1、Designation: D 904 99 (Reapproved 2008)Standard Practice forExposure of Adhesive Specimens to Artificial Light1This standard is issued under the fixed designation D 904; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of l
2、ast 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 basic principles and operatingprocedures for ultraviolet (UV) light aging (with or withoutwat
3、er) of adhesive bonded joints having at least one glass ortransparent adherend, using fluorescent UV (see Method A) orxenon-arc light sources (see Method B).1.2 This practice is limited to the apparatus for obtaining,measuring, and controlling the aging conditions, and to theprocedures for exposure.
4、 Sample preparation, strength, testconditions, and evaluation of the results are described in otherASTM test methods or specifications.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly. No other units of measurement are inclu
5、ded in thisstandard.1.4 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 practices and determine the applica-bility of regulatory limitations prior to
6、 use.2. Referenced Documents2.1 ASTM Standards:2D 907 Terminology of AdhesivesG 151 Practice for Exposing Nonmetallic Materials in Ac-celerated Test Devices that Use Laboratory Light SourcesG 154 Practice for Operating Fluorescent Light Apparatusfor UV Exposure of Nonmetallic MaterialsG 155 Practice
7、 for Operating Xenon Arc Light Apparatusfor Exposure of Non-Metallic Materials3. Terminology3.1 DefinitionsMany of the terms in this practice aredefined in Terminology D 907.3.2 Definitions of Terms Specific to This Standard:3.2.1 irradiance, n(1) the rate at which light energy fallson a unit area o
8、f surface (W/m2), or (2) the radiant powerincident upon a unit area of surface.3.2.2 radiant exposure (or light dosage), n(1) the accu-mulated light energy which has fallen on a unit area over time(J/m2), or (2) the irradiance integrated with respect to time.3.2.3 spectral irradiance, nthe distribut
9、ion of irradiancein accordance with wavelength.3.2.3.1 DiscussionSpectral irradiance is usually shown asa curve relating irradiance (ordinate) and light wavelength(abscissa). Because shorter wavelength UV is usually moredamaging than longer wavelength UV, lamps with differentspectral irradiance curv
10、es can cause drastically differentamounts of UV damage, even if they produce the same totalirradiance.3.2.4 spectral power distribution (SPD), nthe amount ofradiation present at each wavelength.3.2.4.1 DiscussionThe SPD can be expressed by power inwatts, irradiance in watts/square metre, or energy i
11、n joules. Theshape of the SPD would be identical in all of these units.Fluorescent lamps are frequently described by relative SPDswhich show the amount of radiation at each wavelength as apercentage of the amount of radiation at the peak wavelength.3.2.5 UV-A, nultraviolet light in the wavelength ba
12、ndbetween 315 and 400 nm.3.2.6 UV-B, nultraviolet light in the wavelength bandbetween 280 and 315 nm.4. Significance and Use4.1 This practice is for determining the effects of UV light,or UV light and water, on adhesive bonded joints undercontrolled but artificial conditions. The results of this pra
13、cticecan be used for comparing the relative durability of severaladhesives in a specific laboratory UV exposure.1This practice is under the jurisdiction of ASTM Committee D14 on Adhesivesand is the direct responsibility of Subcommittee D14.40 on Adhesives for Plastics.Current edition approved April
14、1, 2008. Published April 2008. Originallyapproved in 1946. Last previous edition approved in 2005 as D 904 99 (2005).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
15、 the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.2 This practice is not for determining a forecast of the lifeof an adhesive bond in service. It is only for determining therela
16、tive durability of different adhesives compared to eachother.4.3 The results obtained may vary between the differentlight sources (xenon-arc or fluorescent UV), because of thedifferent spectral-irradiance of the lamps.Adhesives should notbe compared to each other based on their performance underdiff
17、erent types of light sources.4.4 The results obtained may vary when operation condi-tions are varied within the limits of a given method. The resultsmay also vary when exposures are performed on instrumentsmade by different manufacturers. Comparisons between mate-rials must only be made when they ar
18、e tested at the same timein the same instrument. Be sure to accurately report theoperating conditions.4.5 The type and UV transmittance characteristics of thetransparent adherend used can have a significant effect on therate and type of degradation of the adhesives being tested.Comparisons between a
19、dhesives must only be made whentested on transparent adherends of the same type (preferablythe same lot) with the same UV transmission.4.6 This practice is not for determining the effects ofatmospheric pollutants, biological organisms, salt, or freeze/thaw cycles.5. Method AFluorescent UV5.1 Apparat
20、usA fluorescent UV and condensation cham-ber in accordance with Practices G 151 and G 154.5.2 Lamp TypeUse fluorescent UV-A lamps, with a peakemission at 343 nm.NOTE 1UV-A lamps are preferable to UV-B lamps, because UV-Awavelengths can pass through the transparent portion of the test specimenwithout
21、 being absorbed, whereas most of the UV-B wavelengths arefiltered out by the glass.5.2.1 Other fluorescent UV lamps meeting the size andelectrical characteristics in 5.2 may be used by prior agree-ment, provided that the lamp and spectral power distributionare reported in conformance with Section 7.
