1、Designation: D5289 12Standard Test Method forRubber PropertyVulcanization Using Rotorless CureMeters1This standard is issued under the fixed designation D5289; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisi
2、on. 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 covers a method for the measurementof selected vulcanization characteristics of rubber compoundsusing unsealed a
3、nd sealed torsion shear cure meters. The twotypes of instruments may not give the same results.NOTE 1An alternative method for the measurement of vulcanizationcharacteristics is given in Test Method D2084.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parent
4、heses are for informationonly.1.3 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 applica-bility of regulatory limitation
5、s prior to use.2. Referenced Documents2.1 ASTM Standards:2D1349 Practice for RubberStandard Temperatures forTestingD1566 Terminology Relating to RubberD2084 Test Method for Rubber PropertyVulcanizationUsing Oscillating Disk Cure MeterD4483 Practice for Evaluating Precision for Test MethodStandards i
6、n the Rubber and Carbon Black ManufacturingIndustries3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 rotorless cure meter, na name for a class of curemeters that uses one of the two specimen shaping members ordies to sense the torque or stress during strain application.Rotorle
7、ss cure meters do not have a third member in the formof a rotor (see definitions of cure meter in Terminology D1566and Test Method D2084).3.1.2 S torque, nfor an oscillating shear rotorless curemeter, the value measured by a torque transducer at the peakstrain amplitude of the oscillating cycle; rep
8、resents the elasticresponse of the test material.3.1.3 The following measurements may be taken from therecorded curve of torque as a function of time (see Fig. 1):3.1.3.1 minimum S torquemeasure of the elastic stiffnessof the unvulcanized test specimen at the specified vulcanizingtemperature, taken
9、at the lowest point in the vulcanizationcurve.3.1.3.2 maximum, plateau, or highest S torquemeasureof the elastic stiffness of the vulcanized test specimen at thespecified vulcanizing temperature, measured within a specifiedperiod of time.3.1.3.3 time to a percentage of full curemeasure of curebased
10、on the time to develop some percentage of the differencein S torque from the minimum to the maximum.3.1.3.4 time to incipient cure (scorch time)measure of thetime at which a specified small increase in S torque hasoccurred; it indicates the beginning of vulcanization.3.1.4 S” torque, nfor an oscilla
11、ting shear rotorless curemeter, the value measured by a torque transducer at zero strainamplitude of the oscillating cycle; represents the viscousresponse of the test material (see Fig. 2).3.1.5 S* torque, nfor an oscillating shear rotorless curemeter, the maximum value measured by a torque transduc
12、erduring the oscillating cycle (see Fig. 2).3.1.6 The relationship between S*, S, and S” for anyoscillating cycle is:S* 5 =S !21 S ”!2(1)3.1.7 phase angle d, nfor an oscillating shear cure meter,the angle of shift between the sinusoidal strain and thesinusoidal S* torque during the oscillating cycle
13、 (see Fig. 2).3.1.8 Tan d, nfor an oscillating shear rotorless curemeter, the tangent of the phase angle d.3.1.8.1 DiscussionThe relationship between Tan d, S,and S” is:1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.12
14、on Processability Tests.Current edition approved May 1, 2012. Published June 2012. Originallyapproved in 1992. Last previous edition approved in 2007 as D5289 07a. DOI:10.1520/D5289-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceast
15、m.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.Tan d5S ”S (2)3.1.9 The following measurements may be taken f
16、rom therecorded S” and Tan d curves as a function of time (see Fig. 1):3.1.9.1 S” MLvalue of S” torque when the minimum Storque is taken.3.1.9.2 Tan d MLvalue of Tan d when the minimum Storque is measured.3.1.9.3 S” MHvalue of S” torque when the maximumS torque is taken.3.1.9.4 Tan d MHvalue of Tan
17、d when the maximum Storque is measured.FIG. 1 Typical Vulcanization CurvesFIG. 2 Example of Torque Responses for an Oscillation CycleD5289 1224. Summary of Test Method4.1 A rubber test piece is contained in a die cavity whichmay be closed or almost closed and maintained at an elevatedtemperature. Th
