1、Designation: D 3361 01 (Reapproved 2006)Standard Practice forUnfiltered Open-Flame Carbon-Arc Exposures of Paint andRelated Coatings1This standard is issued under the fixed designation D 3361; the number immediately following the designation indicates the year oforiginal adoption or, in the case of
2、revision, 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 coatin
3、gs and related products inunfiltered open-flame carbon-arc devices conducted accordingto Practice G 151. This practice also covers the preparation oftest specimens, the test conditions suited for coatings, and theevaluation of test results.NOTE 1Previous versions of this practice referenced carbon-a
4、rcdevices 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 Practice G23has been withdrawn and replaced byPractice G 151, which describes performance criteria for all exposuredevices that use laboratory light sources.1.2 This practice covers unfiltered open-flame carbon-arce
5、xposures of paints and related coatings, and covers theexposure cycle that has been commonly referred to as the “dewcycle.” Practice D 822 describes filtered open-flame carbon-arcdevices, and Practice D 5031 describes enclosed carbon-arcexposures. The radiation from an unfiltered open-flame carbonar
6、c produces shorter wavelengths and higher levels of shortwavelength radiation than either filtered open-flame or en-closed carbon arcs.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 est
7、ablish 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 GlossD 609 Practice for Pr
8、eparation 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 Evaluating Degree of Che
9、cking 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 Carbon-Arc Expo-sures of Pai
10、nt 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 Measurement ofDry Film Thickness
11、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 ColorDifferences of Diffusely-Illuminated Opaque MaterialsD 1730 Pract
12、ices for Preparation of Aluminum andAluminum-Alloy Surfaces for PaintingD 2244 Practice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesD 2616 Test Method for Evaluation of Visual Color Differ-ence With a Gray ScaleD 3980 Practice for Interlabora
13、tory Testing of Paint andRelated Materials3D 4214 Test Methods for Evaluating the Degree of Chalk-ing of Exterior Paint FilmsD 5031 Practice for Enclosed Carbon-Arc Exposure Testsof Paint and Related Coatings1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,
14、 Materials, and Applications and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved Nov. 1, 2006. Published December 2006. Originallyapproved in 1974. Last previous edition approved in 2001 as D 3361 01.2For referenced ASTM standards, visit the ASTM we
15、bsite, 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 Drive, PO Box C700, West Conshohocken, PA 19428-2959
16、, United States.D 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) ColorimetryG23 Practice for Opera
17、ting Light-Exposure Apparatus(Carbon-Arc Type) With and Without Water for Exposureof Nonmetallic Materials (Discontinued 2001)3G113 Terminology Relating to Natural and ArtificialWeathering Tests of Nonmetallic MaterialsG 141 Guide forAddressing Variability in Exposure Testingof Nonmetallic Materials
18、G 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 169 Guide forApplication of Basic Statistical Methods toWeathering Tests
19、3. Terminology3.1 The definitions given in Terminology G113are appli-cable to this practice.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 applicat
20、ions.This practice is intended to induce property changes associatedwith end-use conditions, 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, biolo
21、gicalattack, and saltwater exposure.4.2 CautionsVariation in results may be expected 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 condi
22、tions used. Refer to Practice G 151 fordetailed information on the caveats applicable to use of resultsobtained according to this practice.NOTE 2Additional information on sources of variability and onstrategies for addressing variability in the design, execution, and dataanalysis of laboratory accel
23、erated exposure tests is found in Guide G 141.4.2.1 The spectral power distribution of light from anunfiltered open-flame carbon arc is significantly different fromthat produced in light and water exposure devices using othercarbon-arc configurations or other light sources. The type andrate of degra
24、dation and the performance rankings produced byexposures to unfiltered open-flame carbon-arcs can be muchdifferent from that produced by exposures to other types oflaboratory light sources. Typically, exposures conducted ac-cording to this practice will produce degradation faster thansimilar exposur
25、es conducted according to Practice D 822 orD 5031 and may cause different types of degradation.4.2.2 Interlaboratory comparisons are valid only when alllaboratories use the same type of carbon-arc and exposureconditions.4.3 Reproducibility of test results between laboratories hasbeen shown to be goo
