1、Designation: E2347 11Standard Test Method forIndentation Softening Temperature by ThermomechanicalAnalysis1This standard is issued under the fixed designation E2347; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last
2、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 is applicable to materials that softenupon heating to a modulus less than 6.0 MPa. This test methoddescrib
3、es the determination of the temperature at which thespecific modulus of either 6.65 (Method A) or 33.3 MPa(Method B) (equivalent to Test Method D1525) of a testspecimen is realized by indentation measurement using athermomechanical analyzer as the test specimen is heated. Thistemperature is identifi
4、ed as the indentation softening tempera-ture. The test may be performed over the temperature range ofambient to 300 C.NOTE 1This test method is intended to provide results similar to thoseof Test Method D1525 but is performed on a thermomechanical analyzerusing a smaller diameter indenting probe. Eq
5、uivalence of results to thoseobtained by Test Method D1525 has been demonstrated on a limitednumber of materials. Until the user demonstrates equivalence, the resultsof this Test Method shall be considered to be independent and unrelated tothose of Test Method D1525.1.2 This test method is not recom
6、mended for ethyl cellu-lose, poly (vinyl chloride), poly (vinylidene chloride) and othermaterials having a large measurement imprecision (see TestMethod D1525 and 5.3 and Section 14).1.3 The values stated in SI units are to be regarded asstandard. No other units of measurement are included in thisst
7、andard.1.4 There is no ISO standard equivalent to this test method.1.5 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 health practices and determine the ap
8、plica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D1525 Test Method for Vicat Softening Temperature ofPlasticsE473 Terminology Relating to Thermal Analysis and Rhe-ologyE1142 Terminology Relating to Thermophysical PropertiesE1363 Test Method for Temperatu
9、re Calibration of Ther-momechanical AnalyzersE2113 Test Method for Length Change Calibration ofThermomechanical AnalyzersE2206 Test Method for Force Calibration Of Thermomech-nical Analyzers3. Terminology3.1 DefinitionsSpecific technical terms used in this stan-dard are defined in Terminologies E473
10、 and E1142.3.1.1 penetration softening temperature, C , nthetemperature at which a test specimen has a modulus of either6.65 or 33.3 MPa as measured in penetration.4. Summary of Test Method4.1 The modulus of a material may be determined by theindentation (penetration) of a circular, flat tipped prob
11、e. Therelationship between modulus of a material (stress divided bystrain) and penetration depth is given by:E 5 3 F / 4 Dd! (1)where:E = modulus, MPa,F = force, N,D = diameter of a circular, flat tipped probe, mm, andd = penetration depth, mm.NOTE 2Note the identity Pa=N/m24.2 Some materials soften
12、 upon heating. For such materials,the modulus may be determined by penetration as the sample1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.10 on Funda-mental, Statistical and Mechanical Properties.Current e
13、dition approved April 1, 2011. Published May 2011. Originallyapproved in 2004. Last previous edition approved in 2005 as E2347 05. DOI:10.1520/E2347-11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMSta
14、ndards 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.is heated. This test method identifies the temperature at whichthe modulus of the specimen is
15、determined to be 6.65 MPa(Method A) or 33.3 MPa (Method B).4.3 Specifically, a test specimen is tested in penetrationusing a circular, flat tipped probe. A known stress is applied tothe center of a test specimen as it is heated at a constant ratefrom ambient temperature to the upper temperature limi
16、t forthe material. The penetration (that is, deflection) of the testspecimen is recorded as a function of temperature. Thetemperature at which the modulus of the specimen is deter-mined to be 6.65 MPa (Method A) or 33.3 MPa (Method B) isdetermined to be the penetration softening temperature.5. Signi
17、ficance and Use5.1 Data obtained by this test method shall not be used topredict the behavior of materials at elevated temperaturesexcept in applications in which the conditions of time, tem-perature, method of loading, and stress are similar to thosespecified in the test.5.2 This standard is partic
18、ularly suited for quality controland development work. The data are not intended for use indesign or predicting endurance at elevated temperatures.5.3 Ruggedness testing indicates that some materials, suchas poly (vinyl chloride) exhibit substantially greater impreci-sion than that described in Sect
