ASTM D4585 D4585M-2018 Standard Practice for Testing Water Resistance of Coatings Using Controlled Condensation.pdf

1、Designation: D4585/D4585M 13D4585/D4585M 18Standard Practice forTesting Water Resistance of Coatings Using ControlledCondensation1This standard is issued under the fixed designation D4585/D4585M; the number immediately following the designation indicates theyear of original adoption or, in the case

2、of revision, the year of last revision. A number in parentheses indicates the year of lastreapproval. A superscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This practice covers basic principles and operating procedures for testing water resistance

3、of coatings using controlledcondensation. Condensation is produced by exposing one surface of a coated specimen to a heated, saturated mixture of air andwater vapor, while the reverse side of the specimen is exposed to the cooling effect of room temperature air. This practice is derivedfrom research

4、 of the Cleveland Society for Coatings Technology.21.2 This practice is limited to the methods of obtaining, measuring, and controlling conditions and procedures of controlledcondensation tests. It does not specify specimen preparation, specific test conditions, or evaluation of results.NOTE 1Altern

5、ative practices for testing water resistance of coatings include Practices D870, D1735, and D2247.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in eachsystem may not be exact equivalents; therefore, each system shall be used

6、 independently of the other. Combining values from thetwo systems may result in non-conformance with the standard.1.4 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 s

7、afety safety, health, and healthenvironmental practices and determine theapplicability of regulatory limitations prior to use.1.5 This international standard was developed in accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Dev

8、elopment of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:3D609 Practice for Preparation of Cold-Rolled Steel Panels for Testing Paint, Varnish, Conversion Coatings, and

9、Related CoatingProductsD610 Practice for Evaluating Degree of Rusting on Painted Steel SurfacesD714 Test Method for Evaluating Degree of Blistering of PaintsD823 Practices for Producing Films of Uniform Thickness of Paint, Coatings and Related Products on Test PanelsD870 Practice for Testing Water R

10、esistance of Coatings Using Water ImmersionD1654 Test Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive EnvironmentsD1730 Practices for Preparation of Aluminum and Aluminum-Alloy Surfaces for PaintingD1735 Practice for Testing Water Resistance of Coatings Using Water Fog Ap

11、paratusD2247 Practice for Testing Water Resistance of Coatings in 100 % Relative HumidityD2616 Test Method for Evaluation of Visual Color Difference With a Gray ScaleD3359 Test Methods for Rating Adhesion by Tape TestD3363 Test Method for Film Hardness by Pencil TestD4541 Test Method for Pull-Off St

12、rength of Coatings Using Portable Adhesion Testers1 This practice is under the jurisdiction of ASTM Committee D01 on Paint and Related Coatings, Materials, and Applications and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved June 1, 2013July 1, 2018

13、. Published September 2013July 2018. Originally approved in 1986. Last previous edition approved in 20072013 asD4585 07.D4585 13. DOI: 10.1520/D4585_D4585M-13.10.1520/D4585_D4585M-18.2 Foecking, N. J., “Cleveland Condensing Type Humidity Cabinet,” Offcial Digest, December 1963, Vol 35, No. 467, pp.

14、13181327; and Higgins, W. A., “ClevelandCondensing Type Humidity Cabinet: II,” Offcial Digest, November 1965, Vol 37, No. 490, pp. 13921404.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume

15、 information, refer to the standards Document Summary page on the ASTM website.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 adequat

16、ely depict all changes accurately, ASTM recommends that users consult prior 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 Int

17、ernational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States1G154 Practice for Operating Fluorescent Ultraviolet (UV) Lamp Apparatus for Exposure of Nonmetallic Materials3. Summary of Practice3.1 Water vapor is generated by heating a pan of water at the bottom of t

18、he test chamber. The specimens form the roof or wallsof the test chamber so that the back sides of the specimens are exposed to the cooling effects of room temperature air. The resultingheat transfer causes vapor to condense on the test specimens as liquid water saturated with air.3.2 The temperatur

19、e and amount of condensate forming on the specimens is controlled by the test temperature and the roomtemperature. temperature differential between the test chamber and the room. The test specimens are inclined so that condensateruns off the test surface by gravity and is replaced by fresh condensat

