1、Designation: D2084 17Standard Test Method forRubber PropertyVulcanization Using Oscillating Disk CureMeter1This standard is issued under the fixed designation D2084; 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope1.1 This test method covers the use of th
3、e oscillating diskcure meter for determining selected vulcanization characteris-tics of vulcanizable rubber compounds.1.2 ISO 3417 is very similar to this test method. It has minortechnical differences that are not considered to be significant.1.3 The values stated in SI units are to be regarded as
4、thestandard. The values given in parentheses are for informationonly.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 standard to establish appro-priate safety, health, and environmental practices an
5、d deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recom-
6、mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Conditions for Test-ingD3185 Test Methods for RubberEvaluation of SBR(Styrene-Butadiene Rubber) Including Mixtures With OilD3186 T
7、est Methods for RubberEvaluation of SBR(Styrene-Butadiene Rubber) Mixed With Carbon Black orCarbon Black and OilD3187 Test Methods for RubberEvaluation of NBR(Acrylonitrile-Butadiene Rubber)D3190 Test Method for RubberEvaluation of ChloropreneRubber (CR)D4483 Practice for Evaluating Precision for Te
8、st MethodStandards in the Rubber and Carbon Black ManufacturingIndustries2.2 ISO Standard:ISO 3417 RubberMeasurement of Vulcanization Charac-teristics With the Oscillating Disk Rheometer33. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 The following measurements may be taken fr
9、om thetorque versus time curve (see Fig. 1).3.1.2 cure rate indexmeasure of rate of vulcanizationbased on the difference between optimum vulcanization andincipient scorch time.3.1.3 peak cure ratemeasure of rate of vulcanizationexpressed as the maximum slope of the torque versus timecurve.3.1.4 maxi
10、mum, plateau, or highest torquemeasure ofstiffness or shear modulus of the fully vulcanized test specimenat the vulcanization temperature.3.1.5 minimum torquemeasure of the stiffness of theunvulcanized test specimen taken at the lowest point of thecurve.3.1.6 time to incipient cure (scorch time)meas
11、ure of thetime at which vulcanization begins.3.1.7 time to a percentage of full curemeasure of curebased on the time to develop some percentage of the highesttorque or difference in torque from the minimum.3.1.8 torquefor an oscillating shear cure meter, the valuemeasured by a torque transducer at t
12、he peak strain amplitude ofthe oscillating cycle.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.12on Processability Tests.Current edition approved Oct. 1, 2017. Published November 2017. Origina
13、llyapproved in 1971. Last previous edition approved in 2011 as D2084 11 (2016).DOI: 10.1520/D2084-17.2For referenced 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 D
14、ocument Summary page onthe ASTM website.3Available from American National Standards Institute, 25 W. 43rd St., 4thFloor, New York, NY 10036.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard was developed in ac
15、cordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.13.1.9 optimum cure timemeasur
16、e of the time required toreach a percentage of full cure that corresponds to a desiredlevel of a property of the cured compound.3.1.9.1 DiscussionThe time to reach 90 % cure corre-sponds to a maximum in tensile strength for some rubbercompounds. This does not apply in all cases.4. Summary of Test Me
17、thod4.1 A test specimen of vulcanizable rubber compound isinserted into the cure meter test cavity and after a closureaction is contained in a sealed cavity under positive pressure.The cavity is maintained at some elevated vulcanizationtemperature. The rubber totally surrounds a biconical disk after
18、the dies are closed (see Fig. 2). The disk is oscillated througha small rotational amplitude (1 or 3) and this action exerts ashear strain on the test specimen.The force required to oscillateor rotate the disk to maximum amplitude is continuouslyrecorded as a function of time, with the force being p
