1、Designation: D1171 15D1171 16Standard Test Method forRubber DeteriorationSurface Ozone Cracking Outdoors orChamber (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
2、 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 t
3、est method permits the estimation of the relative ability of rubber compounds used for applications requiring resistanceto outdoor weathering.1.2 This test method is not applicable to materials ordinarily classed as hard rubber, but is adaptable to molded or extruded softrubber materials and sponge
4、rubber for use in window weatherstripping as well as similar automotive applications.1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices an
5、d determine the applicability of regulatorylimitations prior to use. For a specific hazard statement, see Note 1 and 8.1.NOTE 1WarningOzone is a hazardous chemical.2. Referenced Documents2.1 ASTM Standards:2D518 Test Method for Rubber DeteriorationSurface Cracking (Withdrawn 2007)3NOTE 1The procedur
6、es in Test Method D518 have been incorporated as Procedures B1, B2, and B3 in Test Methods D1149.D1149 Test Methods for Rubber DeteriorationCracking in an Ozone Controlled EnvironmentD4575 Test Methods for Rubber DeteriorationReference and Alternative Method(s) for Determining Ozone Level inLaborato
7、ry Test Chambers3. Summary of Test Method3.1 Procedures are given for preparing triangular cross-section specimens, for mounting them in strained condition aroundspecified circular mandrels, and for rating the effect of exposure as evidenced by the appearance of surface cracks. The type, time,temper
8、ature, and other conditions of exposure are not given but shall be agreed upon by the purchaser and the seller and shall becompletely described in the test reports.3.2 Two techniques are described, the exposure rating and the quality-retention rating.4. Significance and Use4.1 Molded or extruded rub
9、ber products must withstand the effects of ozone cracking and outdoor weathering for satisfactoryuse. This test enables a simple comparison of performance to be made under specified test conditions in an outdoor test. No directcorrelation between test performance and service performance can be claim
10、ed due to the wide range of service conditions.5. Apparatus5.1 Mounting MandrelAwood mandrel 50 mm (2 in.) in outside diameter, suitably coated with spar varnish or a clear lacquer.The mandrel may be supported by any convenient method.1 This test method is under the jurisdiction of ASTM Committee D1
11、1 on Rubber and is the direct responsibility of Subcommittee D11.15 on Degradation Tests.Current edition approved July 1, 2015Jan. 1, 2016. Published September 2015January 2016. Originally approved in 1951. Last previous edition approved in 20072015as D1171 99 (2007).D1171 15. DOI: 10.1520/D1171-15.
12、10.1520/D1171-16.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 The last approved version of this historic
13、al standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, AS
14、TM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States15.2 Fa
15、stening WireEnameled copper wire.6. Test Specimen6.1 The triangular cross-section test specimen shall be a molded, extruded, or sponge section with a continuous skin or surfacelayer, 250 mm (10 in.) long, and cured in a straight position. The cross-sectional dimensions shall be as shown in Fig. 1. D
16、uplicatespecimens shall be tested.6.2 It is recommended that the manufacturer observe a minimum rest period of 24 h between compound mixing and compoundpreparation, and a minimum rest period of 12 h between compound preparation and curing when preparing specimens. The finishof the specimens shall be
17、 as smooth as possible.METHOD AEXPOSURE RATING7. Procedure7.1 Mounting of SpecimensPlace bench marks on each specimen with a crayon, 190 mm (7.5 in.) apart and 32 mm (1.25 in.)from the ends. Form the specimens into a loop by placing the 19-mm (0.75-in.) sides together and tying securely with wire at
18、 thebench marks. Slip the complete loop over the mandrel. Place as many specimens on the mandrels as length of mandrel will permit.7.2 Exposure of Specimens:7.2.1 Conditioning Period:7.2.1.1 Outdoor ExposureAfter the specimens are mounted allow them to condition for 70 to 72 h at room temperature in
19、 anozone free atmosphere. Do not touch the looped part after mounting until the test is completed.7.2.2 Angle and Direction and Positioning of Exposures:7.2.2.1 Incline specimens exposed outdoors so that the portion of the loop diametrically opposite the tied ends shall face southat an angle of 45 w
20、ith the horizontal as shown in Fig. 2.7.2.2.2 Ozone Chamber ExposurePosition in the chamber in which ozone is controlled as described in Test Methods D4575.The position of mounted specimens exposed in the ozone test chamber shall be such that there is complete circulation of air aroundthe specimens
21、and the specimens do not touch anything during the necessary handling.7.2.3 Test Conditions:7.2.3.1 Outdoor ExposureThe type, time, temperature, and other essential conditions of exposure shall be agreed upon by thepurchaser and the seller.7.3 Rating of Exposed SpecimensWhen the specified exposure p
22、eriod is completed, examine the specimens before removalfrom the mandrel, and evaluate the degree of cracking by comparison with the reference standards shown in Fig. 3 using a 2-powerheadgear binocular magnifier or equivalent. If the size of the cracks at 2 magnification is less than those shown on
23、 one photographbut greater than those shown on the next lower rating picture, give the lower rating.8. Hazards8.1 WarningOzone is a hazardous substance. Consult and follow all applicable laws, rules, and regulations regardingexposure to ozone.8. Report8.1 Report the following information:8.1.1 Descr
24、iption of the specimen, giving the identification number of compound and vulcanization data, if known, includingdate,8.1.2 Date of start of exposure, and complete information describing conditions of exposure,8.1.3 Rating number of exposed specimens, and8.1.4 If desired, a photograph at 2 magnificat
25、ion.FIG. 1 Cross-Sectional Dimension of Test SpecimensD1171 162METHOD BQUALITY-RETENTION RATING9. Procedure9.1 If it is desired to apply a quality-retention rating value based on three observations of crack rating taken at three successivetime intervals of exposure, use the following procedure:9.1.1
26、 Prepare the test specimens as described in Section 6, and mount and expose as described in 7.1 and 7.2 except that thetime of exposure shall be six weeks. Other periods of outdoor exposure may be used if agreed upon by producer and consumer.Make the crack rating as described in 7.3 every second wee
27、k or at three equal intervals. This will give three ratings.9.1.2 The three crack-growth ratings shall be put together to give a three-digit number and Table 1 then used to find the percentquality retention. The three-digit crack-growth number in the crack-growth column corresponds to the quality re
28、tention in theright-hand column.10. Report10.1 Report the following information:10.1.1 Description of the specimen, giving the identification number of the compound and date of vulcanization,10.1.2 Date of start of exposure and complete information describing condition of exposure,10.1.3 Crack ratin
29、g number composed of three digits representing three readings taken each two weeks for six weeks or takenat three equal intervals, and10.1.4 Quality-retention value in percent.11. Precision and Bias11.1 Both the exposure rating and the quality-retention rating are essentially rank order or qualitati
30、ve comparison methods.Precision as normally expressed for quantitative-measurement test methods is not directly applicable.12. Keywords12.1 crack growth; cracking; ozone; ozone cracking; surface crack; triangular; weatheringFIG. 2 Outdoor Exposure of Test SpecimenD1171 163ASTM International takes no
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32、ibility.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
33、 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 addr
34、ess 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),
35、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 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 164
