1、Designation: D 870 02Standard Practice forTesting Water Resistance of Coatings Using WaterImmersion1This standard is issued under the fixed designation D 870; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 testing water resistance of coatings by thepartial or compl
3、ete immersion of coated specimens in distilledor de-mineralized water at ambient or elevated temperatures.Although the apparatus and procedure could be employed inimmersion tests using solutions of various materials in water,this practice is limited to tests in water alone.1.2 This practice is limit
4、ed to the methods of obtaining,measuring, and controlling the conditions and procedures ofwater immersion tests. It does not specify specimen prepara-tion, specific test conditions, or evaluation of results.NOTE 1Alternative practices for testing the water resistance ofcoatings include Practices D 1
5、735, D 2247, and D 4585.1.3 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.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 s
6、tandard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:D 609 Practice for Preparation of Cold-Rolled Steel Panelsfor Testing Paint, Varnish, Conversion Coatings, andRelated Coatin
7、g Products2D 610 Test Method for Evaluating Degree of Rusting onPainted Steel Surfaces3D 714 Test Method for Evaluating Degree of Blistering ofPaints2D 823 Practices for Producing Films of Uniform Thicknessof Paint, Varnish, and Related Products on Test Panels2D 1193 Specification for Reagent Water4
8、D 1654 Test Method for Evaluation of Painted or CoatedSpecimens Subjected to Corrosive Environment2D 1730 Practices for Preparation of Aluminum andAluminum-Alloy Surfaces for Painting5D 1735 Practice for Testing Water Resistance of CoatingsUsing Water Fog Apparatus2D 2247 Practice for Testing Water
9、Resistance of Coatings in100 % Relative Humidity2D 2616 Test Method for Evaluation of Visual Color Differ-ence with a Gray Scale2D 3359 Test Methods for Measuring Adhesion by TapeTest2D 3363 Test Method for Film Hardness by Pencil Test2D 4541 Test Method for Pull-Off Strength of CoatingsUsing Portab
10、le Adhesion Testers3D 4585 Practice for Testing Water Resistance of CoatingsUsing Controlled Condensation23. Summary of Practice3.1 Coated specimens are partially or wholly immersed inwater in a container that is resistant to corrosion. The exposureconditions are varied by selecting: (a) the tempera
11、ture of thewater, and (b) the duration of the test. Water permeates thecoating at rates that are dependent upon the characteristics ofthe coating and upon the temperature of the water. Any effectssuch as color change, blistering, loss of adhesion, softening, orembrittlement are observed and reported
12、.4. Significance and Use4.1 Immersion in water can cause the degradation of coat-ings. Knowledge on how a coating resists water immersion ishelpful in predicting its service life. Failure in a waterimmersion test may be caused by a number of factors includinga deficiency in the coating itself, conta
13、mination of the sub-strate, or inadequate surface preparation. The test is thereforeuseful for evaluating coatings alone or complete coatingsystems.4.2 Water immersion tests are used for research and devel-opment of coatings and substrate treatments, specification1This practice is under the jurisdic
14、tion of ASTM Committee D01 on Paint andRelated Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved Aug. 10, 2002. Published October 2002. Originallypublished as D 870 46 T. Last previous edition D 870 97.2Annual
15、 Book of ASTM Standards, Vol 06.01.3Annual Book of ASTM Standards, Vol 06.02.4Annual Book of ASTM Standards, Vol 11.01.5Annual Book of ASTM Standards, Vol 02.05.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.acceptance, and quality
16、control in manufacturing. These teststypically result in a pass or fail determination, but the degree offailure may also be measured. A coating system is consideredto pass if there is no evidence of water-related failure after aspecified period of time.4.3 Results obtained from water immersion tests
17、 in accor-dance with this practice should not be represented as beingequivalent to a period of exposure to water in the naturalenvironment, until the degree of quantitative correlation hasbeen established for the coating or coating system.4.4 Corrosion tests of a scribed coating on a ferrous sub-str
18、ate are impractical in water immersion tests as the corrosionproducts tend to contaminate the water bath. Continuousoverflow of the test tank is sometimes required to maintainconsistent water quality.4.5 The apparatus for the test is relatively inexpensive andcan be as simple as a glass beaker with
19、a stirrer. It is alsopossible to use very large tanks for testing coated pipe or otherlarge coated products.5. Apparatus5.1 Tank Cover, required for some test specifications. Thecover is not to touch the test specimens. The reason for thecover is to help maintain water temperature and water level.5.
