttransitions in the thermomechanical performance of the poly-meric material system.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 condit
6、ions. 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 andappr
7、opriate 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 he
8、alth practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no similar or equivalent ISO standard.2. Referenced Documents2.1 ASTM Standards:D 618 Practice for Conditioning Plastics and ElectricalInsulating Materials for Testing2D 4065 Practice for Determinin
9、g and Reporting DynamicMechanical Properties of Plastics3D 4092 Terminology Relating to Dynamic MechanicalMeasurements of Plastics33. Terminology3.1 For definitions applicable to this test method, refer toTerminology D 4092.4. Summary of Test Method44.1 This test method covers the determination of t
10、he shearmodulus of plastics using dynamic mechanical techniques. Atest specimen of rectangular cross section is tested in dynamictorsion. The specimen is gripped longitudinally between twoclamps. The specimen of known geometry is placed in me-chanical torsional displacement at either a fixed frequen
11、cy, orvariable frequencies at either isothermal conditions, or with alinear temperature increase. The elastic or loss modulus, orboth, of the polymeric material system are measured in torsion.5. Significance and Use5.1 This test method provides a simple means of character-izing the thermomechanical
12、behavior of plastics materialsusing very small amounts of material. The data obtained maybe used for quality control, research and development, andestablishment of optimum processing conditions.5.2 Dynamic mechanical testing provides a sensitivemethod for determining thermomechanical characteristics
13、 bymeasuring the elastic and loss moduli as a function offrequency, temperature, or time. Plots of moduli and tan deltaof a material versus temperature provide graphical representa-tions indicative of functional properties, effectiveness of cure(thermosetting resin system), and damping behavior unde
14、rspecified conditions.5.3 This test method can be used to assess1This 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 September 10, 2001. Published November 2001.Originall
15、y published as D 5279 92. Last previous edition D 5279 99.2Annual Book of ASTM Standards, Vol 08.01.3Annual Book of ASTM Standards, Vol 08.02.4The particular method for measurement of the elastic and loss moduli and tandelta depends upon the individual instruments operating principles.1*A Summary of
16、 Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.5.3.1 The modulus as a function of temperature,5.3.2 The modulus as a function of frequency,5.3.3 The effects of processing treatment
17、, including orien-tation,5.3.4 Relative resin behavioral properties, including cureand damping,5.3.5 The effects of substrate types and orientation (fabri-cation) on elastic modulus, and5.3.6 The effects of formulation additives that might affectprocessability or performance.6. Interferences6.1 Sinc
18、e small test specimen geometries are used, it isessential that the specimens be representative of the materialbeing tested.7. Apparatus7.1 The function of the apparatus is to hold a rectangulartest specimen so that the material acts as the elastic anddissipative element in a mechanically driven tors
19、ional system.Dynamic mechanical instruments operate at a forced, constantamplitude, and either at a fixed frequency, or variable frequen-cies.7.2 The apparatus shall consist of the following:7.2.1 Fixed MemberA fixed or essentially stationarymember carrying one grip.7.2.2 Movable MemberA movable mem
20、ber carrying asecond grip.7.2.3 GripsGrips for holding the test specimen betweenthe fixed member and the movable member. The grips shall bemechanically aligned, that is, they shall be attached to the fixedand movable member, respectively, in such a manner that theywill move into alignment as soon as
21、 any load is applied, so thatthe long axis of the test specimen will coincide with thedirection of the applied pull through the center line of the gripassembly.7.2.3.1 The test specimen shall be held in such a way thatslippage relative to the grips is minimized.7.2.4 Deformation (Strain Device)A dev
22、ice for applying acontinuous linear deformation (strain) to the specimen. In theforce-displacement device the deformation (strain) is appliedand then released. (See Table 1 of Practice D 4065.)7.2.5 DetectorsDevices for determining dependent andindependent experimental parameters, such as force (str
23、ess),deformation (strain), frequency, and temperature. Temperatureshould be measurable with a precision of 61C, frequency to61 %, and force to 61%.7.2.6 Temperature Controller and Oven A device forcontrolling the temperature, either by heating (in steps orramps), cooling (in steps or ramps), maintai
24、ning a constantspecimen environment, or a combination thereof. A tempera-ture controller should be sufficiently stable to permit measure-ment of environmental chamber temperature to within 1C.7.3 Nitrogen or other inert gas supply for purging purposes.8. Test Specimens8.1 The specimens may be cut fr
