1、Designation: E2425 11E2425 16Standard Test Method forLoss Modulus Conformance of Dynamic MechanicalAnalyzers1This standard is issued under the fixed designation E2425; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope Scope*1.1 This test method describes the performance confirmation or measurement of conformance for the loss modulus scale o
3、f acommercial or custom-built dynamic mechanical analyzer (DMA) at 21 C21C using ultra-high molecular weight polyethyleneas a reference material.1.2 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.1.3 There is no ISO standard
4、equivalent to this test method.1.4 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 to determine the applicability of regulatorylimitati
5、ons prior to use.2. Referenced Documents2.1 ASTM Standards:2E473 Terminology Relating to Thermal Analysis and RheologyE1142 Terminology Relating to Thermophysical PropertiesE1867 Test Methods for Temperature Calibration of Dynamic Mechanical Analyzers3. Terminology3.1 DefinitionsSpecific technical t
6、erms used in this test method are defined in Terminologies E473 and E1142 includingCelsius, dynamic mechanical analysis, and loss modulus.4. Summary of Test Method4.1 The loss modulus signal measured by a dynamic mechanical analyzer for an elastic material is compared to the reported lossmodulus for
7、 that reference material.Alinear relationship is used to correlate the experimental loss modulus signal with the reportedvalue of the reference material.4.2 The mode of deformation (for example, tensile, flexure, compression, shear.shear, etc.) shall be reported.5. Significance and Use5.1 This test
8、method demonstrates conformity of a dynamic mechanical analyzer at an isothermal temperature of 21 C.21C.5.2 Dynamic mechanical analysis experiments often use linear temperature change. This test method does not address the effectof that change in temperature on the loss modulus.5.3 This test method
9、 may be used in research and development, specification acceptance, and quality control or assurance.6. Apparatus6.1 The essential instrumentation required to provide the minimum dynamic mechanical capability for this test method includes:1 This test method is under the jurisdiction ofASTM Committee
10、 E37 on Thermal Measurements and is the direct responsibility of Subcommittee E37.10 on Fundamental,Statistical and Mechanical Properties.Current edition approved April 1, 2011June 1, 2016. Published May 2011June 2016. Originally approved in 2005. Last previous edition approved in 20052011 asE2425 0
11、5.E2425 11. DOI: 10.1520/E2425-11.10.1520/E2425-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This docum
12、ent is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes 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 a
13、ppropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United
14、States16.1.1 Drive Actuator, to apply force (or displacement) to the specimen in a periodic manner. This actuator may also be capableof providing static force or displacement to the specimen.6.1.2 Coupling Shaft, or other means to transmit the force from the motor to the specimen.6.1.3 Clamping Syst
15、em(s), to fix the specimen between the drive shaft and the stationary clamp(s).6.1.4 Position Sensor, to measure the change in position of the specimen during dynamic motion, or6.1.5 Force Sensor, to measure the force developed by the specimen.6.1.6 Temperature Sensor, to provide an indication of th
16、e specimen temperature to within 61 C.61C.6.1.7 Furnace, to provide controlled heating or cooling of a specimen at a constant temperature or at a constant rate within theapplicable temperature range of 100 to +300 C.+300C.6.1.8 Temperature Controller, capable of executing a specific temperature prog
17、ram by operating the furnace between 100 and+300 C+300C and at a constant temperature within that range.6.1.9 Data Collection Device, to provide a means of acquiring, storing, and displaying measured or calculated signals, or both.The minimum output signals required for dynamic mechanical analysis a
18、re storage modulus, loss modulus, tan delta, temperature,and time.6.2 Auxiliary instrumentation considered necessary in conducting this method near or below ambient temperature:6.2.1 Cooling capability to sustain a constant temperature at or below ambient temperature or to provide controlled cooling
19、.6.2.2 Data Analysis capability to provide loss modulus information derived from measured signals.7. Reagents and Materials7.1 A reference material of known loss modulus, formed to the shape suitable for characterization by the particular dynamicmechanical analyzer (see Table 1).8. Sampling and Test
20、 Specimens8.1 Test specimens are typically prepared in the form of a rectangular test bars or film strips.NOTE 1It is common practice to bevel or “break” edges of machined parts. This practice shall not be followed in the preparation of test specimensfor this method. The measured loss modulus of suc
21、h specimens reads low due to imperfect sample geometry.9. Calibration and Standardization9.1 Perform any loss modulus signal calibration procedure recommended by the manufacturer of the dynamic mechanicalanalyzer as described in the operations manual.9.2 If not already done so, calibrate the tempera
22、ture scale of the dynamic mechanical analyzer as near as is practical to the testtemperature (see Table 1) using Test MethodMethods E1867.10. Procedure10.1 Prepare the dynamic mechanical analyzer for operation under the test conditions (for example, specimen clamps, purgegas, etc.) to be used for th
23、e characterization of the test specimen(s). Unless otherwise indicated the temperature condition shall beisothermal at 21 6 1 C21 6 1C (that is, between 20 and 22 C).22C).10.2 Ensure that the loss modulus signal is less than 1 MPa with no test specimen loaded and at an oscillation test frequencyto b