19、ion 14 for “well behaved”materials.6. Apparatus6.1 A thermomechanical analyzer consisting of:6.1.1 Rigid Specimen Holder, of inert, low expansivitymaterial ( 1 m m-1C-1) to center the specimen in the furnaceand to fix the specimen to mechanical ground.6.1.2 Rigid Penetration Probe, of inert, low exp
20、ansivitymaterial ( 1 m m-1C-1) that contacts the specimen with anapplied compression force (see Fig. 1). The tip shall be 0.1 to1.0 mm in diameter, free of burrs and be perpendicular to theaxis of the probe. The tip shall protrude at least 0.1 mm fromthe end of the probe.6.1.3 Deflection Sensing Ele
21、ment, having a linear outputover a minimum range of 5 mm to measure the displacement ofthe rigid penetration probe (see 6.1.2) to within 60.1 m.6.1.4 Programmable Force Transducer, to generate a con-stant force (6 2.5 %) between 0.05 and 1.0 N that is applied tothe specimen through the rigid penetra
22、tion probe (see 6.1.2).NOTE 3Other forces may be used but shall be reported.6.1.5 Temperature Sensor, that can be positioned reproduc-ibly in close proximity to the specimen to measure its tempera-ture over the range of 25 to 300 C to 6 0.1 C.6.1.6 Temperature Programmer and Furnace, capable oftempe
23、rature programming the test specimen from ambient to300 C at a linear rate of at least 2.0 6 0.2 C/min.6.1.7 Means of Providing a Specimen Environment, of inertgas at a purge rate of 50 mL/min 6 5%.NOTE 4Typically, inert purge gas that inhibits specimen oxidation are99.9+ % pure nitrogen, helium or
24、argon. Dry gases are recommended forall experiments unless the effect of moisture is part of the study.6.1.8 Data Collection Device, to provide a means of acquir-ing, storing, and displaying measured or calculated signals, orboth. The minimum output signals required are a change inlinear dimension t
25、o a sensitivity of 60.1 mm, and temperatureto a sensitivity of 61 um.6.1.9 Calipers, Micrometer, or other length measuring de-vice capable of a length measurement of up to 2 mm with aprecision of 61 m.7. Hazards7.1 Toxic or corrosive effluents, or both, may be releasedwhen heating some materials and
26、 could be harmful to person-nel and to apparatus.FIG. 1 Penetration ProbeE2347 1128. Sampling, Test Specimens, and Test Units8.1 Because the specimen size is small, care shall be takento ensure that each specimen is homogeneous and representa-tive of the sample as a whole.8.2 The specimen may be cut
27、 from sheets, plates or moldedshapes, or may be molded to the desired finished dimensions.8.3 A typical test specimen is a rectangle 78 3 78 mm ora circle 78 mm in diameter with a thickness of 1 to 3 mm.8.4 This standard assumes that the material is isotropic.Should specimens be anisotropic, such as
28、 in reinforced com-posites, the direction of the reinforcing agent shall be reportedrelative to the compression (specimen) dimensions.9. Preparation of Apparatus9.1 Perform any setup or calibration procedures recom-mended by the apparatus manufacturer in the operationsmanual.10. Calibration and Stan
29、dardization10.1 Calibrate the temperature display of the apparatusaccording to Test Method E1363 using a heating rate of 2.0 60.2 C/min.10.2 Calibrate the deflection display of the apparatus ac-cording to Test Method E2113.10.3 Calibrate the mechanism for applying force to the testspecimen according
30、 to Test Method E2206.11. Procedure11.1 Measure the diameter of the circular penetration tip ofthe penetration probe to 61 m and record this value as D.11.2 Method A:11.2.1 Set the value of Force (F) at 0.15 6 0.004 N.11.2.2 Proceed with steps 11.3.2-11.3.4.6.11.3 Method B:11.3.1 Set the value of Fo
31、rce (F) to 0.75 6 0.01 N.11.3.2 Perform Scouting Experiment:11.3.2.1 Using Eq 2 and an estimated value of do=0,estimate the deflection (d) to be used as the experimentalendpoint to three significant figures.11.3.2.2 Center the test specimen on the stage with a surfaceperpendicular to the loading nos
32、e of the penetration probe.11.3.2.3 Load the penetration probe onto the center of thetest specimen with the force determined in 11.2.1 (Method A)or 11.3.1 (Method B). Set the deflection signal to zero atambient temperature.11.3.2.4 Heat the test specimen at 2.0 6 0.2 C min-1fromambient temperature u
33、ntil the deflection d (determined in11.3.2.1) is obtained while recording specimen deflection andtemperature. Once the deflection value is achieved, terminatethe temperature program and remove the load from the testspecimen. Cool the apparatus to ambient temperature.11.3.2.5 Record the temperature a
34、t the deflection value dasthe estimated indentation softening temperature (T).11.3.2.6 For ease of interpretation, record the thermal curvewith penetration displayed on the Y-axis and temperature onthe X-axis as illustrated in Fig. 2.11.3.3 Determine the Baseline:11.3.3.1 With no sample present, pla
