1、Designation: D1052 09 (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 re
2、vision, 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 me
3、thod 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
4、, 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
5、 an AirOvenD1349 Practice for RubberStandard Temperatures forTestingD3183 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
6、 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.
7、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
8、 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 Pierci
9、ng 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 measu
10、re 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
11、 (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, fabriclaye
12、rs, 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.NOTE 1When specimens of high hardness are being tested, athickness
13、 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. Origi
14、nallyapproved 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 Doc
15、ument Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.2 Unless otherwise specified, the test specimens shall beaged for 24 h at 100C (212F) in accordance with Test MethodD573 and then allowed to remai
16、n 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 holderwit
17、h 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 rubber. The cut
18、 made by thepiercing tool shall be parallel to the width of the test specimen,at a right angle to and across the longitudinal center line of thespecimen at a 62 6 2 mm (2.44 6 0.05 in.) distance from theclamped end.7. Test Temperature7.1 Unless otherwise specified, the test temperature shall be23 6
19、2C (73 6 3.6F).8. Procedure8.1 Measure and record the median thickness of the testspecimen taken at three points across the width at the point ofthe cut in accordance with Procedure A of Practice D3767.8.2 With the holder arm of the flexing machine in ahorizontal position, clamp side by side the tes
20、t specimens ofthe same making sure that the cuts are at the center point of thearc of the rod.8.3 Lower the adjustable top rollers until they just touch thetest specimen and lock in this position by means of the wingnuts, permitting free travel of the test specimens between therollers during the ben
21、ding movement. The position of the testspecimen is shown in Fig. 2.NOTE 2It is recommended that the test specimens be distributedevenly on both sides of the apparatus if only a few are tested.8.4 Start the machine and record the number of cycles bythe use of a counter. Make frequent observations, re
22、cording thenumber of cycles and the increase in cut length measured to thenearest 0.5 mm for the purpose of determining the rate ofincrease in cut length. When observing cut growth, the holderarm shall be at an angle approximately 45 from the vertical.The test shall be continued until the cut length
23、 has increased500 %, that is, until the combined length of the cut and crackhas increased to a total of 15.0 mm (0.60 in.) or when 250kilocycles has been reached with slow cracking samples.8.5 In some cases the cut growth is not in a straight line asa continuation of the cut made by the piercing too
24、l, and“star-shaped” cracking may develop. In this event, the cutgrowth shall be measured as the length of the longest continu-ous crack, regardless of its direction.3The sole source of supply of the piercing tool and apparatus known to thecommittee at this time is CCSI, 221 Beaver St., Akron, OH 443
25、04. If you are awareof alternative suppliers, please provide this information to ASTM InternationalHeadquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee,1which you may attend.FIG. 1 Ross Flexing MachineATest Specimen.BHolder arm.CHolder arm
26、 adjustment.DAdjustable top roller.EFixed lower roller.FSupporting fixed lower roller.GPierced section.H10 mm (0.375 in.) diameter rod over which specimen bends freely througha 90 angle.FIG. 2 Schematic Diagram of Ross Flexing MachineD1052 09 (2014)28.6 When it is necessary to stop operation of the
27、machinetemporarily, the holder arm shall be in a horizontal position, sothat the test specimens remain horizontal while not beingflexed.9. Report9.1 The report shall include the following:9.1.1 Sample identification,9.1.2 Specimen medium thickness,9.1.3 Test temperature if other than 23 6 2C (73 6 3
28、.6F),and9.1.4 The average number of cycles for each 100 % increasein cut growth above the initial pierce of 2.5 mm (0.10 in.) ofthe tested specimens, up to and including 500 %, wherepossible.10. Precision and Bias10.1 A precision and bias statement is not applicable, as thismethod employs qualitativ
29、e ratings, providing only empiricalassessments of the subjected materials.11. Keywords11.1 crack growth; cut growth; cut length; growth rate; Rossflex testmm in.A 6.4 0.01 0.250 0.005B 7.0 0.01 0.275 0.005C 3 0.01 0.125 0.005D 1270.06 50.025E 62 0.03 2.438 0.015F 8 0.01 0.313 0.005G 35 0.02 1.375 0.
30、010H 45 0.02 1.250 0.010I 22 0.02 0.875 0.008J 17 0.02 0.688 0.008K 12 0.02 0.500 0.008L 16 0.02 0.625 0.008M 5 0.01 0.125 0.005N 4 0.01 0.250 0.005P 10 0.01 0.375 0.005Q 11 0.01 0.438 0.005R 41 0.02 1.625 0.010S 6 to 32 screwsT 70 0.03 2.750 0.015U 2.5 0.01 0.10 0.005V 250.02 10.010FIG. 3 Piercing
31、Tool and HolderD1052 09 (2014)3ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof i
32、nfringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this sta
33、ndard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your
34、views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D1052 09 (2014)4
