1、Designation: D6695 16Standard Practice forXenon-Arc Exposures of Paint and Related Coatings1This standard is issued under the fixed designation D6695; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A num
2、ber in parentheses indicates the year of last reapproval. Asuperscript epsilon () 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 related products inxenon arc devices
3、 conducted according to Practices G151 andG155. This practice also covers the preparation of testspecimens, the test conditions suited for coatings, and theevaluation of test results.NOTE 1This practice and ISO 16474-2 address the same subjectmatter but differ in technical content.1.2 The values SI
4、units are to be regarded as standard. Thevalues given in parentheses are for information only.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 pra
5、ctices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2D358 Specification for Wood to Be Used as Panels inWeathering Tests of Coatings (Withdrawn 2014)3D523 Test Method for Specular GlossD609 Practice for Preparation of Cold-Rolled S
6、teel Panelsfor Testing Paint, Varnish, Conversion Coatings, andRelated Coating ProductsD610 Practice for Evaluating Degree of Rusting on PaintedSteel SurfacesD659 Method for Evaluating Degree of Chalking of ExteriorPaints (Withdrawn 1990)3D660 Test Method for Evaluating Degree of Checking ofExterior
7、 PaintsD662 Test Method for Evaluating Degree of Erosion ofExterior PaintsD714 Test Method for Evaluating Degree of Blistering ofPaintsD772 Test Method for Evaluating Degree of Flaking (Scal-ing) of Exterior PaintsD823 Practices for Producing Films of Uniform Thicknessof Paint, Varnish, and Related
8、Products on Test PanelsD1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD1186 Test Methods for Nondestructive Measurement ofDry Film Thickness of Nonmagnetic Coatings Applied toa Ferrous Base (Withdrawn 2006)3D1400 Test Method for Nondestructive Measureme
9、nt of DryFilm Thickness of Nonconductive Coatings Applied to aNonferrous Metal Base (Withdrawn 2006)3D1729 Practice for Visual Appraisal of Colors and ColorDifferences of Diffusely-Illuminated Opaque MaterialsD1730 Practices for Preparation of Aluminum andAluminum-Alloy Surfaces for PaintingD2244 Pr
10、actice for Calculation of Color Tolerances andColor Differences from Instrumentally Measured ColorCoordinatesD2616 Test Method for Evaluation of Visual Color Differ-ence With a Gray ScaleD3359 Test Methods for Measuring Adhesion by Tape TestD3980 Practice for Interlaboratory Testing of Paint andRela
11、ted Materials (Withdrawn 1998)3D4214 Test Methods for Evaluating the Degree of Chalkingof Exterior Paint FilmsD5870 Practice for Calculating Property Retention Index ofPlasticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE1347 Test Method for Color
12、and Color-Difference Mea-surement by Tristimulus ColorimetryG113 Terminology Relating to Natural and Artificial Weath-ering Tests of Nonmetallic MaterialsG141 Guide for Addressing Variability in Exposure Testingof Nonmetallic MaterialsG147 Practice for Conditioning and Handling of Nonmetal-lic Mater
13、ials for Natural and Artificial Weathering TestsG151 Practice for Exposing Nonmetallic Materials in Accel-erated Test Devices that Use Laboratory Light Sources1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct re
14、sponsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved May 1, 2016. Published May 2016. Originallyapproved in 2001. Last previous edition approved in 2008 as D6695 08. DOI:10.1520/D6695-16.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact AST
15、M Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document 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
16、C700, West Conshohocken, PA 19428-2959. United States1G155 Practice for Operating Xenon Arc Light Apparatus forExposure of Non-Metallic MaterialsG169 Guide for Application of Basic Statistical Methods toWeathering Tests2.2 ISO Standards:ISO 16474-2 Paints and VarnishesMethods of exposure tolaborator
17、y light sourcesPart 2: Xenon-arc lamps42.3 Society of Automotive Engineers Standards:SAE J2412 Accelerated Exposure of Automotive InteriorTrim Components using a Controlled Irradiance Xenon-Arc Apparatus5SAE J2527 Performance Based Standard for AcceleratedExposure of Automotive Exterior Materials us
18、ing a Con-trolled Irradiance Xenon-Arc Apparatus53. Terminology3.1 The definitions given in Terminology G113 are 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, a
19、nd water can be very significant for many applications.This practice is intended to induce property changes associatedwith end use conditions, including the effects of daylight,moisture, and heat. The exposure used in this practice is notintended to simulate the deterioration caused by localizedweat
20、her phenomena such as atmospheric pollution, biologicalattack, and salt water exposure.4.2 CautionVariation 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 Sec
21、tion 9 that describes thespecific operating conditions used. Refer to Practice G151 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,
22、 execution and dataanalysis of laboratory accelerated exposure tests is found in Guide G141.4.2.1 The spectral power distribution of light from a xenon-arc is significantly different from that produced in light andwater exposure devices using carbon-arc or other light sources.The type and rate of de
23、gradation and the performance rankingsproduced by exposures to xenon-arcs can be much differentfrom those produced by exposures to other types of laboratorylight sources.4.2.2 Interlaboratory comparisons are valid only when alllaboratories use the same light source, filter type, and exposureconditio
24、ns.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.6,7Therefore, exposure of a similarmaterial of known performance (a control) at the same time as
25、the 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 G155. Significantfactors includ
26、e regulation of line voltage, freedom from salts orother deposits from water, temperature and humidity control,and condition and age of the lamp and filters.4.5 All references to exposures in accordance with thispractice must include a complete description of the test cycleused.5. Apparatus5.1 Use x
27、enon-arc apparatus that conforms to the require-ments defined in Practices G151 and G155.5.2 Unless otherwise specified, the spectral power distribu-tion of the xenon-arc shall conform to the requirements inPractice G155 for xenon-arc with daylight filters.6. Test Specimens6.1 Apply the coating to f
