1、Designation: D1171 161Standard Test Method forRubber DeteriorationSurface Ozone Cracking Outdoors(Triangular Specimens)1This standard is issued under the fixed designation D1171; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、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.1NOTECorrected 7.2.2 editorially in
3、November 2016.1. Scope1.1 This test method permits the estimation of the relativeability of rubber compounds used for applications requiringresistance to outdoor weathering.1.2 This test method is not applicable to materials ordinarilyclassed as hard rubber, but is adaptable to molded or extrudedsof
4、t rubber materials and sponge rubber for use in windowweatherstripping as well as similar automotive applications.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 s
5、afety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D518 Test Method for Rubber DeteriorationSurfaceCracking (Withdrawn 2007)3NOTE 1The procedures in Test Method D518 have been incorporatedas Procedures B1, B2,
6、 and B3 in Test Methods D1149.D1149 Test Methods for Rubber DeteriorationCracking inan Ozone Controlled Environment3. Summary of Test Method3.1 Procedures are given for preparing triangular cross-section specimens, for mounting them in strained conditionaround specified circular mandrels, and for ra
7、ting the effect ofexposure as evidenced by the appearance of surface cracks.The type, time, temperature, and other conditions of exposureare not given but shall be agreed upon by the purchaser and theseller and shall be completely described in the test reports.3.2 Two techniques are described, the e
8、xposure rating andthe quality-retention rating.4. Significance and Use4.1 Molded or extruded rubber products must withstand theeffects of ozone cracking and outdoor weathering for satisfac-tory use. This test enables a simple comparison of performanceto be made under specified test conditions in an
9、outdoor test.No direct correlation between test performance and serviceperformance can be claimed due to the wide range of serviceconditions.5. Apparatus5.1 Mounting MandrelA wood mandrel 50 mm (2 in.) inoutside diameter, suitably coated with spar varnish or a clearlacquer. The mandrel may be suppor
10、ted by any convenientmethod.5.2 Fastening WireEnameled copper wire.6. Test Specimen6.1 The triangular cross-section test specimen shall be amolded, extruded, or sponge section with a continuous skin orsurface layer, 250 mm (10 in.) long, and cured in a straightposition. The cross-sectional dimension
11、s shall be as shown inFig. 1. Duplicate specimens shall be tested.6.2 It is recommended that the manufacturer observe aminimum rest period of 24 h between compound mixing andcompound preparation, and a minimum rest period of12 hbetween compound preparation and curing when preparingspecimens. The fin
12、ish of the specimens shall be as smooth aspossible.1This test method is under the jurisdiction of ASTM Committee D11 on Rubberand Rubber-like Materials and is the direct responsibility of Subcommittee D11.15on Degradation Tests.Current edition approved Jan. 1, 2016. Published January 2016. Originall
13、yapproved in 1951. Last previous edition approved in 2015 as D1171 15. DOI:10.1520/D1171-16E01.2For 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 Documen
14、t 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 States1METHOD AEXPOSURE RATING7. Procedure7.1 Mounting of SpecimensPlace be
15、nch marks on eachspecimen with a crayon, 190 mm (7.5 in.) apart and 32 mm(1.25 in.) from the ends. Form the specimens into a loop byplacing the 19-mm (0.75-in.) sides together and tying securelywith wire at the bench marks. Slip the complete loop over themandrel. Place as many specimens on the mandr
16、els as length ofmandrel will permit.7.2 Exposure of Specimens:7.2.1 Conditioning Period:7.2.1.1 Outdoor ExposureAfter the specimens aremounted allow them to condition for 70 to 72 h at roomtemperature in an ozone free atmosphere. Do not touch thelooped part after mounting until the test is completed
17、.7.2.2 Angle and Direction and Positioning of ExposuresIncline specimens exposed outdoors so that the portion of theloop diametrically opposite the tied ends shall face south at anangle of 45 with the horizontal as shown in Fig. 2.7.2.3 Test Conditions:7.2.3.1 Outdoor ExposureThe type, time, tempera
18、ture,and other essential conditions of exposure shall be agreed uponby the purchaser and the seller.7.3 Rating of Exposed SpecimensWhen the specified ex-posure period is completed, examine the specimens beforeremoval from the mandrel, and evaluate the degree of crackingby comparison with the referen
19、ce standards shown in Fig. 3using a 2-power headgear binocular magnifier or equivalent. Ifthe size of the cracks at 2 magnification is less than thoseshown on one photograph but greater than those shown on thenext lower rating picture, give the lower rating.8. Report8.1 Report the following informat
20、ion:8.1.1 Description of the specimen, giving the identificationnumber of compound and vulcanization data, if known, includ-ing date,8.1.2 Date of start of exposure, and complete informationdescribing conditions of exposure,8.1.3 Rating number of exposed specimens, and8.1.4 If desired, a photograph
21、at 2 magnification.METHOD BQUALITY-RETENTION RATING9. Procedure9.1 If it is desired to apply a quality-retention rating valuebased on three observations of crack rating taken at threesuccessive time intervals of exposure, use the followingprocedure:9.1.1 Prepare the test specimens as described in Se
22、ction 6,and mount and expose as described in 7.1 and 7.2 except thatthe time of exposure shall be six weeks. Other periods ofoutdoor exposure may be used if agreed upon by producer andconsumer. Make the crack rating as described in 7.3 everysecond week or at three equal intervals. This will give thr
23、eeratings.9.1.2 The three crack-growth ratings shall be put together togive a three-digit number and Table 1 then used to find thepercent quality retention. The three-digit crack-growth numberin the crack-growth column corresponds to the quality reten-tion in the right-hand column.10. Report10.1 Rep
24、ort the following information:10.1.1 Description of the specimen, giving the identificationnumber of the compound and date of vulcanization,10.1.2 Date of start of exposure and complete informationdescribing condition of exposure,10.1.3 Crack rating number composed of three digits repre-senting thre
25、e readings taken each two weeks for six weeks ortaken at three equal intervals, and10.1.4 Quality-retention value in percent.11. Precision and Bias11.1 Both the exposure rating and the quality-retentionrating are essentially rank order or qualitative comparisonmethods. Precision as normally expresse
26、d for quantitative-measurement test methods is not directly applicable.12. Keywords12.1 crack growth; cracking; ozone; ozone cracking; surfacecrack; triangular; weatheringFIG. 1 Cross-Sectional Dimension of Test SpecimensFIG. 2 Outdoor Exposure of Test SpecimenD1171 1612ASTM International takes no p
27、osition 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 infringement of such rights, are entirely their own responsib
28、ility.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 standard or for additional standardsand should be addressed to
29、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 views known to the ASTM Committee on Standards, at the addre
30、ss 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), 6
31、10-832-9555 (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 Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 0 Rating 1 Rating 2 Rating 3FIG. 3 Ratings for Weathering Tests of Rubber Compounds (Specimens mounted on mandrel) (2)TABLE 1 Quality Retention RatingCrack Growth Quality Retention, %000 100001 95011 90111 85002 80012 75112 70022 65122 60222 55003 45013 40113 35023 30123 25223 20033 15133 10233 5333 0D1171 1613