20、e in a continuous process during the condensate cycle.3.3 Exposure conditions are varied by selecting: (a) the temperature of the test, (b) the duration of the test, and (c) periodicdrying of the specimens. Testing may be conducted at temperatures from 38 to 82C 100 to 180F. Any effects such as colo

21、rchange, blistering, loss of adhesion, softening, or embrittlement are observed and reported.4. Significance and Use4.1 Water can cause degradation of coatings, so knowledge of how a coating resists water is helpful in predicting its service life.Failure in a condensation test may be caused by a num

22、ber of factors including a deficiency in the coating itself, contamination ofthe substrate, or inadequate surface preparation. The test is therefore useful for evaluating coatings alone or complete coatingsystems.4.2 Condensation tests of coatings are used for specification acceptance, quality contr

23、ol, and research and development ofcoatings and substrate treatments. These tests usually result in a pass or fail determination but the degree of failure also may bemeasured. A coating system is considered to pass if there is no evidence of water-related failure after a specified period of time.4.3

24、 Results obtained from the use of condensation tests in accordance with this practice should not be represented as beingequivalent to a period of exposure to water in the natural environment, until the degree of quantitative correlation has beenestablished for the coating or coating system.4.4 The t

25、est is usually conducted on metal, plastics, or wood specimens with the coating facing the inside of the chamber.However, it is possible to test the blister resistance of house paintscoatings on wood specimens by mounting the uncoated woodsurface facing the inside of the chamber.4.5 This practice ca

26、n be used for corrosion tests particularly if the specimens are periodically dried. While corrosion productswill drain into the water bath, they are not carried into the vapor that condenses on the test specimens.5. Apparatus5.1 Test Chamber (see Fig. 1 and Fig. 2), consisting of insulated side wall

27、s mounted on a base, test specimen racks attachedto the side walls, a heated water pan, and provisions for controlling and indicating the vapor temperature within the chamber. Vents,approximately 3 to 5 mm 0.10 to 0.20 in. wide, shall be provided to admit room air at the bottom of the test chamber.

28、Locatethe chamber away from air vents and direct drafts.NOTE 2The apparatus described in Practice G154 may be used if the ultraviolet lamps specified in Practice G154 are turned off.5.2 Specimens shall form the roof of the test chamber. If the specimens cannot completely fill all the openings, blank

29、 panelsshall be used. Certain substrates may deform from the heat and moisture. The specimens shall be mounted to eliminate gapsbetween specimens that allow heat and moisture to escape. Various types of tape can be used to seal the gaps that develop whenthe specimen deforms. Specimens shall be incli

30、ned from 15 to 75 from the horizontal and arranged so that condensate is returnedto the water pan without dripping on other specimens.5.3 Water Supply, with water level control.FIG. 1 Controlled Condensation ApparatusD4585/D4585M 1825.4 Water Heater, preferably located under the water pan, controlle

31、d by a thermostat with the sensing element located in thewater.5.5 Thermometer, with the stem extending into the air-water vapor mixture in the test chamber.5.6 Program Timer, Blower, and Air Heater, (optional) fitted to the chamber to provide periods of drying on a fixed schedule.6. Test Specimens6

32、.1 This practice does not cover the preparation of test specimens. The substrate composition and surface preparation, specimenpreparation, and the number of specimens should be agreed upon prior to testing.FIG. 2 Apparatus Cross SectionD4585/D4585M 183NOTE 3Applicable methods for the preparation of

33、test panels and substrates are given in Practice D609 and Practices D1730. Practices D823 coverapplication techniques for the production of uniform films.6.2 Its It is recommended that a control specimen of a paintcoating with known durability be included with each test. Suchcontrol specimens can pr

34、ovide warning of changes in test severity in a given apparatus, and can indicate variations in test severitybetween different apparatuses.6.3 Its It is recommended that at least two replicate specimens of each different coating be used, so as to compensate forvariations between specimens and variati

