1、Designation:D224711Standard Practice forTesting Water Resistance of Coatings in 100%RelativeHumidity1This standard is issued under the fixed designation D2247;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.
2、A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 This practice covers the basic principles and opera
3、tingprocedures for testing water resistance of coatings by exposingcoated specimens in an atmosphere maintained at 100%relative humidity so that condensation forms on the testspecimens.1.2 This practice uses the technique of creating a slighttemperature differential within the exposure area to formc
4、ondensation on the coated specimens.As the warmer satu-rated air passes the cooler specimens,water is deposited ontothe specimens in the form of condensation.1.3 This practice places the entire specimen in the exposurearea allowing condensation to form on all surfaces.This makesthis practice suitabl
5、e for flat panels as well as large or 3Dobjects.This practice differs from other methods where con-densation is only formed on the front coating surface,but theback surface is outside the exposure area.Other tests may alsodeposit water droplets on the surface but where the source isnot from condensa
6、tion.NOTE1Alternative practices for testing the water resistance ofcoatings include Practices D870,D1735,and D4585.1.4 This practice is limited to the methods of obtaining,measuring,and controlling the conditions and procedures oftests conducted in 100%relative humidity.It does not specifyspecimen p
7、reparation,or evaluation of results.1.5 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user o
8、f this standard 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:2D609 Practice for Preparation of Cold-Rolled Steel Panelsfor Testing Paint,Varnish,Conversion Coatings,andRelated Co
9、ating ProductsD610 Practice for Evaluating Degree of Rusting on PaintedSteel SurfacesD714 Test Method for Evaluating Degree of Blistering ofPaintsD823 Practices for Producing Films of Uniform Thicknessof Paint,Varnish,and Related Products on Test PanelsD870 Practice for Testing Water Resistance of C
10、oatingsUsing Water ImmersionD1193 Specification for Reagent WaterD1654 Test Method for Evaluation of Painted or CoatedSpecimens Subjected to Corrosive EnvironmentsD1730 PracticesforPreparationof AluminumandAluminum-Alloy Surfaces for PaintingD1735 Practice for Testing Water Resistance of CoatingsUsi
11、ng Water Fog ApparatusD2616 Test Method for Evaluation of Visual Color Differ-ence With a Gray ScaleD3359 Test Methods for Measuring Adhesion by Tape TestD3363 Test Method for Film Hardness by Pencil TestD4541 Test Method for Pull-Off Strength of Coatings UsingPortable Adhesion TestersD4585 Practice
12、 for Testing Water Resistance of CoatingsUsing Controlled Condensation3.Summary of Practice3.1 Coated specimens are placed in an enclosed chambercontaining a heated,saturated mixture of air and water vapor.The temperature of the chamber is usually maintained at 38C(100F).At 100%relative humidity(RH)
13、,a very smalltemperature difference between the specimen and the surround-ing vapor causes the formation of condensation on the speci-mens.The exposure condition is varied by selecting the1This practice is under the jurisdiction of ASTM Committee D01 on Paint andRelated Coatings,Materials,and Applic
14、ations and is the direct responsibility ofSubcommittee D01.27 on Accelerated Testing.Current edition approved Feb.1,2011.Published March 2011.Originallyapproved in 1966.Last previous edition approved in 2010 as D2247 10.DOI:10.1520/D2247-11.2For referenced ASTM standards,visit the ASTM website,www.a
15、stm.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.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C7
16、00,West Conshohocken,PA 19428-2959.United States1 duration of the test.Water permeates the coating at rates thatare dependent upon the characteristics of the coating.Anyeffects such as color change,blistering,loss of adhesion,softening,or embrittlement are observed and reported.4.Significance and Use4.1 Water can cause the degradation of coatings,so knowl-edge of how a coating resists water is helpful for assessing howit will perform in actual service.Failure in tests at 100%relative humidity ma