1、Designation: E1867 13Standard 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 150C to300C.1.2 The values state
3、d in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.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
4、health practices and determine the applica-bility of regulatory 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 Properti
5、esE2161 Terminology Relating to Performance Validation inThermal 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
6、of Test Method4.1 An equation is developed for the linear 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
7、 withpolymer tape and subjecting it to a mechanical oscillation 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 c
8、alibration withtwo melting point reference materials.5. Significance 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
9、 thetemperature of the transition (or event) under study. 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 increas
10、e or decrease in heating rates or change inpurge gas type 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
11、 way that would impede movement. If thetemperature sensor 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 t
12、he specimen testing geometrydiffers significantly from that 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 ap
13、paratus is to hold a specimen ofuniform dimension so that 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 Commit
14、tee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.10 onFundamental, Statistical and Mechanical Properties.Current edition approved April 1, 2013. Published May 2013. Originallyapproved in 1997. Last previous edition approved in 2012 as E1867 12. DOI:10.1520/E1867-13
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.Copyright ASTM International, 100 Barr Harbor Drive, PO Box
16、C700, West Conshohocken, PA 19428-2959. United States17.1.1 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 en
17、d (for example, free bending betweenknife edges).7.1.1.2 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,
18、as in forced vibration devices.7.1.1.3 DetectorA device 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 60.1C,force to 61 % and frequency to 61
19、7.1.1.4 Temperature Controller and OvenA device 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
20、 0.1C.7.1.1.5 A Data Collection Device, to provide a means ofacquiring, storing, and displaying measured or calculatedsignals, or both. The minimum output signals required fordynamic mechanical analysis are storage modulus, lossmodulus, tangent delta, temperature, and time.NOTE 1Some instruments, su
21、itable for this test, may display onlylinear or logarithmic storage modulus while others may display linear orlogarithmic storage modulus, or both. 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 H
22、igh Temperature Polymer Tubing such as PTFE (Poly-tetrafluoroethylene) or PEEK (Polyetheretherketone), of 3-mmoutside diameter and wall thickness of 0.5-mm (0.002 in.)3may be used for low temperature standards (that is, less than160C). The tubing may be sealed with suitable meltingtemperature wax pl
23、ugs, or similar sealant. (See Appendix X3.)NOTE 2PTFE 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.
24、 PEEK provides increasedstiffness for ease of loading. 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 m
25、ore suitable materialspresented in Table 2.7.6 Calipers 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
26、 ice formation is avoided when measurementsinvolve temperatures below the dew point.9. Calibration and Standardization9.1 Prepare the instrument for operation as described by themanufacturer in the operations manual10. Procedure10.1 Two Point CalibrationFor the purposes of thisprocedure, it is assum
27、ed that the relationship between observedextrapolated onset temperature (To) and actual specimen tem-perature (Tt) is a linear one governed by the equation:Tt5 To3 S!1I (1)where: S and I are the slope and intercept of a straight line,respectively.10.2 Select two calibration standards near the temper
28、aturerange of interest. The standards should be as 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
29、polymer test specimens. In some testing geometries 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 exceed1
30、00C. (See Appendix X3.)10.2.1.1 Fill the polymer tubing with the calibration mate-rial or wrap a solid calibrant with PTFE tape. Calibrant mustextend to the ends of the clamping geometry and must haveuniform dimensions with respect to width.3Lotti, C., and Canevarolo, S.V., “Temperature Calibration
31、of a Dynamic-Mechanical Thermal Analyzer,” Polymer Testing, Vol 17, 1998, pp. 523530.TABLE 1 Dynamic Mechanical Analyzer Modes of OperationModeMechanical ResponseTension Flexural Torsion CompressionFree/decA. . X .Forced/res/CAA. X X .Forced/fix/CAAXX XForced/fix/CSAX X . XAFree = free oscillation;
32、dec = decaying amplitude; forced = forced oscillation;CA = constant amplitude; res = resonant frequency; fix = fixed frequency;CS = controlled stress.TABLE 2 Calibration MaterialsMaterialTransition TemperatureAReferenceC KCyclopentane (solid-solid) 151.16 121.99 X1.1Cyclopentane (solid-solid) 135.06
33、 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 X1.4Cyclohexane 6.54 279.69 X1.3Indium 156.5985 495.7485 X1.4Tin 231.928 505.078 X1.4AThe values in this table were determined under spe
34、cial, highly accurate testconditions that are not attainable or applicable to this test method. The actualprecision of this test method is given in Section 13.E1867 132NOTE 4For solid calibrants, a wire of dimensions suitable for testingshould be used.10.3 Measure the length and for solid calibrants
35、 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 specimen must be rigid enough at the
36、 test start temperature to sustaininitial loading. Alternatively, the calibration specimen, withoutencapsulation, 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 subsequently ana-lyzed. Strains of
37、 less than 1 % are recommended and shouldnot exceed 3 %.10.6 Conduct the calibration runs at the heating rate ofinterest, preferably 1C/min but no greater than 5C/min and afrequency of 1 Hz. Other heating rates and frequencies may beused but shall be reported. (See Appendix X2.)NOTE 6Calibration for
38、 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 transition temperature with increasing freq
39、uency), and will onlycompensate for thermal lag within the measuring device.10.7 Measure and record the ordinate signal, from 30Cbelow to 20C above the melting point of the referencematerial. The calibration specimen may be equilibrated aminimum of 50C below the melting transition, but adequatetime
40、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 to the ordinate signal curvebelow the tr
41、ansition 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 as the observed transition temperature(T
42、o).11.2 Two Point Calibration:11.2.1 Using the standard temperature values from Table 2and the corresponding onset temperatures obtainedexperimentally, calculate the slope and intercept using thefollowing equations:S 5 Tr1 2 Tr2#/To1 2 To2# (2)I 5 To1 3 Tr2 2 Tr1 3 To2!#/To1 2 To2# (3)whereS = slope
43、 (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 observed transition onset t
44、emperaturefor Standard 2.FIG. 1 Transition TemperatureE1867 133NOTE 7The slope S is a dimensionless number whose value isindependent 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,consistent with each other.11
45、2.2 S should be calculated to 60.0001 units while Ishould be calculated to 60.1C.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 the particular DMA instrument
46、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 near thetemperature of the
47、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 value and sign of from the
48、following equation: 5 Tr2 To(4)whereTr= reference transition temperature for standard (in Table2),To= experimentally observed transition onset temperaturefor standard, and = correction factor for converting the observed tempera-ture sensor temperature to actual sample temperature.11.3.4 For the purp
49、ose 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 is thus added to all observed measurements oftransition temperatures for the particular instrument employed.That is:Tt5 To1 (5)whereTt= temperature of transition to be assigned.12. Report12.1 Report the following information:12.1.1 Description of the instrument (manufacturer andmodel number) as well as the
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