35、ons in test conditions within the apparatus.6.4 Test specimens should be flat rigid material. Minimum size is 76-mm 3-in. wide and 152-mm 6-in. tall. Maximumthickness is 819 mm 34 in. Materials thicker than 819 mm 34 in. insulate and the condensate does not form on the tested sideof the panel. If th

36、e test panels overshadow the upper shelf, do not put test panels on the upper shelf. Check the samples periodicallyto make sure condensation is occurring.NOTE 4A 3 mm glass plate in place of a sample will work to monitor whether condensation is occurring.7. Procedure7.1 Fill the water pan to a depth

37、 of approximately 25 mm 1 in. with water. The quality of the water in the pan does not affectthe test since the evaporation and condensation process yields distilled water, but the use of tap water can result in the accumulationof residues in the water pan.7.2 Fill all spaces in the specimen holder

38、rack with specimens or corrosion-resistant blank panels. Mount coated metal panelswith the coating to be tested facing the inside of the chamber. Coated wood specimens may be mounted in the same way.7.2.1 Blister tests to simulate the effects of water vapor migration from inside a frame house are mo

39、unted with the uncoatedside of the wood specimen facing the inside of the test chamber.7.2.2 Close all cracksgaps between specimens and all holes in specimens, to prevent water vapor loss and local temperaturevariation. Condensate usually seals cracksgaps or holes smaller than 1 mm 0.04 in., but lar

40、ger openings must be closed with tapeor metal strips.tape, metal strips, or other suitable gap-filling materials.7.3 Adjust the thermostat to maintain the desired temperature of the saturated air and water vapor mixture. Vapor temperaturesof 38, 49, or 60C 100, 120, or 140F are suggested. Other temp

41、eratures may be used provided that the temperature is reportedin conformance with Section 8. To ensure adequate condensation, maintain at least a 11C 20F temperature differential betweenthe room and the vapor.7.4 Operate the chamber continuously unless otherwise specified or agreed. The removal of s

42、pecimens for inspections duringoperation is permitted. When removing a specimen for inspection, replace it with a blank so that the test conditions are not altered.7.5 Cyclic operation with alternating periods of condensation and drying may be used.Automatic drying requires the apparatusdescribed in

43、 5.6. For manual drying of specimens, remove them from the apparatus. Drying periods should be of at least 4 hlong.long are recommended.7.6 To control for variability within the apparatus, reposition the specimens on a regular basis so that all specimens spendequivalent amounts of time in the variou

44、s areas of the apparatus (top, bottom, left, right, and center).7.7 Conclude the test after a specified period of time or after effects from exposure to water are noted.7.8 Remove specimens at the conclusion of the test. Do not leave the specimens in the apparatus at the conclusion of the testas the

45、 specimens can remain wet for hours, or even days, when the apparatus is turned off.7.9 Wipe the test specimens dry. Rate specimens for changes in color, blistering, etc. Evaluate specimens no less than 5 minand no more than 10 min after removal from test, as the effects from water exposure can chan

46、ge within a short time. Remove onlyas many specimens as can be rated within the specified time.NOTE 5 Relevant procedures for evaluating water effects are described in Test Methods D610 and D2616, and Test Methods D714, D1654, D2616,D3359, D3363, and D4541.7.9.1 If possible, rate the specimens again

47、 after they have been removed from the test for a recovery period long enough thatmoisture absorbed within the specimen dries out and the specimens reach moisture equilibrium with room air. A recovery periodfrom 12 to 24 h is generally sufficient. The post-recovery rating allows evaluation of the pe

48、rmanent effects of the exposure asdistinct from the transient effects, and is especially important for evaluation 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 D4585.8.1.4 Hours of test dura

49、tion.8.1.5 Description of any cyclic operations.D4585/D4585M 1848.1.6 Condensation temperature.8.1.7 Special conditions of test or any deviations in test procedure.9. Keywords9.1 adhesion; blistering; condensation; humidity; resistance-water; rustSUMMARY OF CHANGESCommittee D01 has identified the location of selected changes to this standard since the last issue(D4585D4585/D4585M-07)-13) that may impact the use of this standard. (Approved JuneJuly 1, 2013.)2018.)(1) Revised sentence 5.2 by changing “should” to “shall” and “avoid” to “