28、lat (plane) panels with thesubstrate, method of preparation, method of application, coat-ing system, film thickness, and method of drying consistentwith the anticipated end use, or as mutually agreed uponbetween the producer and user.6.2 Panel specifications and methods of preparation includebut are
29、 not limited to Practices D609, D1730, or SpecificationD358. Select panel sizes suitable for use with the exposureapparatus.6.3 Coat test panels in accordance with Practices D823 andthen measure the film thickness in accordance with an appro-priate procedure selected from Test Methods D1005, D1186,o
30、rD1400. Nondestructive methods are preferred because panelsso measured need not be repaired.6.4 Prior to exposing coated panels in the apparatus, condi-tion them at 23 6 2C (73 6 3F) and 50 6 10 % relativehumidity for one of the following periods in accordance withthe type of coating:Baked coatings
31、24 hRadiation-cured coatings 24 hAll other coatings 7 days min6.4.1 Other procedures for preparation of test specimensmay be used if agreed upon between all interested parties.6.5 Mount specimens in holders so that only the minimumspecimen area required for support by the holder is covered.This unex
32、posed surface must not be used as part of the test4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.6F
33、ischer, R., “Results of Round Robin Studies of Light- and Water-ExposureStandard Practices,” Accelerated and Outdoor Durability Testing of OrganicMaterials, ASTM STP 1202, Warren D. Ketola and Douglas Grossman, Eds, ASTM,1993.7Ketola, W., and Fischer, R. “Characterization and Use of Reference Materi
34、alsin Accelerated Durability Tests,” VAMAS Technical Report No. 30, available fromNIST, June 1997.D6695 162area. In cases where it is necessary to support flexible speci-mens during exposure, attach the flexible specimens to a thinsupporting panel.NOTE 3For supporting flexible specimens, aluminum pa
35、nels that are0.025 in. (0.64 mm) which have been found to be acceptable for manyapplications.6.6 Unless otherwise specified, expose at least three repli-cate specimens of each test and control material.6.6.1 If performance comparisons are not being made be-tween the test materials themselves, it is
36、recommended that acontrol material be exposed simultaneously with experimentalmaterials for determination of relative performance. All con-cerned parties must agree on the control material, if any isused.6.7 Follow the procedures described in Practice G147 foridentification and conditioning and hand
37、ling of specimens oftest, control, and reference materials prior to, during, and afterexposure.6.8 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 the specime
38、n is still exposed to temperatureand humidity cycles that in many cases will affect results.6.9 Retain a supply of unexposed file specimens of allmaterials evaluated.6.9.1 When destructive tests are run, it is recommended thata sufficient number of file specimens be retained so that theproperty of i
39、nterest can be determined on unexposed filespecimens each time exposed materials are evaluated.NOTE 4Since the stability of the file specimen may also be time-dependent, users are cautioned that over prolonged exposure periods, orwhere small differences in the order of acceptable limits are anticipa
40、ted,comparison of exposed specimens with the file specimen may not be valid.Nondestructive instrumental measurements are recommended wheneverpossible.6.10 Specimens should not be removed from the exposureapparatus for more than 24 h then returned for additional tests,since this may not produce the s
41、ame results on all materials astests run without this type of interruption. When specimens areremoved from the exposure apparatus for 24 h or more thenreturned for additional exposure, report the elapsed time asnoted under Section 9.7. Procedure7.1 Table 1 lists several exposure cycles that are used
42、 forxenon-arc exposures of paints and coatings. Obtain agreementbetween all concerned parties for the specific exposure cycleused. Additional intervals and methods of wetting, by spray,condensation, immersion, or combination of these, may besubstituted upon agreement among the concerned parties.NOTE
43、 5Each setpoint and its tolerances found in Table 1 represent anoperational control point for equilibrium conditions at a single location inthe cabinet that may not necessarily represent the uniformity of thoseconditions throughout the cabinet.NOTE 6Spray, condensation, and immersion are different k
44、inds ofmoisture exposures and frequently produce different results.7.1.1 Unless otherwise specified, maintain relative humidityat 50 6 10 % equilibrium during the light-only interval.7.2 If no other cycle is specified, use Cycle No. 1.7.3 Mount test specimens in the device following theplacement and
45、 specimen repositioning procedures described inPractice G155. It is recommended that all unused spaces in thespecimen exposure area be filled with blank metal panels thatare not highly reflective. The blanks used shall be resistant tocorrosion and shall not contaminate the specimens beingexposed.7.4
46、 If the irradiance uniformity does not meet the require-ments of Practice G151, reposition specimens in devicespreferably using the procedure described or, at a minimum, oneof the procedures described in Practice G155.Repositioning of specimens throughout the exposure periodcan minimize variations i
47、n test results for materials that areespecially sensitive to small variations in temperature,humidity, or irradiance.As such, repositioning is always a goodidea and is recommended even if a device meets the irradianceuniformity requirements in Practice G151.It is also recommended to randomly positio
48、n multiplespecimens of each material throughout the specimen rack ortray. By randomly positioning multiple replicate specimens ofone material, the effects of uniformity variations can bereduced.7.4.1 If specimen repositioning is used, and no other repo-sitioning schedule is specified, the following
49、procedure forspecimen repositioning is recommended:7.4.1.1 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 7In older devices, incident energy at the top and bottom of thespecimen rack is often only 70 % of that at the center. This conditionrequires that the procedures described in 7.4 be followed to ensureuniformity of radiant exposure.7.4.1.2 For devices with a planar exposure area, repositio
