1、Designation: D 5031 01 (Reapproved 2006)Standard Practice forEnclosed Carbon-Arc Exposure Tests of Paint and RelatedCoatings1This standard is issued under the fixed designation D 5031; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision
2、, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This practice covers the selection of test conditions foraccelerated exposure testing of coatings and r
3、elated products inenclosed carbon arc devices operated according to PracticesG 151 and G 153. This practice also covers the preparation oftest specimens, the test conditions suited for coatings, and theevaluation of test results. Table 1 describes commonly used testconditions.NOTE 1Previous versions
4、 of this practice referenced carbon arcdevices described by Practice G23, which described very specificequipment designs. Practice G23has been withdrawn and replaced byPractice G 151, which describes performance criteria for all exposuredevices that use laboratory light sources, and by Practice G 15
5、3, whichgives requirements for exposing nonmetallic materials in enclosed carbon-arc devices.1.2 This practice does not cover filtered open-flame carbon-arc exposures of paints and related coatings, which is describedin Practice D 822. Another procedure for exposing theseproducts is covered by Pract
6、ice D 3361, in which the speci-mens are subjected to radiation from an unfiltered open-flamecarbon arc that produces shorter wavelengths and higher levelsof short wavelength radiation than filtered open flame orenclosed carbon arcs.NOTE 2Practice D 3361 requires use of open-flame carbon-arc appa-rat
7、us with automatic humidity control.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the use
8、r 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:2D 358 Specification for Wood to Be Used as Panels inWeathering Tests of CoatingsD 523 Test Method for Specular G
9、lossD 609 Practice for Preparation of Cold-Rolled Steel Panelsfor Testing Paint, Varnish, Conversion Coatings, andRelated Coating ProductsD 610 Test Method for Evaluating Degree of Rusting onPainted Steel SurfacesD 659 Method of Evaluating Degree of Chalking of Exte-rior Paints3D 660 Test Method for
10、 Evaluating Degree of Checking ofExterior PaintsD 662 Test Method for Evaluating Degree of Erosion ofExterior PaintsD 714 Test Method for Evaluating Degree of Blistering ofPaintsD 772 Test Method for Evaluating Degree of Flaking (Scal-ing) of Exterior PaintsD 822 Practice for Filtered Open-Flame Car
11、bon-Arc Expo-sures of Paint and Related CoatingsD 823 Practices for Producing Films of Uniform Thicknessof Paint, Varnish, and Related Products on Test PanelsD 1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD 1186 Test Methods for Nondestructive Measurem
12、ent ofDry Film Thickness of Nonmagnetic Coatings Applied toa Ferrous Base3D 1400 Test Method for Nondestructive Measurement ofDry Film Thickness of Nonconductive CoatingsApplied toa Nonferrous Metal Base3D 1729 Practice for Visual Appraisal of Colors and Color1This practice is under the jurisdiction
13、 of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved Nov. 1, 2006. Published November 2006. Originallyapproved in 1989. Last previous edition approved in 2001 as D 5031
14、01.2For 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.3Withdrawn.1Copyright ASTM International, 100 Barr Harbor
15、Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.Differences of Diffusely-Illuminated Opaque MaterialsD 1730 Practices for Preparation of Aluminum andAluminum-Alloy Surfaces for PaintingD 2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Me
16、asured ColorCoordinatesD 2616 Test Method for Evaluation of Visual Color Differ-ence With a Gray ScaleD 3361 Practice for Unfiltered Open-Flame Carbon-ArcExposures of Paint and Related CoatingsD 3980 Practice for Interlaboratory Testing of Paint andRelated Materials3D 4214 Test Methods for Evaluatin
17、g the Degree of Chalk-ing of Exterior Paint FilmsD 5870 Practice for Calculating Property Retention Indexof PlasticsE 691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE 1347 Test Method for Color and Color-Difference Mea-surement by Tristimulus (Filter)
18、ColorimetryG23 Practice for Operating Light-Exposure Apparatus(Carbon-Arc Type) With and Without Water for Exposureof Nonmetallic Materials3G113 Terminology Relating to Natural and ArtificialWeathering Tests of Nonmetallic MaterialsG 141 Guide forAddressing Variability in Exposure Testingof Nonmetal
