1、Designation: E1867 11 E1867 12Standard 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 la
2、st revision. 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 calibration of dynamic mechanical analyzers (DMA) from 150 C to 500 C.1.2 The
3、 values stated in SI units are to be regarded as standard.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicabili
4、ty of regulatorylimitations prior to use. Specific precautionary statements are given in Note 7.2. Referenced Documents2.1 ASTM Standards:2E473 Terminology Relating to Thermal Analysis and RheologyE1142 Terminology Relating to Thermophysical PropertiesE2161 Terminology Relating to Performance Valida
5、tion in Thermal Analysis3. Terminology3.1 Definitions:3.1.1 The technical terms used in this test method are defined in Terminologies E473, E1142, and E2161, including dynamicmechanical analysis, frequency, stress, strain and storage modulus.4. Summary of Test Method4.1 An equation is developed for
6、the linear correlation of experimentally observed program or sensor temperature and the actualmelting temperature for known melting reference materials. This is accomplished by loading melting point reference materials intoa polymer tube, or wrapping them with polymer tape and subjecting it to a mec
7、hanical oscillation at either fixed or resonantfrequency. The extrapolated onset of melting is identified by a rapid decrease in the ordinate signal (the apparent storage modulus,stress, inverse strain or probe position). This onset is used for temperature calibration with two melting point referenc
8、e materials.5. Significance and Use5.1 Dynamic mechanical analyzers monitor changes in the viscoelastic properties of a material as a function of temperature andfrequency, providing a means to quantify these changes. In most cases, the value to be assigned is the temperature of the transition(or eve
9、nt) under study. Therefore, the temperature axis (abscissa) of all DMA thermal curves must be accurately calibrated byadjusting the apparent temperature scale to match the actual temperature over the temperature range of interest.6. Interferences6.1 An increase or decrease in heating rates or change
10、 in purge gas type or rate from those specified may alter results.6.2 Once the temperature calibration procedure has been executed, the measuring temperature sensor position shall not bechanged, nor shall it be in contact with the specimen or specimen holder in a way that would impede movement. If t
11、he temperaturesensor position is changed or is replaced, then the entire calibration procedure shall be repeated.1 This test method is under the jurisdiction of ASTM Committee E37 on Thermal Measurements and is the direct responsibility of Subcommittee E37.10 on Fundamental,Statistical and Mechanica
12、l Properties.Current edition approved Aug. 1, 2011Sept. 1, 2012. Published September 2011October 2012. Originally approved in 1997. Last previous edition approved in 20062011as E1867 06.E1867 11. DOI: 10.1520/E1867-11.10.1520/E1867-12.2 For referenced ASTM standards, visit the ASTM website, www.astm
13、.org, or contact ASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what ch
14、anges have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the off
15、icial document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.3 Once the temperature calibration has been executed, the geometry deformation (bending study, versus tensile, and the like)shall not be changed. If the specimen testing
16、 geometry differs significantly from that of the calibrants, then the calibration shallbe repeated in the geometry matching that of specimen testing.6.4 This method does not apply to calibration for shear or compressive geometries of deformation.7. Apparatus7.1 The function of the apparatus is to ho
17、ld a specimen of uniform dimension so that the specimen acts as the elastic anddissipative element in a mechanically oscillated system. Dynamic mechanic analyzers typically operate in one of several modesas outlined in Table 1.7.1.1 The apparatus shall consist of the following:7.1.1.1 ClampsA clampi
18、ng arrangement that permits gripping of the specimen. This may be accomplished by clamping at bothends (most systems), one end (for example, torsional pendulum) or neither end (for example, free bending between knife edges).7.1.1.2 Device to Apply Oscillatory Stress or StrainA device for applying an
19、 oscillatory deformation (strain) or oscillatorystress to the specimen. The deformation may be applied and then released, as in freely vibrating devices, or continually applied,as in forced vibration devices.7.1.1.3 DetectorA device or devices for determining the dependent and independent experiment
