ASTM_E_2510_-_07_2013.pdf

Designation:E251007(Reapproved 2013)Standard Test Method forTorque Calibration or Conformance of Rheometers1This standard is issued under the fixed designation E2510;the number immediately following 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 describes the calibration or perfor-mance conformance for the torque signal generated by com-mercial or custom-built rheometers.The specific range of thetest depends upon the torque range of the rheometer.1.2 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3 There is no ISO standard equivalent to this test method.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 and health practices and determine the applica-bility of regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesE473 Terminology Relating to Thermal Analysis and Rhe-ologyE617 Specification for Laboratory Weights and PrecisionMass StandardsE1142 Terminology Relating to Thermophysical Properties3.Terminology3.1 Specific technical terms used in this test method aredefined in Terminologies E473 and E1142.These terms includeangular frequency,frequency,loss modulus,rheometer,storagemodulus,strain,stress,viscoelasticity,viscometer,viscometry,and viscosity.3.2 Definitions:3.2.1 torque,nforce applied through a moment arm thatproduces or tends to produce rotation(N m).4.Summary of Test Method4.1 A known force is applied to a rheometer coupling shaftthrough a moment arm to produce a torque.The torque thusapplied is measured and compared to the measured torque.Theratio between indicated and applied torque is used to create acalibration coefficient that may be used in future determina-tions.4.2 The known force generated by suspended precisionmass or masses is transmitted to the rheometer coupling shaftby a line and an appropriate series of pulleys.4.3 Torque is mathematically defined by Eq 1:5 d Fsin(1)where:=torqued=the length of the moment arm(m)F=the applied force(N)=the angle to the moment arm over which the force isapplied()4.3.1 If the force is applied tangentially at right angles(thatis,=90)to the moment arm,then sin=1 and Eq 1 reducesto Eq 2:5 d F(2)4.4 The moment arm in this test method is created byattaching a fixture of known radius to the rheometer couplingshaft in lieu of a geometry,tool or plate.The radius of thefixture is the value of d in Eq 2.4.5 A force is applied to the fixture at a tangent by asuspended mass through a thin wire and a suitable pulleyarrangement(see,for example,Fig.1).4.6 For a mass or masses of known value,the applied forceis given by Eq 3:F 5 M g f(3)where:M=the suspended mass(kg)g=standard acceleration due to gravity(=9.8065 m s2)f=correction factor for local gravity and air buoyancytaken from Table 1(dimensionless)1This test method is under the jurisdiction ofASTM Committee E37 on ThermalMeasurements and is the direct responsibility of Subcommittee E37.08 on Rheol-ogy.Current edition approved March 1,2013.Published April 2013.Originallyapproved in 2007.Last previous edition approved in 2007 as E2510 07.DOI:10.1520/E2510-07R13.2For 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 Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 5.Significance and Use5.1 The test method calibrates or demonstrates conformityof the torque signal of a rheometer at ambient temperature.5.2 A calibration factor thus determined may be used toobtain correct torque values.5.3 This test method may be used in research,development,specification acceptance,and quality control or assurance.6.Apparatus6.1 RheometerThe essential instrumentation required pro-viding the minimum rheological analytical capabilities include:6.1.1 Drive Actuator,to apply torque or angular displace-ment to the specimen in a periodic manner capable of frequen-cies of oscillation from 0.001 to 100 rad/s.This actuator mayalso be capable of providing static torque or displacement onthe specimen.6.1.2 Coupling Shaft,or other means to transmit the torqueor displacement from the motor to the specimen.6.1.3 Geometry or Tool,to fix the specimen between thedrive shaft and a stationary position.6.1.4 Sensor,to measure the torque developed by thespecimen,a position sensor to measure the angular displace-ment of 50 nanoradians of the test specimen,or both.FIG.1 Example of Suspended MassTABLE 1 U