19、lic MaterialsG 147 Practice for Conditioning and Handling of Nonme-tallic Materials for Natural and Artificial Weathering TestsG 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices that Use Laboratory Light SourcesG 152 Practice for Operating Open Flame CarbonArc LightAppara
20、tus for Exposure of Nonmetallic MaterialsG 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 given in Terminology G113are appli-cable to this p
21、ractice.4. Significance and Use4.1 The ability of a paint or coating to resist deterioration ofits physical and optical properties caused by exposure to light,heat, and water can be very significant for many applications.This practice is intended to induce property changes associatedwith end-use con
22、ditions, including the effects of sunlight,moisture, and heat. The exposure used in this practice is notintended to simulate the deterioration caused by localizedweather phenomena such as atmospheric pollution, biologicalattack, and saltwater exposure.4.2 CautionsVariation in results may be expected
23、 whendifferent operating conditions are used. Therefore, no referenceto the use of this practice shall be made unless accompanied bya report prepared according to Section 10 that describes thespecific operating conditions used. Refer to Practice G 151 fordetailed information on the caveats applicabl
24、e to use of resultsobtained according to this practice.NOTE 3Additional information on sources of variability and onstrategies for addressing variability in the design, execution, and dataanalysis of laboratory accelerated exposure tests is found in Guide G 141.TABLE 1 Test Cycles Commonly Used for
25、Enclosed Carbon-Arc Exposure Testing of Paints and Related CoatingsAUninsulated BlackPanel TemperatureBCycle Number Cycle Description (C) (F) Typical UsesC1 Continuous light102 min light only at 50 6 5%RH18 min light and water sprayDRepeated continuously63 6 2.5 145 6 5 General coatings and historic
26、al conventionE2 18 h continuous light using:102 min light only at 50 6 5%RH18 min light and water spray6 h dark using:95 % relative humidity (no water spray)Repeated continuously63 6 2.524 6 1.5145 6 575 6 3General coatings3 48 min light at 50 6 5%RH12 min light and water sprayRepeated continuously6
27、3 6 2.5 145 6 5 Coatings used in original equipment manufacturing4 4 h light at 50 6 5%RH4 h dark with water sprayRepeated continuously63 6 2.5 145 6 5 Exterior pigmented stains5 12 h light at 50 6 5%RH12 h dark water sprayRepeated continuously63 6 2.5 145 6 5 Exterior wood stains and clears6 8 h li
28、ght at 50 6 5%RH10 h light and water spray6 h dark with water sprayRepeated continuously63 6 2.5 145 6 5 Marine enamelsAThe cycles described are not listed in any order indicating importance, and are not necessarily recommended for the applications listed.BUnless otherwise indicated, black panel tem
29、peratures apply during the light-only portion of the cycle. The equilibrium black panel temperature is obtained without aspray period. For light intervals less than 30 min, the black panel temperature might not reach equilibrium.CTypical uses do not imply that results from exposures of these materia
30、ls according to the cycle described will correlate to those from actual use conditions.DUnless otherwise specified, water spray refers to water sprayed on the exposed surfaces of the test specimens.EHistorical convention has established this as a very commonly used test cycle. This cycle may not ade
31、quately simulate the effects of outdoor exposure.D 5031 01 (2006)24.2.1 The spectral power distribution of light from anenclosed carbon arc is significantly different from that pro-duced in light and water exposure devices using other carbon-arc configurations or other light sources. The type and ra
32、te ofdegradation and the performance rankings produced by expo-sures to enclosed carbon arcs can be much different from thoseproduced by exposures to other types of laboratory lightsources.4.2.2 Interlaboratory comparisons are valid only when alllaboratories use the same type of carbon arc, filters,
33、 andexposure conditions.4.3 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.4,5Therefore, exposure of a similarmaterial of known performance (a control
34、) at the same time asthe test materials is strongly recommended. It is recommendedthat at least three replicates of each material be exposed toallow for statistical evaluation of results.4.4 Test results will depend upon the care that is taken tooperate the equipment according to Practice G 153. Sig
