1、Designation: D 1828 01 (Reapproved 2007)Standard Practice forAtmospheric Exposure of Adhesive-Bonded Joints andStructures1This standard is issued under the fixed designation D 1828; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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 procedure for the direct expo-sure of adhesive bonded joints and structures to na
3、turalatmospheric environments.1.2 The procedure for sheltered atmospheric exposure, suchas a Stevenson screen (1),2of adhesive-bonded joints andspecimens is the same except for the requirements of facingsouth and measurement of solar radiation.1.3 This practice is limited to the procedure by whichsa
4、mples are exposed and does not cover the tests that may beused to evaluate the effects of atmospheric exposure on theseadhesive-bonded joints and structures. These samples could beany one of several varieties.1.3.1 A complete structure for test,1.3.2 A section of a structure for test,1.3.3 A complet
5、e structure or section with strength obser-vations on specimens cut therefrom,1.3.4 Test specimens themselves, or1.3.5 Any of the above, mounted under stress.1.4 Suitable test methods for evaluation of the effects ofexposure include nondestructive qualitative or quantitativeobservations on the same
6、sample at prescribed intervals, ordestructive tests on separate sets of specimens in accordancewith such tests as Test Method D 1002.NOTE 1See Test Methods D 896 and D 897.1.5 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.6
7、 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 use.2. Referenced Docu
8、ments2.1 ASTM Standards:3D 896 Practice for Resistance ofAdhesive Bonds to Chemi-cal ReagentsD 897 Test Method for Tensile Properties of AdhesiveBondsD 907 Terminology of AdhesivesD 1002 Test Method for Apparent Shear Strength of Single-Lap-Joint Adhesively Bonded Metal Specimens by Ten-sion Loading
9、 (Metal-to-Metal)2.2 ASTM Adjuncts:ASTM Standard Racks and Pipe Frames Blueprints43. Terminology3.1 Definitions:3.1.1 Many terms used in this practice are defined inTerminology D 907.4. Significance and Use4.1 The atmospheric exposure tests described in this prac-tice will evaluate the stability of
10、the adhesive bond only interms of a particular natural atmosphere. Since the atmosphericconditions vary greatly from year to year, these results will not1This practice is under the jurisdiction of ASTM Committee D14 on Adhesivesand is the direct responsibility of Subcommittee D14.40 on Adhesives for
11、 Plastics.Current edition approved Oct. 1, 2007. Published October 2007. Originallyapproved in 1961. Last previous edition approved in 2001 as D 1828 01e1.2The boldface numbers in parentheses refer to the list of references at the end ofthis practice.3For referenced ASTM standards, visit the ASTM we
12、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.4Blueprints of ASTM standard racks and pipe frames may be obtained fromASTM International Headquarters. Order
13、Adjunct No. ADJD1828. Original adjunctproduced in 1957.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.be as reproducible as those derived from laboratory agingprocedures. Considerable research has shown that laboratoryartificial wea
14、thering tests will not give consistently goodcorrelation with outdoor test exposures (2, 3, 4).5. Exposure Sites5.1 The choice of exposure sites is dependent upon theobjective of the particular test program.5.2 In the cases of both metallic and nonmetallic adherends,choose exposure sites to include
15、variations in average tempera-ture (and temperature range), relative humidity, and precipita-tion.6. Apparatus6.1 RacksExpose the sample on racks4which are sopositioned that the exposed surfaces are at an angle of 45 tothe horizontal and facing true south. Exceptions to the directionthat the specime
16、ns face will be permitted in the case of beachexposures, where the specimens usually face parallel to thebeach. Place racks on a supporting frame high enough and soconstructed that there will be no background for a distance ofat least 30 cm (11.8 in.) in any direction from the back ofspecimens mount
17、ed on them. When the frame is positioned onsoil, ensure that the distance between the bottom edge of anyspecimen and the plane of the cleared area great enough toprevent any undesirable effects of grass or plant growth duringthe period of exposure. In case of roof exposure, ensure thatsurrounding wa
18、lls do not shade the specimens or impede the airflow over them. Design the racks that samples or specimenswill be affixed directly to the rack by means of a clampingdevice made of an inert, insulating material that will allowthem to expand or contract with thermal and humidity changes.6.2 Climatolog
19、ical InstrumentsIf detailed information isnecessary, operate instruments suitable for determining aver-age daily temperature, average daily relative humidity, andtotal daily rainfall at or near each of the exposure sites (6, 7, 8).If such instruments are available at some already existinginstallatio
20、n or U. S. Weather Bureau Station in the vicinity ofany site, the records from these are to be considered satisfac-tory (Note 2). If complete characterization of climatologicalconditions is necessary (for transparent adherends, for in-stance), make a record of total daily solar radiation, reportedMJ
21、/m2(langleys) (Note 3).NOTE 2Weather may vary appreciably at two locations only arelatively short distance apart. It must be established to the satisfaction ofthe operator that no significant error will be introduced by usingclimatological data from a site other than the exposure site.NOTE 3A pyrhel
22、iometer in conjunction with a recording potentiom-eter has been found suitable for recording solar radiation (9).7. Test Specimens7.1 In cases where quantitative evaluation is to be made onspecimens cut or machined from the exposed sample, preparethe specimen in accordance with the specific test met
23、hod.Recognize that this is not as severe a test as when the specimenedges have been exposed before evaluation. In cases where itis desired to know the effect of the exposure on exposed edges,expose test specimens rather than samples prior to testing.Where specimens are cut from an exposed sample, re
24、cord therelative location of the specimens in the sample, as effects thatdepend on the distance of the specimen from the exposed edgeof the sample have been noted.7.2 Provide for the number of specimens required by eachtest method plus at least one additional specimen for each testmethod with the nu
