1、Designation: E 2347 05Standard Test Method forIndentation Softening Temperature by ThermomechanicalAnalysis1This standard is issued under the fixed designation E 2347; 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 (e) 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 methoddesc
3、ribes 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 D 1525) of a testspecimen is realized by indentation measurement using athermomechanical analyzer as the test specimen is heated. Thistemperature is iden
4、tified 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 D 1525 but is performed on a thermomechanical analyzerusing a smaller diameter indenting prob
5、e. Equivalence of results to thoseobtained by Test Method D 1525 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 D 1525.1.2 This test method is no
6、t recommended for ethyl cellu-lose, poly (vinyl chloride), poly (vinylidene chloride) and othermaterials having a large measurement imprecision (see TestMethod D 1525 and sections 5.3 and 14.1.2).1.3 SI values are the standard.1.4 There is no ISO standard equivalent to this test method.1.5 This stan
7、dard 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 applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 A
8、STM Standards:2D 1525 Test Method for Vicat Softening Temperature ofPlasticsE 473 Terminology Relating to Thermal AnalysisE 1142 Terminology Relating to Thermophysical PropertiesE 1363 Test Method for Temperature Calibration of Ther-momechanical AnalyzersE2113 Test Method for Length Change Calibrati
9、on ofThermomechanical AnalyzersE 2206 Test Method for Force Calibration of Thermome-chanical Analyzers3. Terminology3.1 DefinitionsSpecific technical terms used in this stan-dard are defined in Terminologies E 473 and E 1142.3.1.1 penetration softening temperature, C , nthe tem-perature at which a t
10、est specimen has a modulus of either 6.65or 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 probe. Therelationship between modulus of a material (stress divided bystrain) and penet
11、ration 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 upon heating. For such materials,the modulus may be determined by penetration as th
12、e sampleis heated. This test method identifies the temperature at whichthe modulus of the specimen is 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
13、test specimen as it is heated at a constant ratefrom ambient temperature to the upper temperature limit forthe material. The penetration (that is, deflection) of the test1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcom
14、mittee E37.01 on ThermalAnalysis and Rheology Methods.Current edition approved Sept. 1, 2005. Published October 2005. Originallyapproved in 2004. Last previous edition approved in 2004 as E 234704.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service a
15、t 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.specimen is recorded as a function of temperature
16、. 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. Significance and Use5.1 Data obtained by this test method shall not be used topredict the behavior of materials at elevate
17、d 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 particularly suited for quality controland development work. The data are not intended for use indesign or predicting endur
18、ance at elevated temperatures.5.3 Ruggedness testing indicates that some materials, suchas poly (vinyl chloride) exhibit substantially greater impreci-sion than that described in Section 14 for “well behaved”materials.6. Apparatus6.1 A thermomechanical analyzer consisting of:6.1.1 Rigid Specimen Hol
19、der, 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 expansivitymaterial ( 1 m m-1C-1) that contacts the specimen with anapplied compression force (see Fig. 1). The tip shal
20、l 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 Element, having a linear outputover a minimum range of 5 mm to measure the displacement ofthe rigid penetration probe (s
21、ee 6.1.2) to within 6 0.1 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 penetration probe (see 6.1.2).NOTE 3Other forces may be used but shall be reported.6.1.5 Temperature Sensor, that can be po
22、sitioned 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 oftemperature 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 o
23、f 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 argon. Dry gases are recommended forall experiments unless the effect of moisture is part of the study.6.1.8 Recordi
24、ng Device, to record and display the experi-mental parameters of penetration on the Y-axis (ordinate) to asensitivity of 6 0.1 mm and of temperature on the X-axis(abscissa) to a sensitivity of 6 0.1 C.6.1.9 Calipers, Micrometer, or other length measuring de-vice capable of a length measurement of up
25、 to 2 mm with aprecision of 6 1 m.7. Hazards7.1 Toxic or corrosive effluents, or both, may be releasedwhen heating some materials and could be harmful to person-nel and to apparatus.8. Sampling, Test Specimens, and Test Units8.1 Because the specimen size is small, care shall be takento ensure that e
26、ach specimen is homogeneous and representa-tive of the sample as a whole.8.2 The specimen may be cut 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