35、nificantfactors include regulation of line voltage, freedom from salt orother deposits from water, temperature and humidity control,and conditions of the electrodes.4.5 All references to exposures in accordance with thispractice must include a complete description of the test cycleused.5. Apparatus5
36、.1 Use enclosed carbon-arc apparatus that conforms to therequirements 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 for the enclosed carbon arc.6. Hazards6.1 Warnin
37、gIn addition to other precautions, never lookdirectly at the carbon arc because UV radiation can damage theeye. Most carbon-arc machines are equipped with door safetyswitches, but users of old equipment must be certain to turn offthe power to the carbon arc before opening the test-chamberdoor.6.2 Th
38、e burning carbon rods used in these devices becomevery hot during use. Make sure to allow at least 15 min for thearcs to cool after the device is turned off before attempting tochange the carbon rods.6.3 Carbon residue and ash are known respiratory irritants.Wear an appropriate high-efficiency dust
39、respirator, gloves, andsafety glasses when handling or changing carbon rods. Makesure to wash any carbon residue from hands or arms prior toeating or drinking.7. Test Specimens7.1 Apply the coating to flat (plane) panels with the sub-strate, method of preparation, method of application, coatingsyste
40、m, film thickness, and method of drying consistent withthe anticipated end use, or as mutually agreed upon betweenthe producer and user.7.2 Panel specifications and methods of preparation includebut are not limited to Practices D 609 or D 1730, or Specifi-cation D 358. Select panel sizes suitable fo
41、r use with theexposure apparatus.7.3 Coat test panels in accordance with Practices D 823,then measure the film thickness in accordance with an appro-priate procedure selected from Test Methods D 1005, D 1186,or D 1400. Nondestructive methods are preferred becausepanels so measured need not be repair
42、ed.7.4 Prior to exposing coated panels in the apparatus, condi-tion them at 23 6 2C (73 6 3F) and 50 6 5 % relativehumidity for one of the following periods in accordance withthe type of coating:Baked coatings 24 hRadiation-cured coatings 24 hAll other coatings 7 days7.4.1 Other procedures for prepa
43、ration of test specimensmay be used if agreed upon by all interested parties.7.5 Mount specimens in holders so that only the minimumspecimen area required for support by the holder is covered.Do not use this covered area of the specimen as part of the testarea.7.6 Unless otherwise specified, expose
44、at least three repli-cate specimens of each test and control material.7.7 Follow the procedures described in Practice G 147 foridentification and conditioning and handling of specimens oftest, control, and reference materials prior to, during, and afterexposure.7.8 Do not mask the face of a specimen
45、 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 the specimen is still exposed to temperatureand humidity cycles that in many cases will affect results.7.9 Retain a supply of unexposed file spe
46、cimens of allmaterials evaluated.7.9.1 When destructive tests are run, it is recommended thata sufficient number of file specimens be retained so that theproperty of interest can be determined on unexposed filespecimens each time exposed materials are evaluated.NOTE 4Since the stability of the file
47、specimen may also be timedependent, users are cautioned that over prolonged 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.Nondestructive instrumental measurements are recommended w
48、heneverpossible.7.10 Specimens should not ordinarily be removed from theexposure apparatus for more than 24 h, then returned foradditional tests, since this does not produce the same results onall materials as tests run without this type of interruption. Whenspecimens are removed from the exposure a
49、pparatus for 24 h ormore, then returned for additional exposure, report the elapsedtime as noted under Section 10.4Fischer, R., “Results of Round-Robin Studies of Light- and Water-ExposureStandard Practices,” Accelerated and Outdoor Durability Testing of OrganicMaterials, ASTM STP 1202, ASTM, 1993.5Ketola, W., and Fischer, R., “Characterization and Use of Reference MaterialsinAccelerated Durability Tests,” VAMAS Technical Report No. 30, NIST, June 1997.D 5031 01 (2006)38. Procedure8.1 Table 1 lists several exposure cycles that are used forenclosed carbon arc exposures of
