1、Designation: D4329 05D4329 13Standard Practice forFluorescent UV Ultraviolet (UV) Lamp Apparatus Exposureof Plastics1This standard is issued under the fixed designation D4329; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the yea
2、r 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.1. Scope*1.1 This practice covers specific procedures and test conditions that are applicable for fluorescent UV exposure of
3、plasticsconducted in accordance with Practices G151 and G154. This practice also covers the preparation of test specimens, the testconditions best suited for plastics, and the evaluation of test results.1.2 The values stated in SI units are to be regarded as standard. The values given in bracketspar
4、entheses are for informationonly.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 and determine the applicability of regulatorylimitatio
5、ns prior to use.NOTE 1This practice is technically similar to ISO 4892-3.2. Referenced Documents2.1 ASTM Standards:2D3980 Practice for Interlaboratory Testing of Paint and Related Materials (Withdrawn 1998)3D5870 Practice for Calculating Property Retention Index of PlasticsE691 Practice for Conducti
6、ng an Interlaboratory Study to Determine the Precision of a Test MethodG113 Terminology Relating to Natural and Artificial Weathering Tests of Nonmetallic MaterialsG141 Guide for Addressing Variability in Exposure Testing of Nonmetallic MaterialsG147 Practice for Conditioning and Handling of Nonmeta
7、llic Materials for Natural and Artificial Weathering TestsG151 Practice for Exposing Nonmetallic Materials in Accelerated Test Devices that Use Laboratory Light SourcesG154 Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Nonmetallic MaterialsG169 Guide for Applicat
8、ion of Basic Statistical Methods to Weathering TestsG177 Tables for Reference Solar Ultraviolet Spectral Distributions: Hemispherical on 37 Tilted Surface2.2 ISO Standard:3ISO 4892-3 PlasticsMethods of Exposure to Laboratory Light SourcesPart 3, Fluorescent UV Lamps2.3 SAE Standard:4SAE J2020 Accele
9、rated Exposure of Automotive Exterior Materials Using a Fluorescent UV and Condensation Apparatus3. Terminology3.1 The definitions in Terminology G113 are applicable to this practice.4. Significance and Use4.1 The ability of a plastic material to resist deterioration of its electrical, mechanical, a
10、nd optical properties caused by exposureto light, heat, and water can be very significant for many applications. This practice is intended to induce property changesassociated with end-use conditions, including the effects of sunlight, ultraviolet solar irradiance, moisture, and heat. The exposure1
11、This practice is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.50 on Durability of Plastics.Current edition approved July 15, 2005July 15, 2013. Published August 2005August 2013. Originally approved in 1984. Last previous edition approv
12、ed in 19992005 asD4329 - 99.D4329 - 05. DOI: 10.1520/D4329-05.10.1520/D4329-13.2 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
13、 the ASTM website.3 Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.10036, http:/www.ansi.org.4 Available from Society of Automotive Engineers SAE International (SAE), 400 Commonwealth Dr., Warrendale, PA 15096-0001.15096-0001, http:/www.sae
14、.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, ASTM recommends that users consult prio
15、r editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.*A Summary of Changes section appears at the end of this standardCopyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 1942
16、8-2959. United States1used in this practice is not intended to simulate the deterioration caused by localized weather phenomena, such as, atmosphericpollution, biological attack, and saltwater exposure. (WarningVariation in results may be expected when operating conditionsare varied within the accep
17、ted limits of this practice. Therefore, no reference to the use of this practice should be made unlessaccompanied by a report prepared in accordance with Section 8 that describes the specific operating conditions used. Refer toPractice G151 for detailed information on the caveats applicable to use o
18、f results obtained in accordance with this practice.)NOTE 2Additional information on sources of variability and on strategies for addressing variability in the design, execution, and data analysis oflaboratory-accelerated exposure tests is found in Guide G141.4.2 Reproducibility of test results betw
19、een laboratories has been shown to be good when the stability of materials is evaluatedin terms of performance ranking compared to other materials or to a control.5,6 Therefore, exposure of a similar material of knownperformance (a control) at the same time as the test materials is strongly recommen
