1、Designation: E 1363 08Standard Test Method forTemperature Calibration of Thermomechanical Analyzers1This standard is issued under the fixed designation E 1363; 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 thermomechanical analyzers from 50 to 1100 C. (SeeNote 1.)1.2 The values
3、 stated in SI units are to be regarded asstandard. No other units of measurement are included in thisstandard.1.3 This standard is similar to ISO 113591 but addresses alarger temperature range and utilizes additional calibrationmaterials.1.4 This standard does not purport to address all of thesafety
4、 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 regulatory limitations prior to use. Specific precau-tionary statements are given in Section 7 and Note 9.2. Refe
5、renced Documents2.1 ASTM Standards:2E 473 Terminology Relating to Thermal Analysis and Rhe-ology2.2 Other Standards:113591 Thermomechanical Analysis (TMA)-Part 1: Gen-eral Principles33. Terminology3.1 Definitions:3.1.1 The terminology relating to thermal analysis appear-ing in E 473 shall be conside
6、red applicable to this document.4. Summary of Test Method4.1 An equation is developed for the linear correlation of theexperimentally observed program temperature and the actualmelting temperature for known melting standards. This isaccomplished through the use of a thermomechanical analyzerwith a p
7、enetration probe to obtain the onset temperatures fortwo melting point standards.An alternate, one-point method oftemperature calibration, is also given for use over very narrowtemperature ranges. (See Note 2.)NOTE 1This test method may be used for calibrating thermomechani-cal analyzers at temperat
8、ures outside this range of temperature. However,the accuracy of the calibration will be no better than that of thetemperature standards used.NOTE 2It is possible to develop a more elaborate method of tempera-ture calibration using multiple (more than two) fusion standards andquadratic regression ana
9、lysis. Since most modern instruments are capableof heating rates which are essentially linear in the region of use, theprocedure given here is limited to a two-point calibration.5. Significance and Use5.1 Thermomechanical analyzers are employed in theirvarious modes of operation (penetration, expans
10、ion, flexure,etc.) to characterize a wide range of materials. In most cases,the value to be assigned in thermomechanical measurements isthe temperature of the transition (or event) under study.Therefore, the temperature axis (abscissa) of all TMA thermalcurves must be accurately calibrated either by
11、 direct reading ofa temperature sensor or by adjusting the programmer tempera-ture to match the actual temperature over the temperature rangeof interest.6. Apparatus6.1 Thermomechanical Analyzer (TMA), The essential in-strumentation required to provide the minimum thermome-chanical analytical or the
12、rmodilatometric capability for thismethod includes:1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.01 on ThermalTest Methods and Practices.Current edition approved Sept. 1, 2008. Published September 2008. Or
13、iginallyapproved in 1990. Last previous edition approved in 2003 as E 1363 03.2For 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 on
14、the ASTM website.3Available from American National Standards Institute, 11 W. 42nd St., 13thFloor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.1.1 A Rigid Specimen Holder or Platform, of inert, lowexpansivity
15、 material ( 1 m m-1K-1) to center the specimen inthe furnace and to fix the specimen to mechanical ground.6.1.2 A Rigid (expansion compression, flexure, tensile, etc)Probe, of inert, low expansivity material ( 1 m m-1K-1) thatcontacts with the specimen with an applied compressive ortensile force. Fo
16、r this test method the use of a penetration probeis recommended.6.1.3 A Sensing Elementlinear over a minimum range of2 mm to measure the displacement of the rigid probe to 6 50nm resulting from changes in the length/height of the speci-men.6.1.4 A Weight or Force Transducer, to generate a constantfo
17、rce of 50 6 5 mN (5.0 6 0.5 g) that is applied through therigid probe to the specimen.NOTE 3The recommendation of a 5.0 g load (or a force of 50 mN) isbased on the use of penetration probes commonly used in the commer-cially available thermomechanical analyzers. These probes have tipdiameters rangin
18、g from 0.89 to 2.0 mm and lead to pressures from 80 to16 kPa when using the recommended 5.0 g load. The use of probes whichdiffer greatly from this range of tip diameters may require differentloading (or force).6.1.5 A Furnace, capable of providing uniform controlledheating (cooling) at a rate of 10
