ASTM D6049-2003(2008) 488 Standard Test Method for Rubber Property-Measurement of the Viscous and Elastic Behavior of Unvulcanized Raw Rubbers and Rubber Compounds by Compression B.pdf

1、Designation: D 6049 03 (Reapproved 2008)Standard Test Method forRubber PropertyMeasurement of the Viscous and ElasticBehavior of Unvulcanized Raw Rubbers and RubberCompounds by Compression Between Parallel Plates1This standard is issued under the fixed designation D 6049; the number immediately foll

2、owing the designation indicates the year oforiginal adoption or, in the case of revision, the year of last 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

3、 is an adaptation of the GermanStandard DIN 53514, a further development of the former“Defo Test” (see Appendix X1).1.2 This test method is capable of measuring and character-izing the rheological behavior (viscosity and elasticity) ofunvulcanized raw rubbers and rubber compounds, relating tothe mac

4、ro structure of rubber polymers (average molecularweight, molecular weight distribution, long chain branching,and micro- and macro-gel).1.3 The viscosity and elasticity of unvulcanized rubbers andrubber compounds are determined by subjecting cylindricaltest pieces to a compression/recovery cycle. Th

5、e dependencyon shear rate at constant shear stress is evaluated and thematerial fatigue behavior is determined in repeat cycle testing.1.4 The non-Newtonian viscous and elastic behavior ofrubbers and rubber compounds can also be evaluated.1.5 Statistical evaluation of the test data provides an indi-

6、cation of data variation, which may be employed as an estimateof the homogeneity of the material tested.1.6 The values stated in SI units are to be regarded as thestandard. The values in parentheses are for information only.1.7 This standard does not purport to address all of thesafety concerns, if

7、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 ASTM Standards:2D 297 Test Methods for Rubber ProductsChemicalAn

8、alysisD 926 Test Method for Rubber PropertyPlasticity andRecovery (Parallel Plate Method)D 4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD 6048 Practice for Stress Relaxation Testing of Raw Rub-ber, Unvulcanized Rubber Compounds

9、, and ThermoplasticElastomers2.2 DIN Standards:3DIN 53514 Testing of RubberDetermination of Viscosityand Elasticity Related Numbers of Raw Rubber andRubber Mixes in a Compression Test between ParallelPlatesDIN 53523, Part 1 Testing of Rubber and ElastomersTesting with the Mooney Shearing Disk Viscom

10、eter;Preparation of Test Pieces2.3 ISO Standards:4ISO 5725 Precision of Test MethodsDetermination ofRepeatability and Reproducibility for a Standard TestMethod by Interlaboratory TestsISO 7323 RubberRaw and Unvulcanized CompoundedDetermination of Plasticity Number and Recovery Num-ber; Parallel Plat

11、e Method3. Terminology3.1 DefinitionsThe following terms appear in logicalorder for the sake of clarity.3.1.1 Multiple Compression Force Testrefer to Section 10for more details.3.1.1.1 viscosity number, V10(Ns)the product of the forceF in N required to compress a test piece the final 0.5 mm (0.021Th

12、is test method is under the jurisdiction of Committee D11 on Rubber and isthe direct responsibility of Subcommittee D11.12 on Processability Tests.Current edition approved May 1, 2008. Published June 2008. Originallyapproved in 1996. Last previous edition approved in 2003 as D 6049 03.2For reference

13、d 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 onthe ASTM website.3Available from Deutsches Institut fr Normung, Burggrafenstr 6, D 10787Berl

14、in 30, Germany.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.in.) in a 6.0 mm (0.24 in.) total compression cycle (from 13.0t

15、o 7.0 mm (0.51 to 0.28 in.) and the compression time dt1equaling 10 s.3.1.1.2 total compression time, tTthe time in s required tocompress a test piece the full 6.0 mm (0.24 in.), that is, from13.0 to 7.0 mm (0.51 to 0.28 in.).3.1.1.3 elasticity number, DE30the elastic recovery ex-pressed in units of

16、 0.1 mm (0.004 in.) calculated from theheight h2of the test piece after compression from 13.0 to 7.0mm (0.51 in. to 0.28 in.) within 30 s followed by a recoveryperiod of 30 s.3.1.1.4 non-Newtonian viscosity exponent, n1the slope ofthe line in a double log plot of the viscosity versus the shearrate;

17、n1is dimensionless and always negative.3.1.1.5 elasticity coeffcient, mthe slope of the line in aplot of the elasticity number DE (see 3.1.2.3) versus the log ofthe shear rate; the dimension of m is mm (in units of 0.1 mmper decade).3.1.1.6 test data variation number, svthe average standarddeviation