22、 Use of lamps otherthan those specified in 5.2 may result in significant differencesin test results.5.3 Specimen MountingMount the specimens in the speci-men holders so that the UV passes through the transparentadherend to reach the adhesive joint or so that the joint isexposed to the effects of con
23、densation (if applicable). Use asuitable backing panel to ensure that vapor does not escapefrom the test chamber around the test specimen. When the testspecimens do not completely fill the racks, fill the emptyspaces with blank panels to maintain the test conditions withinthe chamber.5.4 Time/Temper
24、ature CyclesProgram the apparatus toachieve the desired test conditions, as follows:5.4.1 Cycle I4hUVat606 3C followed by 4 hcondensation at 50 6 3C, for applications where the adhesivewill be exposed to moisture.5.4.2 Cycle II24hUVat606 3C with no condensation,for applications where moisture is not
25、 a factor.5.4.3 Other temperatures and time cycles are acceptable, aslong as they are reported in accordance with Section 7.NOTE 2Temperatures are black-panel temperatures measured in thepanel rack.5.5 Operate the apparatus in accordance with PracticesG 151 and G 154.5.6 Expose the specimens for 168
26、 h or multiples thereof,unless a significant change is observed in a shorter time.6. Method BXenon Arc6.1 ApparatusAny xenon arc apparatus in accordancewith Practices G 151 and G 155.6.2 Filter configuration in accordance with Practices G 151and G 155.6.3 Irradiance LevelSet the irradiance level to
27、a levelselected by mutual agreement.6.4 Time/Temperature CyclesProgram the unit for one ofthe following light/spray cycles:6.4.1 Cycle 140 min of light followed by 20 min of lightand specimen spray followed by 60 min of light followed by 60min of dark. During the light cycle operate at a 63 6 3Cblac
28、k-panel temperature and 50 6 5 % relative humidity.During the dark cycle operate at 38 6 2C black-paneltemperature and 95 6 5 % relative humidity.6.4.2 Cycle IIContinuous light without water at a black-panel temperature of 60 6 3C.6.5 Other filters, irradiance levels, relative humidities, tem-peratu
29、res, and time cycles are acceptable, as long as they arereported in accordance with Section 7.6.6 Operate the apparatus in accordance with PracticesG 151 and G 155.6.7 Expose the specimens for either (1) 168 h or multiplesthereof, unless a significant change is observed in a shortertime, or (2) a gi
30、ven amount of radiant exposure.7. Report7.1 Report the following information:7.1.1 Type and model of exposure apparatus and the manu-facturers designation.7.1.2 Type of light source and the manufacturers designa-tion. If a xenon-arc device is used, report the filter combinationand irradiance setting
31、.7.1.3 Specimen temperature setting.7.1.4 Time cycle.7.1.5 Relative humidity if controlled.7.1.6 Number of hours of exposure, or radiant exposure.7.1.7 Type of specimen and property evaluated for changedue to light effects.7.1.8 Type, thickness, and (optionally) UV transmissioncharacteristics of tra
32、nsparent adherend used. If UV transmis-sion is reported, describe how it was measured.7.1.9 Mean and precision of property measured beforeexposure.7.1.10 Mean and precision of property measured afterexposure.7.2 Follow the section on Report contained in PracticesG 151 and G 154 or Practice G 155, as
33、 appropriate.D 904 99 (2008)28. Precision and Bias8.1 It is not practicable to specify the precision and bias ofthis practice because this practice limits itself to the relativedurability of different adhesives compared to each other.9. Keywords9.1 adhesive; artificial light; ultraviolet lightASTM I
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37、Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D 904 99 (2008)3