20、2 Gabled Cover for TankThe cover should be made ofcorrosion-resistant materials. The cover should not touch anyof the test specimens nor interfere with the air circulationaround the specimens.5.3 System, for circulation of the water with pressurized air,a stirrer, or a pump.5.4 Supports for the Test
21、 Specimens, constructed of non-conductive materials to hold the specimens 30 mm apart and 30mm from the bottom and sidewalls of the tank.NOTE 2The circulating system is for the purpose of exposing all thewater in the tank to room air so the water does not become stratified andoxygen-depleted at the
22、lower levels.6. Test Specimens6.1 This practice does not cover the preparation of testspecimens. The substrate composition and surface preparation,specimen preparation, and the number of specimens should beagreed upon prior to testing.NOTE 3Applicable methods for the preparation of test panels andsu
23、bstrates are given in Practices D 609 and D 1730. Practices D 823covers application techniques for the production of uniform films.6.2 It is recommended that a control specimen of a paintwith known durability be included with each test. Such controlspecimens can provide warning of changes in test se
24、verity in agiven apparatus, and can indicate variations in test severitybetween different apparatuses.6.3 It is recommended that at least two replicate specimensof each different coating be used, to compensate for variationsbetween specimens and variations in test conditions within theapparatus.7. P
25、rocedure7.1 Fill the tank with water to a depth such that the testspecimens are immersed for approximately three-quarters oftheir length. Reagent water conforming to Type IV of Speci-fication D 1193 is suitable for use.7.2 Heat the water to the desired temperature with thecirculating system in opera
26、tion. If no temperature is specified,heat the water to 38 6 2C (100 6 4F). Maintain thetemperature throughout the test.7.3 Place the test specimens in the tank so that the plane ofthe specimens is parallel to the flow of water in the tank.Protect the edges and backs of the specimens from corrosion i
27、fthese surfaces are not to be tested.7.3.1 To control for variability within the apparatus, repo-sition the specimens on a regular basis so that all specimensspend equivalent amounts of time in the various areas of theapparatus (front, back, left, right, and center).7.4 Replace the water if it becom
28、es cloudy or colored.Continuous replacement of the water is permitted. If needed ,add water to maintain original water level.7.5 Conclude the test after a specified period of time, orafter effects from water immersion have been observed.7.6 Wipe the test specimens dry. Rate specimens forchanges in c
29、olor, blistering, etc. Evaluate specimens no lessthan 5 min and no more than 10 min after removal from test,as the effects from water exposure can change within a shorttime. Remove only as many specimens as can be rated withinthe specified time.NOTE 4The 0 to 10 scale described in ASTM STP 5006is pr
30、eferredfor rating. Relevant procedures for evaluating water effects are describedin Test Methods D 610, D 714, D 1654, D 2616, D 3359, D 3363, andD 4541.7.6.1 If possible, rate the specimens again after they havebeen removed from the test for a recovery period long enoughthat moisture absorbed withi
31、n the specimens dries out and thespecimens reach moisture equilibrium with room air. A recov-ery period from 12 to 24 h is generally sufficient. Thepost-recovery rating allows evaluation of the permanent effectsof the exposure as distinct from the transient effects, and isespecially important for ev
32、aluation of color and gloss.8. Report8.1 Report the following information:8.1.1 Sample identification.8.1.2 Results of the evaluation(s).8.1.3 Reference to Practice D 870.8.1.4 Hours of test duration.8.1.5 Test temperature.8.1.6 Brief description of water quality and water replace-ment procedure.8.1
33、.7 Special conditions of test or any deviations in testprocedure.9. Keywords9.1 adhesion; blistering; immersion; resistance-water; rust6Paint and Coating Testing Manual, 14th ed., ASTM, 1995.D870022ASTM International takes no position respecting the validity of any patent rights asserted in connecti
34、on 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 of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible
35、 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 additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consi
36、deration 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 to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Ba
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