20、al parameters, such as force(stress), deformation (strain), frequency, and temperature. Temperature shall be measurable with an accuracy of 60.1 C, force to61 % and frequency to 61 %.7.1.1.4 Temperature Controller and OvenA device for controlling the specimen temperature, either by heating, cooling
21、(insteps or ramps), or by maintaining a constant experimental environment. The temperature programmer shall be sufficiently stableto permit measurement of specimen temperature to 0.1 C.7.1.1.5 A Data Collection Device, to provide a means of acquiring, storing, and displaying measured or calculated s
22、ignals, orboth. The minimum output signals required for dynamic mechanical analysis are storage modulus, loss modulus, tangent delta,temperature, and time.NOTE 1Some instruments, suitable for this test, may display only linear or logarithmic storage modulus while others may display linear and/orloga
23、rithmic storage modulus. Care must be taken to use the same modulus scale when comparing unknown specimens, and in the comparison of resultsfrom one instrument to another.7.2 High Temperature Polymer Tubing such as PTFE (Polytetrafluoroethylene) or PEEK (Polyetheretherketone), of 3-mmoutside diamete
24、r and wall thickness of 0.5-mm (0.002 in.)3 inner diameter may be used for low temperature standards (that is, lessthan 160 C). The tubing may be sealed with suitable melting temperature wax plugs, or similar sealant.NOTE 2PTFE tubing is selected for its flexibility and inert nature for the solvents
25、 in use at the temperatures of interest. Furthermore its transitionsshould not produce any interference in the DMA signal within the range of the suggested calibrant materials. PEEK provides increased stiffness for easeof loading. For other temperature ranges, a suitable replacement for the high tem
26、perature 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 materials presented in Table 2.7.6 Calipers or other length measuring device capable of measuring dimensions (
27、or length) within 610 m.8. Reagents and Materials8.1 Dry nitrogen, helium, or other inert gas supplied for purging purposes and especially to ensure that moisture condensationand ice formation is avoided when measurements involve temperatures below the dew point.3 Lotti, C., and Canevarolo.Canevarol
28、o, S.V., “Temperature Calibration of a Dynamic Mechanical Dynamic-Mechanical Thermal Analyzer,” Polymer Testing, Vol 17, 1998,pp. 523530.TABLE 1 Dynamic Mechanical Analyzer Modes of OperationMode Mechanical ResponseTension Flexural Torsion CompressionFree/decA . . . . . . X . . .Forced/res/CAA . . .
29、 X X . . .Forced/fix/CAA X X X XForced/fix/CSA X X . . . XA Free = free oscillation; dec = decaying amplitude; forced = forced oscillation;CA = constant amplitude; res = resonant frequency; fix = fixed frequency;CS = controlled stress.E1867 1229. Calibration and Standardization9.1 Prepare the instru
30、ment for operation as dexcribed by the manufacturer in the operations manual10. Procedure10.1 Two Point CalibrationFor the purposes of this procedure, it is assumed that the relationship between observedextrapolated onset temperature (To) and actual specimen temperature (Tt) is a linear one governed
31、 by the equation:Tt 5To 3S!1I (1)where: S and I are the slope and intercept of a straight line, respectively.10.2 Select two calibration standards near the temperature range of interest. The standards should be as close to the upper andlower temperature limits used for the subsequent test materials
32、as practical.NOTE 3The purpose of the polymer encapsulation is to provide thermal resistance between the test specimen and the environment similar to thatoffered by polymer test specimens. In some testing geometries it may be possible to perform the test directly on the metal melting point reference
33、 materialswithout encapsulation. (See Appendix X2.)10.2.1 Encapsulation technique for low temperature (liquid) standards where the melting temperature does not exceed 100 C.10.2.1.1 Fill the polymer tubing with the calibration material or wrap a solid calibrant with PTFE tape. Calibrant must extendt
34、o the ends of the clamping geometry and must have uniform dimensions with respect to width.NOTE 4For solid calibrants, a wire of dimensions suitable for testing should be used.10.3 Measure the length and for solid calibrants the diameter as well, of specimens.10.4 Mount the specimen in accordance wi
