ASTM_D_430_-_06_2012.pdf

Designation:D43006(Reapproved 2012)Standard Test Methods forRubber DeteriorationDynamic Fatigue1This standard is issued under the fixed designation D430;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope1.1 These test methods cover testing procedures that esti-mate the ability of soft rubber materials to resist dynamicfatigue.No exact correlation between these test results andservice is given or implied.This is due to the varied nature ofservice conditions.These test procedures do yield data that canbe used for the comparative evaluation of rubber or compositerubber-fabric materials for their ability to resist dynamicfatigue.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses 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 limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D412 Test Methods for Vulcanized Rubber and Thermoplas-tic ElastomersTensionD1349 Practice for RubberStandard Conditions for Test-ingD1682 Test Method for Breaking Load and Elongation ofTextile Fabric(Withdrawn 1992)3D3183 Practice for RubberPreparation of Pieces for TestPurposes from ProductsD3767 Practice for RubberMeasurement of DimensionsD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustries3.Summary of Test Methods3.1 Three test methods are covered,using the followingdifferent types of apparatus:3.1.1 Method AScott Flexing Machine.3.1.2 Method BDeMattia Flexing Machine.3.1.3 Method CE.I.DuPont de Nemours and Co.FlexingMachine.3.1.4 The Scott flexing machine is used principally for testsof Type I,the DeMattia flexing machine for tests of Type II,while the DuPont apparatus is adapted to tests of either Type Ior II,refer to 4.2.4.Significance and Use4.1 Tests for dynamic fatigue are designed to simulate thecontinually repeated distortions received in service by manyrubber articles,such as tires,belts,footwear,and moldedgoods.4.1.1 These distortions may be produced by extension,compressive,and bending forces or combinations thereof.4.1.2 The effect of the distortions is to weaken the rubberuntil surface cracking or rupture occurs.Where rubber iscombined with other flexible materials such as fabric,the effectmay be evidenced by separation at the interface between thematerials,caused either by breaking of the rubber or failure ofthe adhesion or both.4.2 These tests are,therefore,of the following two types:4.2.1 Type ITests designed to produce separation ofrubber-fabric combinations by controlled bending of the speci-mens.4.2.2 Type IITests designed to produce cracking on thesurface of rubber by either repeated bending or extension asmay occur in service.5.Application5.1 Established specifications,practices or methods of testas agreed upon between customer and supplier take precedenceover those contained herein.1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.15 on DegradationTests.Current edition approved May 1,2012.Published May 2012.Originallyapproved in 1935.Last previous edition approved in 2006 as D430 061.DOI:10.1520/D0430-06R12.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Preparation of Test Specimens6.1 Except as may be otherwise specified herein,specimenpreparation shall comply with the requirements of PracticeD3183.7.Test Temperatures and Conditioning7.1 The standard temperature for testing shall be as de-scribed in Practice D1349 for the Standard Laboratory Atmo-sphere 23 6 2C(73.4 6 3.6F).7.2 Controlled temperatures outside the standard range areacceptable and often desirable.Notation of nonstandard testtemperatures shall appear in the report.7.3 Specimens shall be conditioned at the specified tempera-ture for no less than 12 h prior to testing.METHOD A:SCOTT FLEXING MACHINE48.Type of Strain8.1 The Scott flexing machine test method is used to test forply separation in test specimens composed of plies of fabricbonded to rubber compounds(belts,tires,etc.)by controlledbending.9.Test Speci