1、Designation: E1867 11Standard Test Method forTemperature Calibration of Dynamic Mechanical Analyzers1This standard is issued under the fixed designation E1867; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 test method describes the temperature calibrationof dynamic mechanical analyzers (DMA) from 150 C to500 C.1.2 The values sta
3、ted in SI units are to be regarded asstandard.1.3 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 regul
4、atory limitations prior to use. Specific precau-tionary statements are given in Note 7.2. Referenced Documents2.1 ASTM Standards:2E473 Terminology Relating to Thermal Analysis and Rhe-ologyE1142 Terminology Relating to Thermophysical PropertiesE2161 Terminology Relating to Performance Validation inT
5、hermal Analysis3. Terminology3.1 Definitions:3.1.1 The technical terms used in this test method aredefined in Terminologies E473, E1142, and E2161, includingdynamic mechanical analysis, frequency, stress, strain andstorage modulus.4. Summary of Test Method4.1 An equation is developed for the linear
6、correlation ofexperimentally observed program or sensor temperature andthe actual melting temperature for known melting referencematerials. This is accomplished by loading melting pointreference materials into a polymer tube, or wrapping them withpolymer tape and subjecting it to a mechanical oscill
7、ation ateither fixed or resonant frequency. The extrapolated onset ofmelting is identified by a rapid decrease in the ordinate signal(the apparent storage modulus, stress, inverse strain or probeposition). This onset is used for temperature calibration withtwo melting point reference materials.5. Si
8、gnificance and Use5.1 Dynamic mechanical analyzers monitor changes in theviscoelastic properties of a material as a function of tempera-ture and frequency, providing a means to quantify thesechanges. In most cases, the value to be assigned is thetemperature of the transition (or event) under study.
9、Therefore,the temperature axis (abscissa) of all DMA thermal curvesmust be accurately calibrated by adjusting the apparent tem-perature scale to match the actual temperature over thetemperature range of interest.6. Interferences6.1 An increase or decrease in heating rates or change inpurge gas type
10、or rate from those specified may alter results.6.2 Once the temperature calibration procedure has beenexecuted, the measuring temperature sensor position shall notbe changed, nor shall it be in contact with the specimen orspecimen holder in a way that would impede movement. If thetemperature sensor
11、position is changed or is replaced, then theentire calibration procedure shall be repeated.6.3 Once the temperature calibration has been executed, thegeometry deformation (bending study, versus tensile, and thelike) shall not be changed. If the specimen testing geometrydiffers significantly from tha
12、t of the calibrants, then thecalibration shall be repeated in the geometry matching that ofspecimen testing.6.4 This method does not apply to calibration for shear orcompressive geometries of deformation.7. Apparatus7.1 The function of the apparatus is to hold a specimen ofuniform dimension so that
13、the specimen acts as the elastic anddissipative element in a mechanically oscillated system. Dy-namic mechanic analyzers typically operate in one of severalmodes as outlined in Table 1.1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsib
14、ility of Subcommittee E37.10 on Funda-mental, Statistical and Mechanical Properties.Current edition approved Aug. 1, 2011. Published September 2011. Originallyapproved in 1997. Last previous edition approved in 2006 as E1867 06. DOI:10.1520/E1867-11.2For referenced ASTM standards, visit the ASTM web
15、site, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United Sta
16、tes.7.1.1 The apparatus shall consist of the following:7.1.1.1 ClampsAclamping arrangement that permits grip-ping of the specimen. This may be accomplished by clampingat both ends (most systems), one end (for example, torsionalpendulum) or neither end (for example, free bending betweenknife edges).7
17、.1.1.2 Device to Apply Oscillatory Stress or StrainAdevice for applying an oscillatory deformation (strain) oroscillatory stress to the specimen. The deformation may beapplied and then released, as in freely vibrating devices, orcontinually applied, as in forced vibration devices.7.1.1.3 DetectorA d
18、evice or devices for determining thedependent and independent experimental parameters, such asforce (stress), deformation (strain), frequency, and temperature.Temperature shall be measurable with an accuracy of 60.1 C,force to 61 % and frequency to 61%.7.1.1.4 Temperature Controller and OvenA device
19、 forcontrolling the specimen temperature, either by heating, cool-ing (in steps or ramps), or by maintaining a constant experi-mental environment. The temperature programmer shall besufficiently stable to permit measurement of specimen tempera-ture to 0.1 C.7.1.1.5 A Data Collection Device, to provi
20、de a means ofacquiring, storing, and displaying measured or calculatedsignals, or both. The minimum output signals required fordynamic mechanical analysis are storage modulus, loss modu-lus, tangent delta, temperature, and time.NOTE 1Some instruments, suitable for this test, may display onlylinear o
21、r logarithmic storage modulus while others may display linearand/or logarithmic storage modulus. Care must be taken to use the samemodulus scale when comparing unknown specimens, and in the compari-son of results from one instrument to another.7.2 High Temperature Polymer Tubing such as PTFE (Poly-t
22、etrafluoroethylene) or PEEK (Polyetheretherketone), of 3-mmoutside diameter and wall thickness of 0.5-mm (0.002 in.)3inner diameter may be used for low temperature standards (thatis, less than 160 C). The tubing may be sealed with suitablemelting temperature wax plugs, or similar sealant.NOTE 2PTFE
23、tubing is selected for its flexibility and inert nature forthe solvents in use at the temperatures of interest. Furthermore itstransitions should not produce any interference in the DMA signal withinthe range of the suggested calibrant materials. PEEK provides increasedstiffness for ease of loading.