20、ded. It is recommended that at least threereplicates of each material be exposed to allow for statistical evaluation of results.4.3 Test results will depend upon the care that is taken to operate the equipment in accordance with Practice G154. Significantfactors include regulation of line voltage, t
21、emperature of the room in which the device operates, temperature control, and conditionand age of the lamp.5. Apparatus5.1 Use of fluorescent UV apparatus that conforms to the requirements defined in Practices G151 and G154 is required toconform to this practice.5.2 Unless otherwise specified, the s
22、pectral power distribution of the fluorescent UV lamp shall conform to the requirementsin Practice G154 for a UVA 340 lamp. Fig. 1 is a spectral irradiance plot for a typical UVA-340 lamp and benchmark solarradiation.NOTE 3The source of the sunlight ultraviolet solar irradiance data in Fig. 1 is fro
23、mthe Standard G177 standard solar spectrum.5.3 Test ChamberApparatus Location:5 Fischer, R., “Results of Round Robin Studies of Light- andWater-Exposure Standard Practices,” Accelerated and Outdoor Durability Testing of Organic Materials, ASTMSTP 1202, Warren D. Ketola and Douglas Grossman, eds., Am
24、erican Society for Testing and Materials, Philadelphia, 1993.6 Ketola, W., and Fischer, R., “Characterization and Use of Reference Materials in Accelerated Durability Tests,” VAMAS Technical Report No. 30, available from NIST,Gaithersburg, MD.FIG. 1 Representative Spectral Power Distribution of UVA-
25、340 Fluorescent LampsD4329 1325.3.1 Locate the apparatus in an area maintained between 18 and 27C 65 and 80F. Measure ambient temperature at amaximum distance of 150 mm 6 in. from the plane door of the apparatus. (65 and 80F). Control of ambient temperature isparticularly critical when one apparatus
26、 is stacked above another, because the heat generated from the lower unit can interfere withthe operation of the units above.5.3.2 Place the apparatus at least 300 mm from walls or other apparatus. Do not place the apparatus near a heat source suchas an oven.5.3.3 Ventilate the room in which the app
27、aratus is located to remove heat and moisture.6. Test Specimen6.1 The size and shape of specimens to be exposed will be determined by the specifications of the particular test method usedto evaluate the effects of the exposure on the specimens; the test method shall be determined by the parties conc
28、erned. Wherepractical, it is recommended that specimens be sized to fit specimen holders and racks supplied with the exposure apparatus. Unlesssupplied with a specific backing as an integral part of the test, specimens shall be mounted so that only the minimum specimenarea required for support by th
29、e holder shall be covered. This unexposed surface must not be used as part of the test area.6.2 For specimens of insulating materials, such as foams, maximum specimen thickness is 20 mm in order to allow for adequateheat transfer for quickly check the specimens during the condensation period to veri
30、fy that visible condensation is occurring onthe specimens. Perform this visual check once per week at least one hour after the start of condensation.NOTE 4If condensation is not occurring, the most likely cause involves inadequate room-air cooling; (1) the laboratory temperature is too high; (2)cond
31、ensation temperature is set too low, or too close to room temperature; (3) thick specimens of insulating material may be preventing the room-aircooling necessary for condensation. For example, a 25-mm thick wood specimen may exhibit poor condensation with a condensation set point of 40Cand a lab tem
32、perature of 30C; or (4) improper specimen mounting is allowing vapor to escape from the chamber.6.3 To provide rigidity, attach flexible specimens to a backing panel made of aluminum, 0.635 mm 0.025 in.(0.025 in.) thick.Suggested aluminum alloys are 5052, 6061, or 3003.6.4 Seal any holes in specimen
33、s larger than 2 mm and any openings larger than 1 mm around irregularly shaped specimens toprevent loss of water vapor. Attach porous specimens to a solid backing such as aluminum that can act as a vapor barrier.6.5 Unless otherwise specified, expose at least three replicate specimens of each test a
34、nd control material.6.6 Follow the procedures described in Practice G147 for identification, conditioning, and handling of specimens of test,control, and reference materials prior to, during, and after exposure.6.7 Do not mask the face of a specimen for the purpose of showing on one panel the effect