35、th the procedure recommended by the manufacturer.NOTE 5For specimen clamping arrangements where the specimen is not gripped on either end (for example, free bending between knife edges) thespecimen must be rigid enough at the test start temperature to sustain initial loading. Alternatively, the cali
36、bration specimen, without encapsulation, canbe placed between the knife edge and a substrate.10.5 Maximum strain amplitude should be within the linear viscoelastic range of the specimens to be subsequently analyzed.Strains of less than 1 % are recommended and should not exceed 3 %.10.6 Conduct the c
37、alibration runs at the heating rate of interest, preferably 1 C/min but no greater than 5 C/min and afrequency of 1 Hz. Other heating rates and frequencies may be used but shall be reported. (See Appendix X2.)NOTE 6Calibration for temperature should always be performed under the conditions of heatin
38、g rate and frequency at which the unknown specimenswill be tested. This method does not address the issues of frequency affects for polymeric transitions (such as the upwards shift of glass transitiontemperature with increasing frequency), and will only compensate for thermal lag within the measurin
39、g device.10.7 Measure and record the ordinate signal, from 30 C below to 20 C above the melting point of the reference material. Thecalibration specimen may be equilibrated a minimum of 50 C below the melting transition, but adequate time to achieve thermalequilibrium in the specimen must be allowed
40、.11. Calculation11.1 Take the transition temperature as the extrapolated onset to the sigmoidal change in the ordinate signal observed in thedownward direction (see Fig. 1).TABLE 2 Calibration MaterialsMaterial Transition TemperatureAReferenceC KCyclopentane (solid-solid) 151.16 121.99 X1.1Cyclopent
41、ane (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 X1.4Cyclohexane 6.54 279.69 X1.3Indium 156.5985 495.7485 X1.4Tin 231.928 505.078 X1.4Lead 327.462 600.612 X1.5Zi
42、ncB 419.527 692.677 X1.4A The values in this table were determined under special, highly accurate testconditions that are not attainable or applicable to this test method. The actualprecision of this test method is given in Section 13.B Amalgamates with aluminum. Do not heat above 430 C.E1867 12311.
43、1.1 Construct a tangent to the ordinate signal curve below the transition temperature.11.1.2 Construct a tangent to the ordinate signal curve at the inflection point approximately midway through the sigmoidalchange associated with the transition.11.1.3 Report the temperature at which these tangent l
44、ines intersect as reported as the observed transition temperature (To).11.2 Two Point Calibration:11.2.1 Using the standard temperature values from Table 2 and the corresponding onset temperatures obtained experimentally,calculate the slope and intercept using the following equations:S 5Tr12Tr2#/To1
45、2To2# (2)I 5To13Tr22Tr13To2!#/To12To2# (3)whereS = slope (nominal value = 1.0000),I = intercept,Tr1 = reference transition temperature for Standard 1 (in Table 2),Tr2 = reference transition temperature for Standard 2 (in Table 2),To1 = experimentally observed transition onset temperatures for Standa
46、rd 1, andTo2 = experimentally observed transition onset temperature for Standard 2.NOTE 7The slope S is a dimensionless number whose value is independent of which temperature scale is used for I and T.I, in all cases, must havethe same units as Tr1, Tr2, To1, and To2 that are, by necessity, consiste
47、nt with each other.11.2.2 S should be calculated to 60.0001 units while I should be calculated to 60.1 C.11.2.3 Using the determined values for S and I,Eq 1 may be used to calculate the actual specimen transition temperature (Tt)from any experimentally observed transition temperature (To) for the pa
48、rticular DMA instrument employed.11.3 One Point Calibration:11.3.1 In this abbreviated procedure, a relationship between the extrapolated onset temperature as observed and the temperatureas assigned by a temperature sensor is established. The operator should choose a calibration standard that is nea
49、r the temperatureof the transition or phenomenon under study.11.3.2 Using the specimen handling techniques in 10.2 through 10.7, obtain the DMA curve for the calibration standard chosenfrom Table 2.11.3.3 From the known melting temperature of the calibration material (see Table 2), calculate the value and sign of from thefollowing equation:5Tr 2To (4)FIG. 1 Transition TemperatureE1867 124whereTr = reference transition temperature for standard (in Table 2),To = experimentally observed transition onset temperature for standard, an