19、ropor-tional to the shear modulus (stiffness) of the test specimen atthe test temperature. This stiffness initially decreases as itwarms up; then it increases due to vulcanization. The test iscompleted when the recorded torque either rises to an equilib-rium or maximum value, or when a predetermined
20、 time haselapsed. The time required to obtain a cure curve is a functionof the characteristics of the rubber compound and of the testtemperature (see Fig. 1 for typical cure curves).4.2 Several configurations of the oscillating disk cure meterare currently in use. Fig. 3 illustrates example shifts o
21、f the curecurves associated with the configuration differences included inthis standard. Results between tests using rapid and slowtemperature recovery, or between heated and unheated diskscannot be compared without taking the heating differences intoaccount. The differences between test curves will
22、 vary with thecompound being tested. Configurations included in this testmethod are listed in this section.Left Curve: Cure to Equilibrium Torque.Middle Curve: Cure to a Maximum Torque with Reversion.Right Curve: Cure to No Equilibrium in Maximum Torque.FIG. 1 Types of Cure CurveFIG. 2 Cure Meter As
23、semblyD2084 1724.2.1 Diaphragm dies, unheated rotor, temperature recoverywithin 4.5 min.4.2.2 Solid dies, unheated rotor, temperature recoverywithin 4.5 min.4.2.3 Solid dies, unheated rotor, temperature recovery inless than 2 min.4.2.4 Solid dies, heated rotor, temperature recovery in lessthan 2 min
24、.NOTE 1Diaphragm dies are unique to cure meters developed beforerapid temperature recovery and heated rotors were introduced. Diaphragmdies in combination with rapid temperature recovery or heated rotors arenot a normal configuration for Oscillating Disk Cure Meters.5. Significance and Use5.1 This t
25、est method is used to determine the vulcanizationcharacteristics of (vulcanizable) rubber compounds.5.2 This test method may be used for quality control inrubber manufacturing processes, for research and developmenttesting of raw-rubber compounded in an evaluationformulation, and for evaluating vari
26、ous raw materials used inpreparing (vulcanizable) rubber compounds.6. Apparatus6.1 Cure meter, consists of the following major components:specimen chamber and closure mechanism, temperature con-trol system, rotor drive and torque measuring system (see Fig.2 for a detailed drawing of cure meter assem
27、bly).6.2 Specimen ChamberConsists of platens, dies, and abiconical disk.6.2.1 PlatensTwo platens made of aluminum alloy, eachcontaining an electric heater, and each having in the center, acavity to accommodate a die and from the side, a well forinserting a temperature sensor.6.2.2 DiesTwo which form
28、 a cavity when closed andwhich shall be fabricated from tool steel having a minimumRockwell Hardness HRC 50. The geometry of the standarddies is shown in Figs. 4-6 with dimensions and tolerances (seeTable 1). The top and bottom surfaces of the die cavity shallcontain rectangular-shaped grooves arran
29、ged radially about thecenter and spaced at 20 intervals. Each die shall have a wellor hole drilled from the side to accommodate a temperaturesensor inserted through the platen. The upper die may be eithersolid or diaphragm type. The lower dies shall have a hole in thecenter to allow for the insertio
30、n of the disk shaft. A suitablelow-friction seal shall be provided in this hole to preventmaterial leaking from the cavity.6.2.2.1 Diaphragm Upper DieUpper die manufactured sothat the grooved die face is allowed to flex when closed on aspecimen and then to maintain essentially constant pressure onth
31、e specimen as it shrinks slightly in volume during vulcani-zation. To provide thermal conduction to the metal body of thediaphragm die, an aluminum or stainless steel insert is placedin the diaphragm space with a hole designed to accommodatethe temperature sensor. Fig. 5 describes the diaphragm type
32、upper die.6.2.2.2 Solid Upper DieUpper die formed from one pieceof steel, as described in Fig. 6.6.2.3 DiskThe biconical disk shall be fabricated from toolsteel having a minimum Rockwell Hardness of HRC 50. Thedisk shall be fitted with a stem that fits into the torque shaft.The disk is shown in Fig.