24、 For other temperature ranges, a suitablereplacement for the high temperature polymer tubing may be used.7.3 Where the melting material is to be confined to a tube7.4 PTFE Tape, for wrapping metal point standards.7.5 Calibration MaterialsOne or more suitable materialspresented in Table 2.7.6 Caliper
25、s or other length measuring device capable ofmeasuring dimensions (or length) within 610 m.8. Reagents and Materials8.1 Dry nitrogen, helium, or other inert gas supplied forpurging purposes and especially to ensure that moisture con-densation and ice formation is avoided when measurementsinvolve tem
26、peratures below the dew point.9. Calibration and Standardization9.1 Prepare the instrument for operation as dexcribed by themanufacturer in the operations manual10. Procedure10.1 Two Point CalibrationFor the purposes of this pro-cedure, it is assumed that the relationship between observedextrapolate
27、d onset temperature (To) and actual specimen tem-perature (Tt) is a linear one governed by the equation:Tt5 To3 S! 1 I (1)where: S and I are the slope and intercept of a straight line,respectively.10.2 Select two calibration standards near the temperaturerange of interest. The standards should be as
28、 close to the upperand lower temperature limits used for the subsequent testmaterials as practical.NOTE 3The purpose of the polymer encapsulation is to providethermal resistance between the test specimen and the environment similarto that offered by polymer test specimens. In some testing geometries
29、 itmay be possible to perform the test directly on the metal melting pointreference materials without encapsulation. (See Appendix X2.)10.2.1 Encapsulation technique for low temperature (liquid)standards where the melting temperature does not exceed100 C.10.2.1.1 Fill the polymer tubing with the cal
30、ibration mate-rial or wrap a solid calibrant with PTFE tape. Calibrant must3Lotti, C., and Canevarolo. S.V., “Temperature Calibration of a DynamicMechanical Thermal Analyzer,” Polymer Testing, Vol 17, 1998, pp. 523530.TABLE 1 Dynamic Mechanical Analyzer Modes of OperationModeMechanical ResponseTensi
31、on Flexural Torsion CompressionFree/decA. . X .Forced/res/CAA. X X .Forced/fix/CAAXX XForced/fix/CSAX X . XAFree = free oscillation; dec = decaying amplitude; forced = forced oscillation;CA = constant amplitude; res = resonant frequency; fix = fixed frequency;CS = controlled stress.TABLE 2 Calibrati
32、on MaterialsMaterialTransition TemperatureAReferenceC KCyclopentane (solid-solid) 151.16 121.99 X1.1Cyclopentane (solid-solid) 135.06 138.09 X1.1n-Heptane 90.56 182.65 X1.2Cyclohexane 87.06 186.09 X1.3n-Octane 56.76 216.39 X1.1n-Decane 26.66 246.49 X1.1n-Dodecane 9.65 263.5 X1.1Water 0.01 273.16 X1.