26、d 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) at the same time asthe test materials is strongly recommended. It is recommendedthat at least three re
27、plicates 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. Significant factors include regulation ofline voltage, freedom from salt or other deposits from water,temperature and humidity control,
28、 and conditions of theelectrodes.4.5 All references to exposures in accordance with thispractice must include a complete description of the test cycleused.5. Apparatus5.1 Use filtered open-flame carbon-arc apparatus with auto-matic humidity control that conforms to the requirementsdefined in Practic
29、e G 151.5.2 Do not place any filters between the open flame carbonarc and the test specimens.6. Hazards6.1 WarningIn 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 o
30、f old equipment must be certain to turn offthe power to the carbon arc before opening the test-chamberdoor.6.2 This light source generates ozone and nitrous oxides.Vent exhaust from the exposure device to the atmosphere.6.3 The burning carbon rods used in these devices becomevery hot during use. Mak
31、e sure to allow at least 15 min for thearcs to cool after the device is turned off before attempting tochange the carbon rods.6.4 Carbon residue and ash are known respiratory irritants.Wear an appropriate high-efficiency dust respirator, gloves, andsafety glasses when handling or changing carbon rod
32、s. 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, coatingsystem, film thickness, and method of drying consistent withthe anticipated end
33、 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 for use with theexposure apparatus.4Fischer, R., “Results of Round Robin Stu
34、dies 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 199
35、7.D 3361 01 (2006)27.3 Coat test panels in accordance with Test Methods 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 repaired.7.4 Prio
36、r 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 days min7.4.1 Other procedures for preparation
37、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 at leas
38、t 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 for th
39、e 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 specimens
40、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 3Since the stability of the file specime
41、n may also be time-dependent, 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 wheneve
42、rpossible.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 apparat
43、us for 24 h ormore, then returned for additional exposure, report the elapsedtime as noted under Section 10.8. Procedure8.1 Unless otherwise specified, use the following exposurecycle:8.1.1 Sixty min light only with black panel temperaturecontrolled at 63 6 5C (145 6 9F) and relative humiditycontrol
44、led at 50 6 5%.NOTE 4The black panel temperature is for equilibrium conditions.There will be a period immediately after the dark cycle where the blackpanel temperature will be less than the control limits given.8.1.2 Sixty min dark with water spray on the back of testspecimens. During this dark cycl
45、e the chamber air temperatureshall be controlled at 32 6 3C (90 6 5F) and the relativehumidity shall be controlled at 95 6 5%.8.1.3 Adjust the water spray so that the only water on theface of the test specimens is from the dew formation caused bythe chilled water sprayed on the back of the specimens
46、. Thetemperature of the water sprayed on the back of the specimensshall be controlled at 7.2 6 2C (45 6 4F).NOTE 5Each set point and its tolerances given in this sectionrepresent an operational control point for equilibrium conditions at asingle location in the cabinet, which may not necessarily rep
47、resent theuniformity of those conditions throughout the cabinet. ASTM CommitteeG03 is working to refine these tolerances and address the uniformity issue.8.2 Practice D 822 lists other exposure cycles that may beused.8.3 Place test specimens in the device according to themanufacturers recommendation
48、s. It is recommended that allunused spaces in the specimen exposure area be filled withblank metal panels.8.4 If the irradiance uniformity within the exposure areadoes not meet the requirements of Practice G 151 for exposurewithout repositioning, use one of the procedures described inPractice G 151
49、to ensure that specimens receive as uniform aradiant exposure as possible.8.4.1 If specimen repositioning is used, and no repositioningschedule is specified, use the following procedure for specimenrepositioning:8.4.1.1 Once per week, move all holders in the top half ofthe specimen exposure area to the bottom half and move allholders in the bottom half of the exposure area to the top half.Do not reposition the specimens within the holder.NOTE 6Incident energy at the top and bottom of the specimen rack isoften only 70 % of that at the center. This condition requires t
