1、Designation: E 2509 08Standard Test Method forTemperature Calibration of Rheometers in Isothermal Mode1This standard is issued under the fixed designation E 2509; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last rev
2、ision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This test method describes the temperature calibrationor conformance of rheometers. The applicable temperaturerange is 0 to 8
3、0 C however other ranges may be selected for thepurpose at hand.1.2 SI units are the standard.1.3 There are no ISO equivalents to this standard.1.4 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 standa
4、rd to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E 473 Terminology Relating to Thermal Analysis and Rhe-ologyE 1142 Terminology Relating to Thermophysical Properties3. Terminolo
5、gy3.1 Specific technical terms found in this standard aredefined in Terminologies E 473 and E 1142 including rheom-eter and rheometry4. Summary of Test Method4.1 An electronic thermometer of known characteristics isplaced in the center of a dummy test specimen in contact withthe torque applying inst
6、rument plates of a rheometer atconstant (isothermal) temperature. The difference between therheometer set temperature and that indicated by the thermom-eter is used to calibrate the rheometer temperature signal.5. Significance and Use5.1 Rheological properties such as viscosity and storage andloss m
7、odulus change rapidly with temperature. High qualitydeterminations of these properties depend upon a stable andwell-known temperature of the measuring apparatus.6. Interferences6.1 In many rheological experiments, temperature is variedwith time. The calibration in this method is made under stableand
8、 isothermal temperature conditions. Thus the effects ofchanges in temperature with time are not addressed. Thisisothermal calibration does not provide any information aboutthe specimen under temperature scanning conditions.7. Apparatus7.1 An Electronic Thermometer that includes:7.1.1 Temperature Sen
9、sor, (such as a thermocouple, plati-num resistance thermometer, thermistor, etc.) with an accuracy(traceable to a known absolute standard) and resolution of 60.1 C and a range of 0 to 80 C.NOTE 1Sensors with other temperature ranges may be used at theoperators convenience.NOTE 2Some sensors are avai
10、lable already affixed with dummy testspecimens from section 7.27.1.2 Temperature indicator , to convert the signal presentedby the temperature sensor into a digital electronic temperaturedisplay with the accuracy and precision indicated in section7.1.1.7.2 Dummy Test Specimen, Two polymer sheets eac
11、h 1mmin thickness of such a diameter to fill the space (i.e. gap)between the instrument plates.NOTE 3The dummy test specimen may be composed of the materialto be tested or some other representative polymer material. Polydimeth-ylsiloxane (PDMS) (e.g. “Silly Putty” ) may be used for this purpose.NOTE
12、 4Polydimethylsiloxane may leave a residue of silicone oil onthe surfaces of the instrument plates. This oil should be removed prior tosubsequent use.7.3 Rheometer , The essential instrumentation required pro-viding the minimum rheological analytical capabilities for thismethod include:7.3.1 A drive
13、 actuator, to apply torque or displacement tothe specimen in a periodic manner capable of frequencies ofoscillation from 0.01 to 10 rad/s (0.0016 to 1.6 Hz). Thisactuator may also be capable of providing static force ortransient step or displacement of the test specimen.1This test method is under th
14、e jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.01 on ThermalTest Methods and Practices.Current edition approved Feb. 1, 2008. Published April 2008.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Cus
15、tomer 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 States.7.3.2 Acoupling shaft, or other me