33、 7 (see Table 2).6.2.3.1 Heated DiskSome manufacturers of oscillatingdisk cure meters offer a heated rotor as an option. If the disk isheated, both torque values and cure times may be significantlyaltered. The heated disk is a modification of the biconical diskshown in Fig. 7. This modification has
34、provisions for directlycontrolling the disk temperature, as shown in Fig. 8. In thisexample, an electrical heater and temperature sensor arelocated in a metal tube, which is inserted in the disk through avertical well in the disk shaft. The well is typically 0.325 cm(0.128 in.) in diameter and exten
35、ds to within approximatelyFIG. 3 Example Cure Curves from ODR ConfigurationsFIG. 4 Lower DieD2084 1730.25 cm (0.100 in.) of the disk apex. The insertion tube istypically 0.0125 cm (0.005 in.) less than the well diameter toallow for easy tube removal for cleaning.6.2.3.2 Disk wear will affect test re
36、sults.Adisk worn to suchan extent that the disk diameter is less than the minimumdiameter shown in this procedure shall not be used.6.2.3.3 The standard frequency of the rotary oscillation ofthe disk shall be constant at 1.67 Hz (100 cpm) 61 %. Otherfrequencies may be used, if required.6.2.3.4 A rot
37、ary drive system shall be provided for oscilla-tory rotation of the disk. The amplitude of oscillation of theunloaded disk shall be constant at 61.00 with a tolerance of60.03 about the center position, that is, a total amplitude of2. Other amplitudes may be used, if specified.NOTE 2Disk and die surf
38、ace contamination may contribute toslippage. Typically, torque values over 40 dNm may be subject to slipping,thus reducing torque values. Torque values approaching 100 dNm are alsotypically compromised by a significant torsion deformation of the diskshaft. Where slipping or torsion deformation is no
39、t a concern, greatersensitivity may be possible using 63 arc of oscillation.6.2.4 Die Closing MechanismA pneumatic cylinder orother device shall close the dies and hold them closed duringthe test with a force of 11.0 6 0.5 kN (2500 6 100 lbf).NOTE 3One manufacturer recommends the source air pressure
40、 beadjusted to 345 kPa (50 psi) for a 203-mm (8-in.) diameter air cylinder.Provisions are made for this adjustment to the instrument. This pressureacting on a 203-mm (8-in.) diameter air cylinder will produce a force of11 kN (2500 lbf) on the die per the following equation:F 5 PSD24D(1)where:F = clo
41、sure force on die,P = source air pressure, andD = diameter of piston in pneumatic cylinder.To calculate maximum cavity pressure, the effect of this force acting onthe surface area of the upper die may be calculated per the followingequation:Pc54Fd2(2)where:Pc= pressure on sample in upper die cavity,
42、 andd = diameter of upper die cavity (55.9 mm (2.2 in.).SFor example , Pc5S4!11! 55.9!2D5 4485 kPa 5 650 psiD(3)6.3 Temperature Controlling SystemA temperature con-troller shall be provided for maintaining the dies within60.5C (61F) of the specified test temperature.6.3.1 Heated Disk Temperature Con
43、trolWhen the disk isheated, a temperature controller shall be provided for main-taining the disk temperature within 60.5C (61F) of thespecified test temperature.6.4 Torque Measuring SystemThe torque measuring sys-tem shall consist of a device, such as a torque transducer,producing a signal that is d
44、irectly proportional to the torquerequired to oscillate the disk. A recording system, as used inthis test method, may consist of any suitable data collectiondevice, including computers, printers, plotters, and chart re-corders. The recording system shall have a full-scale deflectionresponse on the t
45、orque scale of1sorless and be capable ofrecording the torque with accuracy of 60.5 % of the torquerange.Aminimum of four torque ranges shall be provided; 0 to25, 0 to 50, 0 to 100, and 0 to 200 dNm (or 0 to 25, 0 to 50,0 to 100, and 0 to 200 lbf in.)NOTE 4Direct proportionality between torque and st
46、iffness cannot beexpected under all test conditions, particularly in higher torque ranges,because elastic deformation of the disk shaft and driving device must betaken into account. However, for routine quality control test purposescorrections are not necessary.7. Sampling7.1 The sample shall be tak
47、en from a vulcanizable rubbercompound as required by the mixing method or other samplinginstructions.7.2 The sample shall be in sheeted form, at roomtemperature, and as free of air as possible.7.3 The temperature of the sample and its heat history cansignificantly affect test results. For referee te
48、sting and fortesting under controlled circumstances, the sample shall beconditioned at 23 6 1C (73 6 2F) for at least 1 h beforetesting.FIG. 5 Diaphragm Type Upper DieD2084 1747.4 In production control testing, samples may be testedwithout the conditioning period, but care should be taken tominimize
49、 temperature and heat history variations prior totesting.8. Test Specimen8.1 A nearly circular test specimen taken from a sampleshall have a volume of 9.5 6 1.5 cm3(0.58 6 0.09 in.3) (forexample, approximately 30 mm (1.2 in.) in diameter and 13.5mm (0.53 in.) in thickness).8.2 The test specimen is considered to be of proper sizewhen a small bead of compound is extruded uniformly aroundthe periphery of the die as it is closed (116 to 160 % of the testcavity volume). This is achieved when the test specimenvolume is between 8 and
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