18、e cavity is formed by two dies, one of which isoscillated through a small rotary amplitude. This action pro-duces a sinusoidal alternating torsional strain in the test pieceand a sinusoidal shear torque which depends on the stiffness(shear modulus) of the rubber compound.4.2 The stiffness of the rub
19、ber test piece increases asvulcanization proceeds. The test is completed when the re-corded torque rises to either an equilibrium or maximum value,or when a predetermined time has elapsed (see Fig. 1).Acurverepresenting the torque at peak strain in one direction of theoscillation cycle is continuous
20、ly recorded as a function of time.5. Significance and Use5.1 This test 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-rub
21、ber compounded in an evaluation formula-tion, and for evaluating various raw materials used in preparing(vulcanizable) rubber compounds.5.3 The test specimen in a rotorless cure meter approachesthe test temperature in a shorter time and there is a bettertemperature distribution in the test specimen
22、due to theelimination of the unheated rotor found in oscillating disk curemeters.5.4 Several manufacturers produce rotorless cure meterswith design differences that may result in different torqueresponses and cure times for each design. Correlations of testresults between cure meters of different de
23、signs should beestablished for each compound tested, and for each set of testconditions.6. Apparatus6.1 Rotorless cure meters of two types can be used. In eachcase, an oscillation of small amplitude is applied to one die.6.1.1 Unsealed Torsion Strain Rotorless Cure MeterThistype of cure meter measur
24、es the torque produced by an angularstrain of constant amplitude in a cavity that is not completelyclosed (see Fig. 3(a).6.1.2 Sealed Torsion Strain Rotorless Cure MeterThistype of cure meter measures the torque produced by an angularstrain of constant amplitude in a cavity that is completelyclosed
25、and sealed (see Fig. 4(a).6.2 Die CavityThe die cavity is formed by two dies. In themeasuring position, the two dies are fixed a specified distanceapart so that the cavity is almost closed (see Fig. 3(b), orclosed and sealed (see Fig. 4(a).6.2.1 The dimensions for typical torsional shear curemetersi
26、nclude biconical-shaped dies having a diameter of 40 6 2mm(1.57 6 0.08 in.), and an angle of separation ranging from 7 to18, depending on the manufacturers design. In the center ofthe dies, a separation equal to 0.5 mm (0.02 in.) plus the diegap should be maintained (see Fig. 3(b) or Fig. 4(b). Manu
27、-facturers guidelines should be followed to determine if thedies have been excessively worn and should be replaced.6.2.2 Die GapThe gap between the edges of the dies inthe closed position shall be between 0.05 and 0.20 mm (0.002to 0.008 in.), preferably 0.1 mm (0.004 in.) for unsealedcavities. For s
28、ealed cavities, no gap should exist at the edges ofthe dies.6.2.3 Die Closing MechanismA pneumatic cylinder orother device shall close the dies and hold them closed duringthe test with a force of not less than 8.0 kN (1820 lbf).6.3 Die Oscillating SystemThe die oscillating systemimparts a torsional
29、oscillating movement to one of the dies, inthe plane of the cavity.6.3.1 The amplitude of the oscillation should be 60.1 to63.0, preferably 60.5 of arc for torsional shear cure meters.6.3.2 The frequency of oscillation should be between 0.5and 2 Hz, preferably 1.7 6 0.1 Hz.6.4 Torque Measuring Syste
30、mA torque measuring systemshall measure the resultant torque.6.4.1 The torque measuring device shall be rigidly coupledto one of the dies and any deformation shall be negligibly smalland shall generate a signal which is proportional to the torque.The total error resulting from zero point error, sens
31、itivity error,linearity, and reproducibility errors shall not exceed 1 % of themeasuring range selected.NOTE 2The elastic deformation of the oscillating and measuringsystem should not be more than 1 % of the oscillating amplitude;otherwise, the curemeter curves must be corrected.6.4.2 The torque rec
32、order device shall be used to record thesignal from the torque measuring device. It shall record the Storque at maximum oscillation as a function of time.6.4.3 The torque recorder device shall be used to record thesignal from the torque measuring device. It shall record thetorque at maximum oscillat
33、ion continuously as a function oftime (see Fig. 1) and shall have a response time for full-scaledeflection on the torque scale of1sorless. The torque shall berecorded with an accuracy of 60.5 % of the range. Torquerecording devices may include analog chart recorders, printers,plotters, or computers.