16、ans to transmit the torqueor displacement from the actuator to the specimen.7.3.3 A geometry, tools or plates, to fix the specimenbetween the coupling shaft and a stationary position. For thepurposes of this test, parallel plates are the preferred configu-ration7.3.4 Either a torque sensor, to measu
17、re force developed bythe specimen or a position sensor to measure the angulardisplacement , either one being capable of measuring withinlimits appropriate to the specimen and test being performed.7.3.5 A temperature sensor, to provide an indication of thespecimen temperature readable to within 6 0.1
18、 C.7.3.6 A furnace or heating/cooling element , to providecontrolled heating or cooling of a specimen to a constanttemperature constant to within +/- 0.1 C over the temperaturerange of interest.7.3.7 A temperature controller , capable of executing aspecific temperature program by operating the furna
19、ce orheating/cooling element between selected temperature limitsconstant to within 6 0.1 C.7.3.8 A stress or stain controller , capable of executing aspecific unidirectional or oscillatory stress or strain programbetween selected stress or strain limits capable of controllingwithin limits appropriat
20、e to the specimen and test beingperformed.7.3.9 A recording device, capable of recording all signalsand displaying on the Y-axis any subset of the measured signal(such as applied force, position or frequency) or calculatedsignal (such as viscosity, storage modulus, loss modulus ortangent delta) usin
21、g a linear or logarithmic scale as a functionof any subset of the independent experimental parameter (suchas temperature time, stress, strain or frequency of oscillation.)on the X-axis.7.3.10 Auxiliary instrumentation considered necessary oruseful in conducting this method includes:7.3.10.1 A coolin
22、g capability to hasten cool down fromelevated temperatures, to provide constant cooling rates, or tosustain an isothermal subambient temperature.7.3.10.2 Data analysis capability, to provide determinedsignals (such as viscosity, storage or loss modulus) or otheruseful parameters derived from the mea
23、sured signals.8. Preparation of Apparatus8.1 Turn on the rheometer and allow it to equilibrate for atleast 30 minutes prior to temperature calibration.8.2 Assemble the rheometer with the instrument plates to beused during subsequent tests.9. Calibration and Standardization9.1 Perform any temperature
24、 calibration procedures recom-mended by the rheometer manufacturer as described in theinstruments operations manual.10. Procedure10.1 Insert the temperature sensor so that it is located at thevertical and radial center of the dummy test specimen.NOTE 5This may be accomplished by placing the sensor b
25、etween twosheets of the dummy test specimen.10.2 Mount the dummy test specimen between the instru-ment plates. Close the gap to the dimension to be used for thetest specimen, keeping the temperature sensor centered verti-cally and radially.NOTE 6Other gaps and plate diameters may be used but shall b
26、ereported.NOTE 7It is not necessary to trim the dummy test specimen but a largeexcess of material beyond the edges of the plates should be avoided.10.3 Heat (or cool) the plates to the desired calibrationtemperature and equilibrate until the indicated temperaturechanges by less than 6 0.1 C in 5 min
27、.10.4 Measure and record the temperature indicated by thethermometer as Toand that of set temperature of the rheometeras Ts.10.5 Determine the temperature calibration value accordingto section 11.NOTE 8- Depending upon the needs of the user, a single pointtemperature calibration may be adequate. In
28、this case a single offsetcalibration value is determined. Others may prefer a two-point tempera-ture calibration where the temperature values of interest are selected toencompass all test temperatures. Here a linear interpolation of resultsbetween the two temperature calibration points may be used.