33、4Cyclohexane 6.54 279.69 X1.3Indium 156.5985 495.7485 X1.4Tin 231.928 505.078 X1.4Lead 327.462 600.612 X1.5ZincB419.527 692.677 X1.4AThe values in this table were determined under special, highly accurate testconditions that are not attainable or applicable to this test method. The actualprecision o
34、f this test method is given in Section 13.BAmalgamates with aluminum. Do not heat above 430 C.E1867 112extend to the ends of the clamping geometry and must haveuniform dimensions with respect to width.NOTE 4For solid calibrants, a wire of dimensions suitable for testingshould be used.10.3 Measure th
35、e length and for solid calibrants the diam-eter as well, of specimens.10.4 Mount the specimen in accordance with the procedurerecommended by the manufacturer.NOTE 5For specimen clamping arrangements where the specimen isnot gripped on either end (for example, free bending between knife edges)the spe
36、cimen must be rigid enough at the test start temperature to sustaininitial loading. Alternatively, the calibration specimen, without encapsu-lation, can be placed between the knife edge and a substrate.10.5 Maximum strain amplitude should be within the linearviscoelastic range of the specimens to be
37、 subsequently ana-lyzed. Strains of less than 1 % are recommended and shouldnot exceed 3 %.10.6 Conduct the calibration runs at the heating rate ofinterest, preferably 1 C/min but no greater than 5 C/min anda frequency of 1 Hz. Other heating rates and frequencies maybe used but shall be reported. (S
38、ee Appendix X2.)NOTE 6Calibration for temperature should always be performedunder the conditions of heating rate and frequency at which the unknownspecimens will be tested. This method does not address the issues offrequency affects for polymeric transitions (such as the upwards shift ofglass transi
39、tion temperature with increasing frequency), and will onlycompensate for thermal lag within the measuring device.10.7 Measure and record the ordinate signal, from 30 Cbelow to 20 C above the melting point of the referencematerial. The calibration specimen may be equilibrated aminimum of 50 C below t
40、he melting transition, but adequatetime to achieve thermal equilibrium in the specimen must beallowed.11. Calculation11.1 Take the transition temperature as the extrapolatedonset to the sigmoidal change in the ordinate signal observed inthe downward direction (see Fig. 1).11.1.1 Construct a tangent
41、to the ordinate signal curvebelow the transition temperature.11.1.2 Construct a tangent to the ordinate signal curve at theinflection point approximately midway through the sigmoidalchange associated with the transition.11.1.3 Report the temperature at which these tangent linesintersect as reported
42、as the observed transition temperature(To).11.2 Two Point Calibration:11.2.1 Using the standard temperature values from Table 2and the corresponding onset temperatures obtained experimen-tally, calculate the slope and intercept using the followingequations:S 5 Tr1Tr2/To1To2 (2)I 5 To1 3 Tr2Tr13 To2!
43、# /To1To2 (3)whereS = slope (nominal value = 1.0000),I = intercept,Tr1 = reference transition temperature for Standard 1 (inTable 2),Tr2 = reference transition temperature for Standard 2 (inTable 2),To1 = experimentally observed transition onset tempera-tures for Standard 1, andTo2 = experimentally
44、observed transition onset temperaturefor Standard 2.NOTE 7The slope S is a dimensionless number whose value isFIG. 1 Transition TemperatureE1867 113independent of which temperature scale is used for I and T. I, in all cases,must have the same units as Tr1, Tr2, To1, and To2 that are, by necessity,co
45、nsistent with each other.11.2.2 S should be calculated to 60.0001 units while Ishould be calculated to 60.1 C.11.2.3 Using the determined values for S and I, Eq 1 may beused to calculate the actual specimen transition temperature(Tt) from any experimentally observed transition temperature(To) for th
46、e particular DMA instrument employed.11.3 One Point Calibration:11.3.1 In this abbreviated procedure, a relationship betweenthe extrapolated onset temperature as observed and the tem-perature as assigned by a temperature sensor is established. Theoperator should choose a calibration standard that is
47、 near thetemperature of the transition or phenomenon under study.11.3.2 Using the specimen handling techniques in 10.2through 10.7, obtain the DMA curve for the calibrationstandard chosen from Table 2.11.3.3 From the known melting temperature of the calibra-tion material (see Table 2), calculate the
48、 value and sign of sfrom the following equation:s5Tr To(4)whereTr= reference transition temperature for standard (in Table2),To= experimentally observed transition onset temperaturefor standard, ands = correction factor for converting the observed tempera-ture sensor temperature to actual sample tem
49、perature.11.3.4 For the purpose of this abbreviated procedure, it isassumed that the relationship between the observed extrapo-lated onset temperature (To) and the actual specimen tempera-ture is constant over the temperature range of interest. Thevalue of s is thus added to all observed measurements oftransition temperatures for the particular instrument employed.That is:Tt5 To1s (5)whereTt= temperature of transition to be assigned.12. Report12.1 Report the following information:12.1.1 Description of the instrument (manufacturer