35、ce the tip of thepenetration probe onto the center of the sample stage. Load theprobe with the force determined in 11.2.1 or 11.3.1. Set thedeflection scale signal to be zero at ambient temperature.11.3.3.2 Heat the sample area at 2.0 6 0.2 C min-1fromambient temperature to a temperature 5 C higher
36、than Tdetermined in 11.3.2.5. Once the temperature program iscomplete, remove the load from the probe and cool theapparatus to ambient temperature.11.3.3.3 Measure the deflection of the baseline at tempera-ture T and record it as do.NOTE 5dois positive for a baseline that expands with temperature an
37、dnegative if the baseline contracts.11.3.4 Test Specimen:11.3.4.1 Using Eq 2 and the value for dofrom 11.3.3.3,determine to three significant figures the deflect (d) to be usedas the experimental endpoint.11.3.4.2 Center the test specimen on the stage with a surfaceperpendicular to the loading nose
38、of the penetration probe.11.3.4.3 Load the penetration probe onto the center of thetest specimen with the force determined in 11.2.1 (Method A)or 11.3.1 (Method B). Set the deflection signal to zero atambient temperature.NOTE 6During heating, the test specimen may expand (see Fig. 2).Nonetheless, th
39、e deflection value is taken from the original dimension ofthe test specimen measured at ambient conditions. This corresponds withthe conditions of D1525. Intralaboratory studies show that using theoriginal dimension compared to the maximum dimension produces a0.7 C increase in the value for T. This
40、is within experimental error (seesection 14).11.3.4.4 Using the appropriate softening temperature deter-mined in 11.3.2.5 start the temperature program 50 C belowthis temperature and heat the test specimen at 2.0 6 0.2 Cmin-1from ambient temperature until the deflection d (deter-mined in 11.3.4.1) i
41、s obtained while recording specimendeflection and temperature. Once the deflection value isachieved, terminate the temperature program and remove theload from the test specimen. Cool the apparatus to ambienttemperature.11.3.4.5 Record the temperature at the deflection value d asthe indentation softe
42、ning temperature ( T).11.3.4.6 For ease of interpretation, record the thermal curvewith penetration displayed on the Y-axis and temperature onthe X-axis as illustrated in Fig. 2.12. Calculation12.1 Calculate the deflection value as follows:d 5 3 F/4 DE! 2 do(2)where:E = modulus, MPa,F = force, N,D =
43、 diameter of a circular, flat tipped probe, mm,d = penetration depth, mm, anddo= baseline depth at temperature T, mm.NOTE 7Note the identity Pa=N/m2E2347 11312.1.1 For example, if:E = 6.65 MPa,F = 0.15 N,D = 0.889 mm, anddo= -0.0003 mm13. Report13.1 Report the following information:13.1.1 Complete i
44、dentification and description of the mate-rial tested including source, manufacturer code and any ther-mal or mechanical pretreatment.13.1.2 Description of the instrument used, including modelnumber and location of the temperature sensor.13.1.3 Details of the procedure used to calculate the pen-etra
45、tion softening temperature including strain and resultingforce, stress and resultant strain, as well as specimen dimen-sions.13.1.4 Heating rate, C/min, and temperature range.13.1.5 A copy of all original records that are presented.13.1.6 The penetration softening temperature ( T),C,and13.1.7 The sp
46、ecific dated version of this test method used.14. Precision and Bias14.1 An interlaboratory study was conducted in 2005 inwhich polystyrene was tested using Method A (6.65 MPamodulus) and Method B (33.3 MPa modulus). Twelve labora-tories participated in the test using six instrument models fromthree
47、 manufacturers.314.2 Precision :14.2.1 Within laboratory variability may be described usingthe repeatability value (r) obtained by multiplying the repeat-ability standard deviation by 2.8. The repeatability valueestimates the 95 % confidence limit, That is, two results from3Supporting data have been
48、 filed at ASTM International Headquarters and maybe obtained by requesting Research Report RR:E37-1034.FIG. 2 Penetration Curve of PolystyreneE2347 114the same laboratory should be considered suspect (at the (95 %confidence level) if they differ by more than the repeatabilityvalue.14.2.2 The within
49、laboratory repeatability standard devia-tion obtained for Method A (6.65 MPa modulus) was 1.1 Cwith 36 degrees of experimental freedom.14.2.3 The within laboratory repeatability standard devia-tion obtained for Method B (33.3 MPa modulus) was 1.1 Cwith 36 degrees of experimental freedom.14.2.4 The between laboratory variability may be describedusing the reproducibility value (R) obtained by multiplying thereproducibility standard deviation by 2.8. The reproducibilityvalue estimates the 95 % confidence limit. That is, resultsobtained