35、s of various exposure times.Misleading results may be obtained by this method, since the masked portion of the specimen is still exposed to temperature andhumidity cycles that in many cases will affect results.6.8 Since the thickness of a specimen may markedly affect the results, thickness of test a
36、nd control specimens shall be within610 % of the nominal dimensions.NOTE 5This is especially important when mechanical properties are being investigated.6.9 Retain a supply of unexposed file specimens of all materials evaluated.6.9.1 When destructive tests are run, ensure that sufficient file specim
37、ens are retained so that the property of interest can bedetermined on unexposed file specimens each time exposed materials are evaluated.6.10 Specimens should not be removed from the exposure apparatus for more than 24 h and then returned for additional tests,since this does not produce the same res
38、ults on all materials as tests run without this type of interruption. When specimens areremoved from the exposure apparatus for 24 h or more and then returned for additional exposure, report the elapsed time as notedin accordance with Section 9.NOTE 6Since the stability of the file specimen may also
39、 be time-dependent, users are cautioned that over prolonged exposure periods, or where smalldifferences in the order of acceptable limits are anticipated, comparison of exposed specimens with the file specimen may not be valid. Instrumentalmeasurements are recommended whenever possible.7. Procedure7
40、.1 When the test and control specimens do not completely fill the specimen racks, fill all empty spaces with blank panels tomaintain the test conditions within the chamber.7.2 Unless otherwise specified, program the device to one of the following test cycles. Operate the device continuously.7.2.1 Cy
41、cle A:D4329 133Typical Irradiance at 340 nm is 0.89 W/(m2 nm)8 h UV with uninsulated black panel temperature controlled at 60 3C8 h UV with uninsulated black panel temperature controlled at 60C4 h condensation with uninsulated black panel temperaturecontrolled at 50 3C4 h condensation with uninsulat
42、ed black panel temperaturecontrolled at 50C(Used for most general applications)7.2.2 Cycle B:Typical Irradiance at 340 nm is 0.77 W/(m2 nm)8 h UV with uninsulated black panel temperature controlled at 70 3C8 h UV with uninsulated black panel temperature controlled at 70C4 h condensation with uninsul
43、ated black panel temperaturecontrolled at 50 3C4 h condensation with uninsulated black panel temperaturecontrolled at 50C(Typically used for automotive applications) Note: Cycle B isequivalent to the exposure test cycle specified in SAE J2020.7.2.3 Cycle C:Typical Irradiance at 340 nm is 0.83 W/(m2
44、nm)8 h UV with uninsulated black panel temperature controlled at 50 3C8 h UV with uninsulated black panel temperature controlled at 50C4 h condensation with uninsulated black panel temperaturecontrolled at 50 3C4 h condensation with uninsulated black panel temperaturecontrolled at 50C(Typically used
45、 for some plastic building products)NOTE 7Unless otherwise specified, operate the apparatus to maintain the operational fluctuations specified in Table 1 for the parameters in CyclesA, B, and C. If the actual operating conditions do not agree with the machine settings after the equipment has stabili
46、zed, discontinue the test and correctthe cause of the disagreement before continuing.7.3 Practice G154 lists several other exposure cycles that are used for fluorescent UV exposures of nonmetallic materials.Obtain mutual agreement between all concerned parties for the specific exposure cycle used.7.
47、4 In order to minimize any effects from temperature or UV light variation, reposition the specimens as follows. Fig. 2 showsa diagram of the specimen repositioning.7.4.1 Reposition the specimens specimen holders horizontally to ensure that each specimen spends the same amount of exposuretime in each
48、 horizontal position within the specimen holder by (1) moving the two extreme right-hand holders to the far left ofthe exposure area, and (2) sliding the remaining holders to the right.7.4.2 Reposition the specimens vertically so that each specimen spends the same amount of exposure time in each ver
49、ticalposition within the specimen holder. For instance, if two specimens are stacked vertically in each holder, then the top and bottomspecimens should switch places halfway through the test. If four specimens are stacked vertically, then the specimens should berepositioned vertically three times during the test.NOTE 8Guidance can be found in ASTM G151 on specimen repositioning or other means of ensuring equal radiant exposure on all specimens orcompensation for differences in irradiance within the exposure chamber.7.5 Water Puri