ASTM_D_1052_-_09_2014.pdf

Designation:D105209(Reapproved 2014)Standard Test Method forMeasuring Rubber DeteriorationCut Growth Using RossFlexing Apparatus1This standard is issued under the fixed designation D1052;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 This test method covers a test for measuring the cutgrowth in rubber vulcanizates subjected to repeated bendflexing.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:2D573 Test Method for RubberDeterioration in an AirOvenD1349 Practice for RubberStandard Conditions for Test-ingD3183 Practice for RubberPreparation of Pieces for TestPurposes from ProductsD3767 Practice for RubberMeasurement of Dimensions3.Summary of Test Method3.1 A pierced strip test specimen is bent freely over a rod toa 90 angle and the cut length is measured at frequent intervals,to determine the cut growth rate.The cut is initiated by aspecial shaped piercing tool.4.Significance and Use4.1 The test gives an estimate of the ability of rubbervulcanizates to resist crack growth of a pierced specimen whensubjected to bend flexing.4.2 No exact correlation between these test results andservice is implied due to the varied nature of service condi-tions.5.Apparatus5.1 Ross Flexing MachineThe machine,as illustrated inFig.1 and Fig.2,allows one end of the test specimen to beclamped firmly to a holder arm while the pierced end is placedbetween two rollers that must permit a free bending movementof the test specimen during the test.During each cycle,thepierced area of the test specimen is bent freely over a 10-mm(0.4 in.)diameter rod through a 90 angle.The machine shalloperate at 1.7 6 0.08 Hz(100 6 5 cpm).5.2 Piercing Tool and Holder,as shown in Fig.3.5.3 Measuring Instrument,having graduations,or aresolution,capable of measuring the cut length and cut growth,as described in 8.4 and 8.5,to the nearest 0.5 mm(0.02 in.).5.4 Thickness Gage,as described and specified in PracticeD3767,Procedure A,to measure the thickness of the testspecimen as described in 8.1.6.Test Specimens6.1 At least two,preferably three,test specimens of eachsample shall be tested simultaneously.6.1.1 The test specimens shall be 25 6 1 mm(0.98 6 0.04in.)in width,a minimum of 152 mm(5.98 in.)in length,and6.35 6 0.03 mm(0.25 6 0.01 in.)in thickness,and shall be cutfrom a vulcanized sheet 6.35 6 0.03 mm(0.25 6 0.01 in.)inthickness and of suitable dimensions or from finished articlesby cutting and buffing.If obtained from a manufactured article,the piece of rubber shall be free of surface roughness,fabriclayers,and the like,in accordance with the procedure describedin Practice D3183.6.1.2 Unless otherwise specified,the test specimens shall beprepared so that the longitudinal dimension is parallel with thedirection of the milling grain.NOTE1When specimens of high hardness are being tested,athickness other than standard may be used as agreed upon between thesupplier and the consumer.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand is the direct responsibility of Subcommittee D11.15 on Degradation Tests.Current edition approved May 1,2014.Published May 2014.Originallyapproved in 1949.Last previous edition approved in 2009 as D1052 09.DOI:10.1520/D1052-09R14.2For 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 6.2 Unless otherwise specified,the test specimens shall beaged for 24 h at 100C(212F)in accordance with Test MethodD573 and then allowed to remain in the Standard LaboratoryAtmosphere in accordance with Practice D1349,having arelative humidity of 50 6 5%and a temperature of 23 6 2C(73 6 3.6F),for a period of 16 to 96 h.6.3 The test specimens shall be pierced by use of thepiercing tool.3The piercing tool shall be adjusted in the holderwith the cutting edge projecting 7.0 6 0.3 mm(0.275 6 0.010in.)from the base of the holder so that it will pierce completelythrough the test specimens when tapped.Before piercing eachtest specimen,the piercing tool shall be lubricated with a soapsolution that will not react with the r