1、Designation: D 6360 07Standard Practice forEnclosed Carbon-Arc Exposures of Plastics1This standard is issued under the fixed designation D 6360; 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
2、 parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers specific procedures and test condi-tions that are applicable for exposure of plastics in enclosedcarbon-arc devices condu
3、cted in accordance with PracticesG 151 and G 153. This practice also covers the preparation oftest specimens, the test conditions suited for plastics, and theevaluation of test results.1.2 This practice does not cover filtered open-flame carbon-arc exposures of plastics, which are covered in Practic
4、eD 1499. Practice D 5031 describes enclosed carbon-arc expo-sures of paints and related coatings.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
5、practices and determine the applica-bility of regulatory limitations prior to use.NOTE 1There is no known ISO equivalent to this practice.2. Referenced Documents2.1 ASTM Standards:2D 1499 Practice for Filtered Open-Flame Carbon-Arc Ex-posures of PlasticsD 3980 Practice for Interlaboratoy Testing of
6、Paint andRelated Materials3D 5031 Practice for Enclosed Carbon-Arc Exposure Testsof Paint and Related CoatingsD 5870 Practice for Calculating Property Retention Indexof PlasticsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodG113 Terminology Relating
7、to Natural and ArtificialWeathering Tests of Nonmetallic MaterialsG 141 Guide forAddressing Variability in Exposure Testingof Nonmetallic MaterialsG 147 Practice for Conditioning and Handling of Nonme-tallic Materials for Natural and Artificial Weathering TestsG 151 Practice for Exposing Nonmetallic
8、 Materials in Ac-celerated Test Devices that Use Laboratory Light SourcesG 153 Practice for Operating Enclosed Carbon Arc LightApparatus for Exposure of Nonmetallic MaterialsG 169 Guide forApplication of Basic Statistical Methods toWeathering Tests3. Terminology3.1 The definitions in Terminology G11
9、3are applicable tothis practice.4. Significance and Use4.1 The ability of a plastic material to resist deterioration ofits electrical, mechanical, and optical properties caused byexposure to light, heat, and water can be very significant formany applications. This practice is intended to induce prop
10、ertychanges associated with end-use conditions, including theeffects of sunlight, moisture, and heat. The exposure used inthis practice is not intended to simulate the deterioration causedby localized weather phenomena such as atmospheric pollu-tion, biological attack, and saltwater exposure. (Warni
11、ngVariation in results may be expected when operating conditionsare varied within the accepted limits of this practice; therefore,no reference to the use of this practice shall be made unlessaccompanied by a report prepared in accordance with Section9 that describes the specific operating conditions
12、 used. Refer toPractice G 151 for detailed information on the caveats appli-cable to use of results obtained in accordance with thispractice.)NOTE 2Additional information on sources of variability and onstrategies for addressing variability in the design, execution, and dataanalysis of laboratory-ac
13、celerated exposure tests is found in Guide G 141.4.2 Reproducibility of test results between laboratories hasbeen shown to be good when the stability of materials isevaluated in terms of performance ranking compared to othermaterials or to a control; therefore, exposure of a similar1This practice is
14、 under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.50 on Durability of Plastics.Current edition approved March 1, 2007. Published March 2007. Originallyapproved in 1999. Last previous edition approved in 1999 as D 6360 - 99.2For referenced AS
15、TM 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.3Withdrawn.1*A Summary of Changes section appears at the end of this standard.C
16、opyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.material of known performance (a control) at the same time asthe test materials is strongly recommended.4,5It is recom-mended that at least three replicates of each material beexposed to
17、allow for statistical evaluation of results.4.3 Test results will depend upon the care that is taken tooperate the equipment in accordance with Practice G 153.Significant factors include regulation of line voltage, freedomfrom salt or other deposits from water, temperature andhumidity control, and c
18、onditions of the electrodes.5. Apparatus5.1 The enclosed carbon-arc apparatus used shall conformto the requirements defined in Practices G 151 and G 153.5.2 Unless otherwise specified, the spectral power distribu-tion of the enclosed carbon-arc shall conform to the require-ments in Practice G 153 fo