24、e used in this test (see Table 1).NOTE 2Alternatively, a thin specimen of a low modulus material (for example, a thin piece of paper) may be used. The dimension of the test specimenshall be used rather than the true dimensions of the thin, low modulus material.10.3 Open the apparatus, place the refe
25、rence material into the specimen holder, and reassemble the apparatus. Equilibrate thereference material at the test conditions. conditions for 30 min. Unless otherwise indicated, the test frequency shall be that indicatedin Table 1 and the temperature shall be isothermal between 20 and 22 C.22C. En
26、sure that the applied strain (or stress) amplitudeis within the linear viscoelastic region of the sample.10.4 Record the loss modulus observed by the apparatus as Eo.TABLE 1 Reference Material Loss ModulusATemperature(C)Material FrequencyHzLossModulus(MPa)21 Ultra-High Molecular Weight PolyethyleneB
27、 1 62.0A Supporting data have been filed atASTM International Headquarters and may beobtained by requesting Research Report RR:E37-1041. Contact ASTM CustomerService at serviceastm.org.B SRM 8456 available from the National Institute for Standards and Technology(NIST), Gaithersburg, MD, USA.E2425 16
28、210.5 Record the loss modulus of the reference material from its certificate or from Table 1 as Es.10.6 Calculate and report the value of the slope (S) and conformity (C) of the measurement using Eq 2 and Eq 3.11. Calculation11.1 For the purpose of this test method, it is assumed that the relationsh
29、ip between the observed loss modulus (Eo) and thereference loss modulus (Es) is linear and governed by the slope (S) of Eq 1.Es 5Eo 3S (1)11.2 By using the loss modulus values taken from 10.4 and 10.5, calculate and report S using Eq 2 to four decimal places.S 5Es/Eo (2)11.3 The conformity (C) (that
30、 is, the percent difference between the experimental slope and unity) of the instrument lossmodulus scale is calculated using the value of S from 11.2 and Eq 3.C 5S 21.0000!3100% (3)11.3.1 Conformity may be estimated to one significant figure using the following criteria:11.3.1.1 If the value of S i
31、s between 0.990 and 0.9999 or between 1.0001 and 1.0010, then the conformity is better than 0.1 %.11.3.1.2 If the value of S is between 0.9000 and 0.9990 or between 1.0010 and 1.0100, then conformity is better than 1 %.11.3.1.3 If the value of S is between 0.9000 and 0.9900 or between 1.0100 and 1.1
32、000, then the conformity is better than 10 %.11.4 Report the value of slope (S) and the conformity (C).12. Report12.1 The report shall include the following information:12.1.1 Details and description of the dynamic mechanical analyzer, including the manufacturer and instrument model number,where app
33、licable. Also report the test mode, strain amplitude, frequency and applied static load.12.1.1.1 Whether or not the instrument calibration included compliance corrections.12.1.2 The value of slope (S) determined in 11.2, reported to at least four decimal places.12.1.3 The conformity (C), as determin
34、ed in 11.3.12.1.4 The specific dated version of this test method used.13. Precision and Bias13.1 An interlaboratory study was conducted in 2010 that included participation by 15 laboratories using 7 instrument modelsfrom 4 = manufacturers. manufacturers.3 A single sample of ultra-high molecular weig
35、ht polyethylene4 was characterized inquintuplicate.13.2 Precision:13.2.1 Within laboratory variability may be described using the repeatability value (r) obtained by multiplying the repeatabilitystandard deviation by 2.8.The repeatability value estimates the 95 % confidence limit.That is, two result
36、s from the same laboratoryshould be considered suspect (at the 95 % confidence level) if they differ by more than the repeatability value.13.2.2 The within laboratory repeatability standard deviation was 2.3 MPa resulting in a repeatability relative standard deviationof 3.8 % with 48 degrees of expe
37、rimental freedom The repeatability value r is 6.7 MPa.13.2.3 The between laboratory variability may be described using the reproducibility value (R) obtained by multiplying thereproducibility standard deviation by 2.8. The reproducibility value estimates the 95 % confidence level. That is, results o
38、btainedby two different laboratories, operators or apparatus should be considered suspect (at the 95 % confidence level) if they differ bymore than the reproducibility value.13.2.4 The between laboratory reproducibility standard deviation 8.6 MPa resulting in a reproducibility relative standarddevia
39、tion of 14 %. The reproducibility value R is 24 MPa.13.3 Bias:13.3.1 Bias is the difference between the mean value obtained and an acceptable reference value for the same material. To theknowledge of the committee, no acceptable loss modulus reference material is available.Therefore, bias is unable
40、to be determined.13.3.2 The mean loss modulus value for the ultra-high molecular weight polyethylene was 62.0 MPa.14. Keywords14.1 calibration; conformity; dynamic mechanical analysis; loss modulus3 Supporting data have been filed at ASTM International Headquarters and may be obtained by requesting
41、Research Report RR:E37-1041. Contact ASTM CustomerService at serviceastm.org.4 SRM 8456 available from the National Institute for Standards and Technology (NIST), Gaithersburg, MD, USA.E2425 163SUMMARY OF CHANGESCommittee E37 has identified the location of selected changes to this standard since the
42、 last issue (E2425 11)that may impact the use of this standard. (Approved June 1, 2016.)(1) Technical change to 10.3.(2) Editorial changes to 3.1, Table 1, and 13.1.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this
43、 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 at any time by the responsible technical committee and must be
44、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 comments will receive careful consideration at a meeting of therespon
45、sible 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 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West
46、 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 164