27、mm.FIG. 1 Penetration ProbeE23470528.4 This standard assumes that the material is isotropic.Should specimens be anisotropic, such as in reinforced com-posites, the direction of the reinforcing agent shall be reportedrelative to the compression (specimen) dimensions.9. Preparation of Apparatus9.1 Per
28、form any setup or calibration procedures recom-mended by the apparatus manufacturer in the operationsmanual.10. Calibration and Standardization10.1 Calibrate the temperature display of the apparatusaccording to Test Method E 1363 using a heating rate of 2.0 60.2 C/min.10.2 Calibrate the deflection d
29、isplay of the apparatus ac-cording to Test Method E2113.10.3 Calibrate the mechanism for applying force to the testspecimen according to Test Method E 2206.11. Procedure11.1 Measure the diameter of the circular penetration tip ofthe penetration probe to 6 1 m and record this value as D.11.2 Method A
30、: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 Force (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 experime
31、ntalendpoint to three significant figures.11.3.2.2 Center the test specimen on the stage with a surfaceperpendicular to the loading nose 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)
32、. 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 until the deflection d (determined in11.3.2.1) is obtained while recording specimen deflection andtemperature. Once the deflection value is achieved, terminatethe tem
33、perature program and remove the load from the testspecimen. Cool the apparatus to ambient temperature.11.3.2.5 Record the temperature at the deflection value dasthe estimated indentation softening temperature (T).11.3.2.6 For ease of interpretation, record the thermal curvewith penetration displayed
34、 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, place 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 t
35、o 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 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 t
36、he deflection of the baseline at tempera-ture T and record it as do.NOTE 5dois positive for a baseline that expands with temperature andnegative 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)
37、 to be usedas the experimental endpoint.11.3.4.2 Center the test specimen on the stage with a surfaceperpendicular to the loading nose 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).
38、Set the deflection signal to zero atambient temperature.NOTE 6During heating, the test specimen may expand (see Fig. 2).Nonetheless, the deflection value is taken from the original dimension ofthe test specimen measured at ambient conditions. This corresponds withthe conditions of D 1525. Intralabor
39、atory studies show that using theoriginal dimension compared to the maximum dimension produces a0.7 C increase in the value for T. This 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 belowth
40、is 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) is obtained while recording specimendeflection and temperature. Once the deflection value isachieved, terminate the temperature program and remove theload from the t
41、est specimen. Cool the apparatus to ambienttemperature.11.3.4.5 Record the temperature at the deflection value d asthe indentation softening 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 illustra
42、ted 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 = 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/m212.1.1 For examp
43、le, if:E = 6.65 MPa,F = 0.15 N,D = 0.889 mm, anddo= -0.0003 mm13. Report13.1 Report the following information:E234705313.1.1 Complete identification and description of the mate-rial tested including source, manufacturer code and any ther-mal or mechanical pretreatment.13.1.2 Description of the instr
44、ument used, including modelnumber and location of the temperature sensor.13.1.3 Details of the procedure used to calculate the pen-etration softening temperature including strain and resultingforce, stress and resultant strain, as well as specimen dimen-sions.13.1.4 Heating rate, C/min, and temperat
45、ure 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 specific 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
46、 (6.65 MPamodulus) and Method B (33.3 MPa modulus). Twelve labora-tories participated in the test using six instrument models fromthree manufacturers3.14.2 Precision14.2.1 Within laboratory variability may be described usingthe repeatability value (r) obtained by multiplying the repeat-ability stand
47、ard deviation by 2.8. The repeatability valueestimates the 95 % confidence limit, That is, two results fromthe same laboratory should be considered suspect (at the (95 %confidence level) if they differ by more than the repeatabilityvalue.14.2.2 The within laboratory repeatability standard devia-tion
48、 obtained for Method A (6.65 MPa modulus) was 1.1 Cwith 36 degrees of experimental freedom.3A Research Report is available from ASTM Headquarters. RequestRR:E371034.FIG. 2 Penetration Curve of PolystyreneE234705414.2.3 The within laboratory repeatability standard devia-tion obtained for Method B (33
49、.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 from two different laboratories, operators or apparatusshould be considered suspect (at the 95 % confidence level) ifthey differ by more than the repeatability value.14.2.5 The between laboratory reproducibility standard de-vi