25、om sheets, plates or moldedshapes, or may be molded to the desired finished dimensions.Typically, the rectangular test specimen is 76 by 13 by 3 mm.Rectangular test specimens of other dimensions can be usedbut should be clearly identified in the report section. Thedistance between grips is approxima
26、tely 64 mm.9. Calibration9.1 Calibrate the instrument using procedures recommendedby the manufacturer.10. Conditioning10.1 ConditioningCondition the test specimens at 23.0 62.0C and 50 6 5 % relative humidity for not fewer than 40 hprior to test in accordance with Procedure A of Practice D 618for th
27、ose materials requiring conditioning.11. Procedure11.1 Use an untested specimen for each measurement.Measure the width and thickness of the specimen to the nearest0.03 mm at the center of the specimen.11.2 Clamp the test specimen between the movable andstationary members; use shim stock, if necessar
28、y, to minimizeslippage within the clamp.11.3 Preload the test specimen so that there is a positiveforce. Monitor the normal force to ensure adequate preloading.11.4 Measure to the nearest 0.03 mm the jaw separationbetween the movable and stationary members.11.5 Select the desired frequency (or frequ
29、encies) fordynamic-torsional displacement.11.6 Select the torsional-displacement amplitude.11.7 Temperature sweep.11.7.1 Temperature increases should be controlled to 1 to2C/min for linear increases or 2 to 5C/min with a minimumof 1-min thermal-soak time for step increases. This will allowcharacteri
30、zing of the modulus from the glassy region, throughthe glass-transition region, up to the softening or glassy-rubbery state.11.8 The tan-delta peak will coincide with a change in G8(elastic or storage) modulus through the glass-transition region.Another indication of the glass-transition is a maximu
31、m valueof the G9 (loss or viscous) modulus.12. Calculations12.1 The equations listed in Practice D 4065 are used tocalculate the important rheological properties measured inforced, nonresonant dynamic displacement:where:G8 = storage (elastic) modulus in torsion,G9 = loss (viscous) modulus in torsion
32、,G* = complex modulus in torsion, andd* = tan delta.13. Report13.1 Report the following information:13.1.1 Complete identification of the material tested, includ-ing type, source, manufacturers code, number, form, principaldimensions, and previous history,13.1.2 Description and direction of cutting
33、and loadingspecimen, including preload force,D 5279213.1.3 Conditioning procedure,13.1.4 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,13.1.7 Width and thicknes
34、s of specimen,13.1.8 Jaw separation distance,13.1.9 Frequency of dynamic displacement,13.1.10 Amplitude of displacement,13.1.11 Thermal gradient; heating rate,13.1.12 Number of specimens tested,13.1.13 Equations used to calculate values,13.1.14 Table of data and results, including moduli and tandelt
35、a as a function of temperature, and13.1.15 A plot of the modulus (moduli) and tan delta as afunction of temperature. (See Fig. 1.)14. Precision and Bias14.1 The repeatability standard deviation has been deter-mined for the following materials . Laboratory A evaluated apolyurethane sample and the val
36、ues in Table 1 were obtainedwith the same test method in the same laboratory by the sameoperator using the same equipment in the shortest practicalperiod of time using test specimens taken at random from asingle quantity of homogeneous material. Laboratory B testedthe same material and obtained the
37、results shown in Table 1.15. Keywords15.1 dynamic mechanical rheological properties; elastic;loss; storage; tan delta; torsional shear modulus; viscoelasticbehavior; viscousSUMMARY OF CHANGESThis section identifies the location of selected changes to this test method. For the convenience of the user
38、,Committee D20 has highlighted those changes that may impact the use of this test method. This section may alsoinclude descriptions of the changes or reasons for the changes, or both.D 527999:Revised Precision and Bias statement.(2) Added Summary of Changes.D 527901:(1) Title was changed.(2) Footnot
39、e 2 from the previous revision was deleted.FIG. 1 Dynamic Mechanical Modulus in Torsion as a Function of TemperatureTABLE 1 DMRT-Torsion, Elastic Modulus, G (E8Pascals) or (E9dynes/cm2) at Selected TemperaturesLaboratory 40C 0C 40C 80CAMean 3.773 0.2038 0.03624 0.03532StandardDeviation0.008 0.0067 0
40、.00032 0.00087BMean 3.568 0.2263 0.03206 0.02758StandardDeviation0.160 0.0461 0.00142 0.00023D 52793ASTM 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 dete
41、rmination of the validity of any such patent rights, and the 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
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43、t your comments have not received a fair hearing you shouldmake 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).D 52794