19、 6 1 C min-1of a specimen toa constant temperature within the applicable temperature rangeof this methodNOTE 4The temperature range of operation of commercial thermo-mechanical analyzers vary by manufacturer and mode. The completerange of temperature of an instrument is sometimes achieved by the use
20、 oftwo different furnaces. In this case, temperature calibration must becarried out for each furnace.6.1.6 A Temperature Controller, capable of executing aspecific temperature program by operating the furnace betweenselected temperature limits at a rate of temperature change of10 6 1 C min-1.6.1.7 A
21、 Temperature Sensor, that may be positioned in closeproximity to the test specimen to provide an indication of thespecimen/furnace temperature to within 6 0.1 C min6.1.8 A means of sustaining an environment around thespecimen with an inert purge gas (e.g., nitrogen, helium, argon,etc.) at a purge ga
22、s flow rate of 20 to 50 mL min-1.6.1.9 A Data Collection Device, to provide a means ofacquiring, storing, and displaying measured or calculatedsignals, or both. The minimum output signals required forTMAare a change in linear dimension, temperature, and times.7. Hazards7.1 This test method may invol
23、ve the use of hazardousmaterials, operations, and equipment. It is the responsibility ofthe user of this test method to establish appropriate safetypractice and to determine the applicability of regulatorylimitations prior to use.NOTE 5Warning: Toxic or corrosive effluents, or both, may bereleased w
24、hen heating some materials and could be harmful to personneland the apparatus.7.2 Once this calibration procedure has been executed asdescribed in 10.1.2.1-10.1.2.7 of this test method, the measur-ing temperature sensor position should not be changed, norshould it be in contact with the sample or sa
25、mple holder in away that would impede movement. If for some reason thetemperature sensor position is changed or the temperaturesensor is replaced, then the entire calibration procedure shouldbe repeated.8. Calibration8.1 For the temperature range covered by many applica-tions, the melting transition
26、 of 99.99 % pure materials may beused for calibration. (See Table 1.)NOTE 6The melting temperatures of these materials have beenselected as primary fixed points (see Table 1) for the InternationalPractical Temperature Scale of 1990.4NOTE 7Some materials have different crystalline forms (for example,
27、tin) or may react with the container. Such calibration materials should bediscarded after their initial melt.9. Assignment of the Penetration Onset Temperature9.1 The assignment of the TMA penetration onset tempera-ture is an important procedure since, when using this method,temperature calibration
28、of the thermomechanical analyzer isdirectly dependent upon it. The temperature standards given inTable 1 will give a downward deflection on the thermal curve,similar to that shown in Fig. 1, when placed under a weightedTMA penetration probe and heated to their respective meltingtemperatures.9.2 The
29、extrapolated onset temperature for such a penetra-tion thermal curve is obtained by extending the pretransitionportion of the thermal curve to the point of intersection with aline drawn tangent to the steepest portion of the curve whichdescribes the probe displacement. The temperature correspond-ing
30、 to this point of intersection is the penetration onsettemperature. This is shown graphically in Fig. 1. There aresome materials (for example, aluminum metal) which showpretransition probe displacement prior to the sharper down-ward deflection observed on melting. In this case, the pretran-sition ba
31、seline is extended from the point which represents thehighest temperature the material reaches prior to exhibiting4Supporting data have been filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR: E371011.TABLE 1 Recommended Melting Temperature StandardsACalibra
32、tion MaterialBMelting Temperature(C) (K)Mercury 38.8344 234.3156Water 0.01 273.16Gallium 29.7646 302.9146Indium 156.5985 429.7485Tin 231.928 505.078Zinc 419.527 692.677Aluminum 660.323 933.473Silver 961.78 1234.93Gold 1064.18 1337.33Copper 1084.62 1357.77AThe values in Table 1 were determined using
33、special, 99.9999 % purematerials, and highly accurate steady state conditions that are not attainable orapplicable to thermal analysis techniques. The actual precision of this test methodis given in Section 12.BB. W. Mangnum and G. T. Furukawa, “Guidelines for Realizing the Interna-tional Temperatur
34、e Scale of 1990 (ITS-90),” National Institute of Standards andTechnology Technical Note 1265, page 8, 1990.E1363082significant or measurable softening under the conditions of theexperiment. Fig. 2 describes the assignment of the extrapolatedonset temperature for a specimen which exhibits pretransiti