29、Some usersmay wish to calibrate the apparatus at temperature intervals over the fullrange of the temperature range. In this case, a working curve composed ofoffset values as a function of temperature should be created.11. Calculation or Interpretation of Results11.1 The temperature response of the a
30、pparatus is assumedto be linear and is described by the equation:To5 STs1 b (1)where:To= observed temperature in C,Ts= requested controller temperature in C,S = Slope of the plot of Tovs. Ts, dimensionless, andb = temperature offset or bias (intercept of the Tovs. Tsplot) in C11.2 Single Point Tempe
31、rature Calibration11.2.1 In a single point calibration, it is assumed that theslope (S) for the instrument calibration is 1.00000 and thatthere is only an offset between the observed and requestedtemperature. This is a reasonable assumption where the tem-perature range to be used is narrow.11.2.2 Th
32、e offset or bias (b) is given by:b 5 ToTs(2)11.2.3 The value for b is determined by entering the valuesfor Toand Tsmeasured according to section 10.4 into Eq 211.2.4 The true value for an instrument requested tempera-ture is then given by:T 5 Ts1 b (3)where:T = true specimen temperature in C11.3 Two
33、 Point Temperature Calibration11.3.1 In a two-point temperature calibration, the responseof the instrument is assumed to be linear and the slope andoffset may be used to describe the relationship between theE2509082requested temperature and that achieved. This is a reasonableassumption over a broad
34、temperature range for well-designedinstruments.11.3.2 The slope (S) of the calibration plot is given by:S5 Tohi! Tolo!#/Tshi! Tslo!# 5DTo/DTs(4)where:To(hi) = High observed temperature in C,To(lo) = Low observed temperature in C,Ts(hi) = High set temperature in C,Ts(lo) = Low set temperature in C.ar
35、e taken from measurements according to section 10.4.11.3.3 The offset (b) is the intercept of the calibration plotand is given by:b 5 $ Tshi! 3 Tolo!# Tslo! 3 Tohi!#%/ Tshi! Tslo!# (5)where:b = Calibration intercept in C.11.3.4 The true temperature for an observed temperaturemeasurement is then give
36、n by:T 5 STs1 b (6)11.4 Multi-Point Temperature Calibration11.4.1 In the multi-point temperature calibration, the re-sponse of the apparatus is considered to be linear over the shortdifference interval between observation points, but non-linearover the large temperature interval of the whole range o
37、f theapparatus.11.4.2 Prepare a Calibration Working Table with threecolumns labeled observed temperature (To), requested control-ler temperature (Ts) and temperature difference (b) where:b 5 ToTs(7)where:To(hi) = High observed temperature in C,To(lo) = Low observed temperature in C,Ts(hi) = High set
38、 temperature in C,Ts(lo) = Low set temperature in C.are taken from measurements according to section 10.411.4.3 Fill in the table with observed values measuredaccording to section 10.4 and calculated offset values fromsection 11.4.211.4.4 The true temperature for a requested temperature isdetermined
39、 by interpolation of the adjacent temperature pointsin the Calibration Working Table and Eq 3 where the value ofb is the offset for the corresponding value of Ts.NOTE 9Alternatively, the results of the Calibration Working Tablemay be plotted with Toon the ordinate (Y-axis) and Tson the abscissa(X-ax
40、is). Moreover, the data may be fitted by a polynomial, cubic splineor other mathematical curve fitting technique to obtain a CalibrationWorking Equation. This equation may be used to determine the truetemperature from an observed temperature measurement.12. Report12.1 Report the following informatio
41、n:12.1.1 Description of the instrument (manufacturer andmodel number) as well as the data-handling device used in thetest.12.1.2 Description of the dimension, geometry, and materialof the dummy test specimen.12.1.3 Method of Calibration: Single Point, two Point orMulti-Point Calibration12.1.4 For th
42、e Single Point Method, the temperature ofcalibration and the value for the bias (b).12.1.5 For the Two Point Calibration, the high and lowcalibration temperatures (known as the calibration temperaturerange) , and the values of calibration slope (S) and intercept (I).12.1.6 For the multipoint tempera
43、ture calibration, the highand low calibration temperatures (known as the calibrationtemperature range) and the Calibration Working Table.12.1.7 The specific dated version of this method used.13. Precision and Bias13.1 The precision and bias of this test method will bedetermined in an interlaboratory
44、 test program schedule for2007-2008. Anyone wishing to participate in the interlabora-tory test should contact the E37 Staff Manager at ASTMInternational Headquarters.13.2 A limited interlaboratory test was conducted in 2007involving two laboratories and 6 replicate determinations. Thewithin laborat
45、ory repeatability standard deviation was 0.16 Cand the between laboratory reproducibility standard deviationwas 0.38 C. The mean bias was found to be 0.28 C.14. Keywords14.1 calibration; rheometer; temperature; thermal analysisASTM International takes no position respecting the validity of any paten
46、t rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination 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 a
47、t any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your commen
48、ts will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that 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
49、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).E2509083