18、 of the data points of the individual test pieces, fromthe regression line of the viscosity number in accordance with3.1.1.4.3.1.1.7 test data variation number, sethe average standarddeviation of the data points of the individual test pieces fromthe regression line of the elasticity number in accord

19、ance with3.1.1.5.(a) DiscussionBoth numbers, svand se, can be used to(1) characterize the homogeneity of the test pieces or (2)provide an estimate of the test precision where test pieces areknown to be homogeneous. In addition, secan indicate rarecases of nonlinearity.3.1.1.8 viscous material fatigu

20、e, DV21the decrease inpercent of V10for the first compression compared to V10for thesecond compression.(a) DiscussionWhen the first compression/recoverycycle (compression time = recovery time) is repeated, theviscosity number of the second cycle will be lower than that ofthe first cycle.3.1.1.9 elas

21、tic material fatigue, Q21the quotient of therecovery times, (tRV)2and (tRV)1, after the second and firstcompression/recovery cycle, allowing the test piece to reachequivalent recovery heights in both cycles; Q21is dimension-less.(a) DiscussionIn the second compression/recoverycycle the test piece re

22、quires a longer recovery time to reach thesame height as in the first cycle.3.1.2 Single Compression Force Testrefer to Section 10for more details.3.1.2.1 viscosityspecific to this test method, the ratio ofcompression force to compression time, where compressionforce and compression time are proport

23、ional to shear stress andshear rate, respectively.(a) DiscussionThe compression force F specified for aparticular material determines the deformation stress, and thecompression time dt1required to compress a test piece the final0.5 mm (0.02 in.) in a 6.0 mm (0.24 in.) total compressioncycle (from 13

24、.0 to 7.0 mm (0.51 to 0.28 in.) determines thedeformation rate.3.1.2.2 total compression time, tTrefer to 3.1.1.2.3.1.2.3 elastic recovery, DEcalculated from the height h2of the test piece after compression from 13.0 to 7.0 mm (0.51in. to 0.28 in.) followed by a recovery period, equal in lengthto th

25、e compression time, expressed in units of 0.1 mm (0.004in.).3.1.2.4 non-Newtonian viscosity number, qthe quotient ofthe two compression time values dt1and tT(see 3.1.2.1 and3.1.1.2); q is dimensionless.3.1.2.5 test data variationthe standard deviations srforthe compression time dt1(3.1.2.1) and srfo

26、r the elasticrecovery DE (3.1.2.3).(a) Discussionsee 3.1.1.7.3.1.2.6 viscous material fatigue, D dt21the decrease inpercent of the compression time dt2versus the compressiontime dt1.(a) DiscussionWhen the first compression/recoverycycle (compression time = recovery time) is repeated with thesame for

27、ce, the compression time dt2of the second cycle willbe lower than the compression time dt1of the first cycle.4. Summary of Test Method4.1 This test method provides procedures for preparingcylindrical test pieces of specified diameter and height fromunvulcanized raw rubbers and rubber compounds and f

28、ortesting their viscous and elastic behavior at a specified tem-perature in a compression/recovery operation between parallelplates.4.2 The compression device is mounted in an environmentalchamber. The preferred test temperature is 105C (221F).4.3 The change in test piece height is measured under ac

29、onstant compression force and in the recovery phase afterreleasing the force.4.4 Viscosity is characterized by compression force andcompression time, elasticity by the recovery height of the testpiece after release of the compression force (recovery phase).Material fatigue is measured through repeat

30、 compression/recovery cycles.4.5 The test can be performed with multiple compressionforces for a more comprehensive evaluation of the viscous andelastic properties, including non-Newtonian behavior, or with atime saving single compression force, preferred in qualitycontrol to test primarily uniformi

31、ty of viscosity and elasticity.4.6 Statistical evaluation of the test results gives an indica-tion of data scatter, and permits also an assessment of thehomogeneity of the material under test.5. Significance and Use5.1 The viscous and elastic behavior of unvulcanized rub-bers and rubber compounds is

32、 of paramount importance inrubber manufacturing, since it affects processing, such asmixing, calendering, extrusion, and molding.The uniformity ofthese properties is equally important, as fluctuations will causeupsets in manufacturing processes.5.2 A test capable of measuring viscosity and elasticit

33、y ofunvulcanized rubbers and rubber compounds, including theiruniformity and prediction of processing behavior, is thereforehighly desirable (see Practice D 6048 for further information).D 6049 03 (2008)25.3 Compared to many other rheological tests, this testmethod measures viscosity and elasticity

34、related parametersunder conditions of low shear and has a high discriminatingpower. It can detect small rheological differences. A fulldiscussion of the principles behind stress relaxation testing isgiven in Practice D 6048.5.4 Test results of this test method may be useful inpredicting processabili