19、r enclosed carbon-arc with borosili-cate glass globes.6. Test Specimen6.1 The size and shape of specimens to be exposed will bedetermined by the specifications of the particular test methodused to evaluate the effects of the exposure on the specimens;therefore, the test method shall be determined by
20、 the partiesconcerned. Where practical, it is recommended that specimensbe sized to fit specimen holders and racks supplied with theexposure apparatus. Unless supplied with a specific backing asan integral part of the test, specimens shall be mounted so thatonly the minimum specimen area required fo
21、r support by theholder shall be covered. This unexposed surface must not beused as part of the test area.6.2 Unless otherwise specified, exposure at least threereplicate specimens of each test and control material.6.3 Follow the procedures described in Practice G 147 foridentification and conditioni
22、ng and handling of specimens oftest, control, and reference materials prior to, during, and afterexposure.6.4 Do not mask the face of a specimen for the purpose ofshowing on one panel the effects of various exposure times.Misleading results may be obtained by this method, since themasked portion of
23、the specimen is still exposed to temperatureand humidity cycles that in many cases will affect results.6.5 Since the thickness of a specimen may markedly affectthe results, thickness of test and control specimens shall bewithin 6 10 % of the nominal dimensions.NOTE 3This is especially important when
24、 mechanical properties arebeing investigated.6.6 Incident energy at the extremes of the specimen expo-sure area in older equipment may be only 70 % of that at thecenter. If the irradiance at any position within the exposure areais less than 90 % of the peak irradiance, follow one of theprocedures ou
25、tlined in Practice G 153 to ensure either equalradiant exposure or compensation for differences in radiantexposure.6.7 Retain a supply of unexposed file specimens of allmaterials evaluated. When destructive tests are run, ensure thatsufficient file specimens are retained so that the property ofinter
26、est can be determined on unexposed file specimens eachtime exposed materials are evaluated.6.8 Specimens should not be removed from the exposureapparatus for more than 24 h and then returned for additionaltests, since this does not produce the same results on allmaterials as tests run without this t
27、ype of interruption. Whenspecimens are removed from the exposure apparatus for 24 h ormore, and then returned for additional exposure, report theelapsed time in accordance with Section 9.NOTE 4Since the stability of the file specimen also may be time-dependent, users are cautioned that over prolonge
28、d exposure periods, orwhere small differences in the order of acceptable limits are anticipated,comparison of exposed specimens with the file specimen may not be valid.Instrumental measurements are recommended whenever possible.7. Procedure7.1 Practice G 153 lists several exposure cycles that areuse
29、d for enclosed carbon-arc exposures of nonmetallic mate-rials. Obtain mutual agreement between all concerned partiesfor the specific exposure cycle used. Additional intervals andmethods of wetting, by spray or condensation, or both, may besubstituted upon mutual agreement among the concernedparties.
30、7.1.1 By historical convention, the following exposure cyclehas been commonly used for plastics:7.1.2 Continuous light with equilibrium uninsulated blackpanel temperature controlled to 63 6 3C (145 6 9F),consisting of the following alternating intervals:7.1.2.1 102 minutes light only followed by 18
31、minutes oflight with water sprayed on the test specimens.7.1.3 Unless otherwise specified, in devices which allow forcontrol of relative humidity, maintain relative humidity at a 506 5 % equilibrium during the light-only interval.NOTE 5The equilibrium black panel temperature is obtained withouta spr
32、ay period. For light intervals less than 30 min the maximum blackpanel temperature may not reach equilibrium.NOTE 6The test cycle described in 7.1.1 (also referred to as the102/18 cycle) may not provide adequate simulation of the effects ofoutdoor exposure.7.2 It is recommended that all unused space
33、s in the speci-men exposure area be filled with blank metal panels.7.3 Water Purity:7.3.1 The purity of water used for specimen spray is veryimportant. Without proper treatment to remove cations, anions,organics, and particularly silica, exposed panels will developspots or stains that may not occur
34、in exterior exposures.7.3.2 Follow the requirements for water purity described inPractice G 151.7.3.3 If specimens are found to have deposits or stains afterexposure in the apparatus, the water purity must be checked todetermine if it meets the requirements of 7.3.2. On someoccasions, exposed specim