35、onpenetration.10. Procedure10.1 Two-Point CalibrationFor the purposes of this pro-cedure, it is assumed 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! 1 I (1)where: S and I are the sl
36、ope and intercept of a straight line,respectively.10.1.1 Select two calibration standards near the temperaturerange of interest. The standards should be as close to the upperand lower temperature limits used in the actual analysis runs asis practical.10.1.2 Determine the apparent extrapolated onset
37、tempera-ture for the calibration material chosen, using a penetration-type probe with the TMA instrument.10.1.2.1 Place a 10 to 20-mg specimen of one of thecalibration standards on the sample platform (or holder, which-ever is applicable).The specimen should have a smooth surfaceon both top and bott
38、om.Avoid the use of specimens with sharpridges and irregular surfaces. These can lead to false values forthe onset temperatures. Powdered or liquid standards may beplaced into a stable, inert container, if necessary.10.1.2.2 Place a probe loaded with 5 g (or force of 50 mN)in contact with the test s
39、pecimen.10.1.2.3 Purge the sample chamber area with inert gas at aflow rate that is appropriate to the dimensions of the apparatusthroughout the experiment. Typical flow rates are from 20 to 50mL/min. The same purge gas and flow rate should be main-tained in both calibration runs and analyses runs.1
40、0.1.2.4 Heat the calibration sample specimen to a tempera-ture about 50 C below the calibration temperature and allowthe TMA furnace to equilibrate.10.1.2.5 Heat the calibration specimen through the transi-tion allowing the probe to reach a point of maximum penetra-tion. (See Fig. 1.)NOTE 8Temperatu
41、re calibration may be affected by heating rate,purge gas flow rate, and choice of purge gas.10.1.2.6 From the TMA thermal curve obtained, assign theextrapolated onset temperature (see Fig. 1) to the requiredprecision.NOTE 9Retain all available digits.10.1.2.7 Repeat the procedure described in 10.1.2
42、-10.1.2.5using the second calibration standard that was chosen.11. Calculation11.1 Using the standard temperature values from Table 1and the corresponding onset temperatures obtained experimen-tally, calculate the slope and intercept using the followingequations:S 5 Ta12 Ta2/T012 T02 (2)I 5 T013 Ta2
43、! 2 Ta13 T02!#/T012 T02! (3)where:S = slope (nominal value = 1.00),I = intercept,Ta1= reference transition temperature for Standard 1 takenfrom Table 1,Ta2= reference transition temperature for Standard 2 takenfrom Table 1,T01= experimentally observed transition onset tempera-ture for Standard 1, an
44、dT02= experimentally observed transition onset tempera-ture for Standard 2.NOTE 10Caution: The slope S is a dimensionless number whosevalue is independent of which temperature scale is used for I and T. I,inall cases, must have the same units as Ta1, Ta2, T01and T02that are bynecessity consistent wi
45、th each other.11.2 S should be calculated to 60.01 units while I shouldbe calculated to 60.1 C.11.3 Using the determined values for S and I, Eq 1 may beused to calculate the actual specimen transition, Tt, from anyexperimentally observed transition temperature, T0, for theparticular TMA instrument e
46、mployed.NOTE 11The final result is rounded to the nearest 0.1 C consistentFIG. 1 Assignment of the Extrapolated Onset Temperature (To)from TMA Thermal CurveFIG. 2 Assignment of Extrapolated Onset Temperature (To) fromTMA Thermal Curve for Specimen Exhibiting PretransitionSofteningE1363083with the re
47、peatability standard deviation reported in 13.2.1.11.4 One-Point Calibration:11.4.1 In this abbreviated procedure, a relationship betweenthe extrapolated onset temperature as observed from the use ofa weighted penetration probe with one of the metal calibrationstandards (see Table 1) and the tempera
48、ture as assigned by atemperature sensor is established. The operator should choosea calibration standard that is near the temperature of thetransition or phenomenon under study. For example, if onewere interested in assigning the glass transition temperature ofa polycarbonate specimen (Tg 150 C), a
49、good choice for thetemperature calibration standard would be indium metal (Tm= 156.6 C). Provision is made in this procedure so that theX-axis of the thermal curve is either a direct or indirect measure(that is, numerically assigned by) of the voltage output of atemperature sensor.11.4.1.1 Using the sample handling techniques as describedin 7.1 and 10.1.2, use a penetration probe to obtain the TMAthermal curves for the calibration standard chosen in Table 1.11.4.1.2 From the known melting point of the calibrationmaterial (see Table 1), calcu