25、mber of specimens cut from each sample.The additional specimens serve as spares in the event of ananomalous or faulty specimen.NOTE 4It is recommended that control specimens of a material ofknown behavior be included in each exposure test to serve as at least aqualitative measure of weather variabil
26、ity.7.3 The number of samples is based on a statistical analysisof the test program consistent with the number of specimens ineach sample. The number of specimens for each removalperiod is in accordance with the number required by each testmethod and includes specimens from at least two exposedsampl
27、es.7.4 Evaluation intervals for exposed specimens depend onthe purpose and test duration. Generally, at least three with-drawal intervals are needed to give a reasonable indication ofa materials weathering characteristics (10).8. Procedure8.1 Prior to exposure, condition all samples at the standardc
28、onditions of 23.0 6 1C (73.4 6 1.8F) and 50 6 2 % relativehumidity for not less than 40 h. Then test a control of thenumber of specimens required by the test specifications andrecord the results. Store a second control at standard conditionsof 23.0 6 1C (73.4 6 1.8F) and 50 6 2 % relative humidityto
29、 be tested at the conclusion of the exposure period.8.2 Inscribe the specimens to be exposed with an identifyingnumber, letter, or symbol so that they are readily identifiedafter exposure. Ensure that the identifier does not interfere witheither the exposure or subsequent testing.8.3 Measure the dim
30、ensions and note the appearance of thetest specimens in accordance with the exposure test specifica-tions and record these values.NOTE 5If appearance of the adhesive as observed through theadherend is one of the factors of the test program, develop a system ofuniform observation based on intensity a
31、nd discoloration on an area basis.8.4 Affix the specimens to the exposure racks by means ofinert insulating materials with the edge of the overlap on theexposed face parallel to the ground and facing downward.8.5 Test for a minimum of one year, unless a shorter time isnecessary because of the lack o
32、f durability of the adherends.Where tests of less than one year duration are to be used, startexposure in the spring and continue for the first few weeks ofcool weather. In southern areas, such as Florida, where climaticconditions are more uniform throughout the year, the time ofyear when short-term
33、 exposure is carried out may be lesscritical. In all localities, the longer period of exposure producesmore reliable results.8.6 After exposure, again note and record the appearance ofthe specimens. When performing other than visual appearancetests, condition the specimens for not less than 40 h at
34、23.0 61C (73.4 6 1.8F) and 50 6 2 % relative humidity. Measurethe dimensions, including warpage if any, of the specimensafter the conditioning period just prior to testing.D 1828 01 (2007)28.7 Measure the dimensions, including warpage if any, ofthe stored control specimens, and test these specimens
35、at theconclusion of the exposure period along with the exposedspecimens.9. Report9.1 Report the following:9.1.1 Duration of exposure of each specimen at each site.9.1.2 Original general appearance and original dimensionsof the control and exposed specimens, and properties of theoriginal control spec
36、imens.9.1.3 General appearance, dimensions (including warpage),and properties of the specimens after the exposure and controlstorage periods; and average properties and dimensionalchange for each set of specimens. When changes of less than5 % in any critical dimension of the specimen are observed,ba
37、se the computation of properties on the post-exposuredimensions. When changes of 5 % or more in any criticaldimension have taken place, base the computation of propertiesupon both the original and post-exposure dimensions, andreport two sets of values of the properties.9.1.4 Climatological informati
38、on accumulated during expo-sure. This includes average monthly relative humidity, averagemonthly temperature, and total monthly rainfall at each site foreach month of exposure. When available, report the averagedaily solar radiation for each month at each site and the totalsolar radiation received b
39、y each set of test specimens. Give anyreliable air-pollution data that are available.9.1.5 The location of the exposure sites used including ageneral description of the terrain, the manner in which thespecimens were exposed, a description and the location of theinstruments used to obtain climatologi
40、cal data, and an adequatedescription of the method by which the tests were performed.10. Keywords10.1 adhesive bonded joints; adhesive bonded structures;adhesives; atmospheric exposure; weatheringREFERENCES(1) Middleton, W. E. K., “Meteorological Instruments,” Second Ed.,University of Toronto Press
41、(also Oxford University Press), 1943, p.57.(2) Reinhart, F. W., “Degradation of Plastics,” SPE News (now SPEJournal), Soc. Plastics, Vol 4, September 1948, p. 3.(3) Reinhart, F. W., “Conditioning and Weathering of Adhesives andPlastics,” Symposium on Plastics TestingPresent and Future, ASTMSTP 123,
42、ASTM, 1952, pp. 6170; and Symposium on Conditioningand Weathering, ASTM STP 133, ASTM, 1952, pp. 4251.(4) Reinhart, F. W., “Relation BetweenActual andArtificial Weathering ofOrganic Materials,” Symposium on Some Approaches to Durability inStructures, ASTM STP 236, ASTM, 1958, pp. 5766.(5) Discussion
43、 of ASTM test sites, Proceedings, ASTM, Vol 58, 1958, p.232.(6) “Instructions for Climatological Observers,” Circular B, Tenth Ed., U.S. Government Printing Office, Washington, DC, November 1952.(7) Shelter, Instrument, Medium Standard Cotton Region Type, U. S.Weather Bureau Specification 450 0615,
44、Revised July 1, 1953.(8) Drawing 450.03061a, U. S. Weather Bureau, Washington 25, DC,June, 1951.(9) Hand, I. F., “Pyrheliometers and Pyrheliometric Measurements” U. S.Weather Bureau, Washington, DC 20025, November 1946.(10) Davis, A. and Sims, D. Weathering of Polymers, Elsevier AppliedScience Publi
45、shers, 1983, p. 51.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement
46、of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for
47、 additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known
48、to the ASTM Committee on 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 1828 01 (2007)3