35、ty, but correlation with actual manufac-turing processes must be established in each individual case,since conditions vary too widely.5.5 This test method is suitable for specification compliancetesting, quality control, referee purposes, and research anddevelopment work.6. Interferences6.1 For reli

36、able test results it is important that test pieces areof accurate dimensions, are free of air inclusions and blisters,and contain negligible residual stresses.6.2 Although this test method is practically unlimited intesting unvulcanized rubbers, it may be necessary to considersmaller test pieces in

37、the case of very hard and rigid sub-stances.7. Apparatus57.1 Compression Device:7.1.1 Two circular platens with a diameter of 30.0 6 0.1mm (1.181 6 0.004 in.) and a thickness of at least 2 mm (0.08in.) mounted in an angle iron frame, are facing each otherhorizontally. The upper platen can be vertica

38、lly moved andraised at least 14 mm (0.55 in.) above the lower platen topermit insertion of the 13-mm (0.51-in.) high test piece.7.1.2 The upper platen shall be able to move nearly withoutfriction, that is, it must smoothly descend under the contactforce specified in 7.1.5.7.1.3 The upper platen shal

39、l be capable of applying acompressive force between 1 and 800 N (0.22 and 180 lbf) 60.5 % to the test piece within 1 s. The force should be appliedrapidly but not abruptly.7.1.4 After the height of the test piece has been reducedfrom 13.0 to 7.0 mm (0.51 to 0.28 in.) the compression forceshall be re

40、leased in less than 0.5 s.7.1.5 A residual compression force of 0.040 6 0.005 N(0.009 6 0.001 lbf) shall always be maintained by the upperplaten to warrant an intimate contact with the test piece prior tocompression and during the recovery cycle. The mass of theupper platen must be taken into accoun

41、t and compensated for.7.1.6 The position of the upper platen shall be continuouslyrecorded during the test to the nearest 0.01 mm (0.0004 in.) inat least 0.05 s intervals. The starting time of the compressioncycle, the time of reaching compression heights of 7.5 and 7.0mm (0.30 and 0.28 in.), and th

42、e recovery times shall berecorded to the nearest 0.05 s.7.1.7 The compressed test pieces shall only be in contactwith the two platens and the platens shall be kept free ofcontamination. The test piece arrangement is illustrated in Fig.1.7.2 Test Chamber:7.2.1 The compression device shall be containe

43、d in a testchamber that can be temperature controlled between 20 and170 6 1C (68 and 338 6 2F).7.2.2 The test chamber shall have holding devices to ac-commodate test pieces of 13.0 6 0.1 mm (0.51 6 0.004 in.)plus twice the thickness of the sandpaper in height forconditioning.7.3 Recording and Evalua

44、tion of Test Results:7.3.1 The test shall be run and controlled automatically,including recording of the compression heights and times.7.3.2 Evaluation of test results is best carried out immedi-ately after the test. The use of a computer to control the testsequence and record data is recommended.8.

45、 Preparation of Test Pieces8.1 The cylindrical test piece shall have a height of 13.0 60.1 mm (0.51 6 0.004 in.) and a diameter of 30.0 6 0.1 mm(1.18 6 0.004 in.). It is typically produced by molding andshould be free of blisters and internal residual stresses. Sand-paper disks6shall be molded to th

46、e top and bottom of thecylindrical test piece to stabilize the surfaces and ensure aneven transmission of the compression forces without slippage.The sandpaper facing also prevents fouling of the platens of thecompression device and can be used for identification pur-poses.8.2 Test Pieces from Rubbe

47、r in Bale Form:8.2.1 Sheets of approximately 2 mm (0.08 in.) in thicknessare sliced from the bale, and disks of approximately 30 mm(1.18 in.) in diameter are die cut from these sheets. The disksare loosely plied up to produce a specimen sufficiently large involume for a test piece, including a mold

48、flash of 0.05 to 0.35g.5A suitable instrument can be obtained under the name Defo-Elastometer(System Bayer) from Haake, Inc., West Century Road, Paramus, NJ 07652, orHaake G.m.b.H., Dieselstr., D76227 Karlsruhe, Germany.6A suitable sandpaper is 3M 230N (120 grit, aluminum oxide) available from3M Abr

49、asive Systems Div., 3M Center, St. Paul, MN 55144, or 3M 204 (120 grit,aluminum oxide) available from Fa. Krueckemeyer, D57225 Wilmsdorf, Germany.FIG. 1 Test Piece ArrangementD 6049 03 (2008)38.2.2 The mass of material required for a test piece can bederived from the density of the material and the test piecevolume of approximately 9.2 cm3(0.56 in.3)(mass = volume 3 density). It is also necessary to consider thesandpaper with a density of approximately 1.28 g/cm3(for twodisks per test piece a mass of 0.34 g and a thickness of 0.38 mmis typic