35、ens can be contaminated by depositsfrom bacteria that can grow in the purified water used for4Fischer, R., “Results of Round Robin Studies of Light- and Water-ExposureStandard Practices,” Symposium on Accelerated and Outdoor Durability Testing ofOrganic Materials, ASTM STP 1202, ASTM, 1993, p.5Ketol
36、a, W. and Fischer, B., “Characterization and Use of Reference Materialsin Accelerated Durability Tests,” VAMAS Technical Report No. 30, available fromNIST, Gaithersburg, MD.D6360072specimen spray. If bacterial contamination is detected, theentire system used for specimen water spray must be flushedw
37、ith chlorine and thoroughly rinsed prior to resuming expo-sures.7.3.4 The temperature of water used for specimen sprayshould be 16 6 5C (60.8 6 9F).7.3.5 When the preceding water purity requirements are metand there is disagreement between parties on the extent ofproblems caused by stain or deposit,
38、 run referee tests in at leastone other laboratory that can meet the water quality require-ments described in 7.3.7.4 Some tests for lightfastness are run without any speci-men wetting. When this type of test is required, omit the periodwhere water is sprayed on specimens.7.5 It is recommended that
39、a control material be exposed atthe same time as the test specimens for comparison purposes ifperformance comparisons are not being made between the testmaterials themselves. All concerned parties must agree on thecontrol material used.7.6 Identification of any control specimen used shall accom-pany
40、 the report.8. Periods of Exposure and Evaluation of Test Results8.1 In most cases, periodic evaluation of test and controlmaterials is necessary to determine the variation in magnitudeand direction of property change as a function of exposure timeor radiant exposure.8.2 The time or radiant exposure
41、 necessary to produce adefined change in a material property can be used to evaluateor rank the stability of materials. The method is preferred overevaluating materials after an arbitrary exposure time or radiantexposure.8.2.1 Exposure to an arbitrary time or radiant exposure maybe used for the purp
42、ose of a specific test if agreed uponbetween the parties concerned or if required for conformanceto a particular specification. When a single exposure period isused, select a time or radiant exposure that will produce thelargest performance differences between the test materials orbetween the test m
43、aterial and the control material.8.2.2 The minimum exposure time used shall be that nec-essary to produce a substantial change in the property ofinterest for the least stable material being evaluated. Anexposure time that produces a significant change in one type ofmaterial cannot be assumed to be a
44、pplicable to other types ofmaterials.8.2.3 The relation between time to failure in an exposureconducted in accordance with this practice and service life inan outdoor environment requires determination of a validacceleration factor. Do not use arbitrary acceleration factorsrelating time in an exposu
45、re conducted in accordance with thispractice and time in an outdoor environment because they cangive erroneous information. The acceleration factor is material-dependent and is only valid if it is based on data from asufficient number of separate exterior and laboratory-accelerated exposures so that
46、 results used to relate times tofailure in each exposure can be analyzed using statisticalmethods.NOTE 7An example of a statistical analysis using multiple laboratoryand exterior exposures to calculate an acceleration factor is described byJ.A. Simms.6See Practice G 151 for more information and addi
47、tionalcautions about the use of acceleration factors.8.3 After each exposure increment, evaluate or rate changesin exposed test specimens in accordance with applicableASTM test methods.NOTE 8For some materials, changes may continue after the specimenhas been removed from the exposure apparatus. Meas
48、urements (visual orinstrumental) should be made within a standardized time period or asagreed upon between interested parties. The standardized time periodneeds to consider conditioning prior to testing.8.4 Use of results from exposures conducted in accordancewith this practice in specifications:8.4
49、.1 If a standard or specification for general use requires adefinite property level after a specific time or radiant exposurein an exposure test conducted in accordance with this practice,base the specified property level on results from round-robinexperiments run to determine the test reproducibility from theexposure and property measurement procedures. Conduct theseround robins in accordance with Practice E 691 or PracticeD 3980 and include a statistically representative sample of alllaboratories or organizations who would normally conduct theexposure and property measure