34、6.5 Torque calibration equipment is required to measure theangular strain amplitude and to calibrate the torque measuringdevice. Examples of calibration equipment are shown in Fig. 5and Fig. 6. The amplitude of oscillation of the device shall bechecked with no test specimen in it.Adisplacement trans
35、ducershall be used to measure the amplitude and torque measure-ments shall be checked against standard masses using a deviceas shown in Fig. 5. An alternate technique shall use a torquestandard.6.5.1 For calibrating torsion shear curemeters, either adisplacement transducer and wire-mass calibration
36、or a torquestandard shall be used.6.5.1.1 A displacement transducer for checking angulardisplacement shall be coupled by a knife-edge bearing incontact with a rod fixed to one of the dies (see Fig. 5). Theforce measuring system shall be checked by loading a wire,attached to the die or block by a pul
37、ley, with masses corre-sponding to the full-scale force being measured. The torqueshall be calculated in this case from the product of the appliedforce and the radius of the die block where the wire is attached.D5289 1236.5.1.2 Torque standard calibration checks the torque mea-surement at the select
38、ed angular displacement by clamping areference steel torsion rod to the oscillating die and the torquemeasuring die of the torsion shear cure meter (see Fig. 6). TheFIG. 3 (a) and (b)Typical Unsealed Torsion Shear Rotorless CuremeterD5289 124reference values for angular displacement and correspondin
39、gtorque have been established by the manufacturer for eachtorque standard.6.6 Temperature Controlling SystemThe method of tem-perature control shall maintain the following process param-eters: heating up time, curing temperature, temperature distri-bution, and reference temperature, which are necess
40、ary forreproducible measurement of the vulcanization curve. Thetemperature control system shall permit the reference tempera-ture to be varied between 110C and 200C with an accuracyof 60.3C or better.6.6.1 Die shall heat up in 1.5 min or less from closure of thedie cavity.6.6.2 Once heating up time
41、hs been completed, die tempera-ture shall not vary by more than 60.3C for the rest of the test.6.6.3 The temperature distribution within the test specimenshall be as uniform as possible. Within the deformation zone,a tolerance of 61C of the average test specimen temperatureshall not be exceeded.6.6.
42、4 The reference temperature is determined by a tempera-ture sensor used for control. The difference between thereference temperature and the average test specimen tempera-ture shall not be more than 2C.6.6.5 Temperature measurement accuracy shall be60.3C for the reference temperature sensor.6.7 Refe
43、rence Test TemperatureThe standard referencetest temperature shall be 160C (320F). Tests may be carriedout at other temperatures if required. Temperatures should beselected in accordance with Practice D1349.7. Sampling7.1 The sample shall be taken from a vulcanizable rubbercompound as required by th
44、e mixing method or other samplinginstructions.FIG. 4 Typical Sealed Torsion Shear Rotorless CuremeterFIG. 5 Displacement Transducer and Wire-Mass CalibrationEquipment for Torsion Shear CuremetersFIG. 6 Typical Torque Standard Calibration Device for TorsionShear CuremetersD5289 1257.2 The sample shal
45、l be homogeneous, in sheeted form, atroom temperature, and as free of air as possible.7.3 The temperature of the sample and its heat history cansignificantly affect test results. For referee testing and fortesting under controlled circumstances, the sample shall beconditions at 23 6 1C (73 6 2F) for
46、 at least 1 h beforetesting.7.4 In production control testing, samples may be testedwithout the conditioning period, but care should be taken tominimize temperature and heat history variations prior totesting.8. Test Specimen8.1 The recommended test specimen volume is between 3and6cm3, depending on
47、the instrument model being used.8.2 The test specimen should be circular, with a diametersmaller than the test chamber of the instrument to be used.8.3 The test specimen is considered to be of proper sizewhen a small bead of rubber compound is extruded uniformlyaround the periphery of the dies as th
48、ey are closed (116 to160 % of the test cavity volume). For an instrument with a testcavity volume of 3.44 cm3, this is achieved when the testspecimen volume is between 4.0 and 5.5 cm3(4.6 to 6.3 g ofrubber compound with a specific gravity of 1.15). Undersizedtest specimens can cause low cavity press
49、ure and low torquereadings. Oversized test specimens cool the dies excessivelyduring the early part of the test period, affecting the vulcani-zation characteristics.9. Procedure9.1 Preparation for TestBring the temperature of bothdies to the reference temperature with the cavity closed.Adjustthe zero of the force or torque measuring device, if necessary.9.2 Loading the Curemeter:9.2.1 Open the dies, unload the previous sample (if neces-sary), place the test piece in the cavity, and close the dieswithin 20
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