ASTM_D_2197_-_16.pdf

Designation:D219716Standard Test Method forAdhesion of Organic Coatings by Scrape Adhesion1This standard is issued under the fixed designation D2197;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.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.Scope1.1 This test method covers the determination of the adhe-sion of organic coatings such as paint,varnish,and lacquerwhen applied to smooth,flat(planar)panel surfaces.1.2 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.3 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 Documents2.1 ASTM Standards:2D609 Practice for Preparation of Cold-Rolled Steel Panelsfor Testing Paint,Varnish,Conversion Coatings,andRelated Coating ProductsD823 Practices for Producing Films of Uniform Thicknessof Paint,Varnish,and Related Products on Test PanelsD1005 Test Method for Measurement of Dry-Film Thick-ness of Organic Coatings Using MicrometersD7091 Practice for Nondestructive Measurement of DryFilm Thickness of Nonmagnetic Coatings Applied toFerrous Metals and Nonmagnetic,Nonconductive Coat-ings Applied to Non-Ferrous MetalsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Summary of Test Method3.1 The materials under test are applied at uniform thicknessto flat panels,usually sheet metal of uniform surface texture.After drying,the adhesion is determined by pushing the panelsbeneath a rounded stylus or loop that is loaded in increasingamounts until the coating is removed from the substratesurface.4.Significance and Use4.1 Coatings to perform satisfactorily must adhere to thesubstrates on which they are applied.This test method has beenfound useful in differentiating the degree of adhesion ofcoatings to substrates.It is most useful in providing relativeratings for a series of coated panels exhibiting significantdifferences in adhesion.4.2 Studies performed in a laboratory using the loop stylusspecified in the previous edition showed meaningful adhesiondata were impossible when loads of 10 to 20 kg were requiredto break the surface of a solvent based coating.The chromeplated loop stylus chattered and skipped across the coatingsurface when loads of this magnitude were required.Similarmeaningless data were obtained when powder coatings weretested that required more than 10 kg to break the surface.Therefore,testing under these conditions is not applicable.5.Apparatus5.1 Application Equipment,as described in Practices D823.5.2 Film-Thickness Measuring Apparatus,as described inTest Method D1005 or Practice D7091.5.3 Balanced Beam,Scrape Adhesion Tester(Figs.1 and 2),consisting of a balanced beam to which is secured a platformfor supporting weights,and a rod at an angle of 45 that holdsthe scraping loop.The rod shall be set so that the scraping loopcontacts test surfaces directly below the weights.The loopshall be 1.6-mm(116-in.)diameter rod,bent into a“U”shapewith an outside radius of 3.25 6 0.05 mm(0.128 6 0.002 in.)and hardened to Rockwell HRC 56 to 58,and shall be a smoothfinish.The loop can be either chromium plated,nickel plated,or heat treated polished steel,as agreed upon between thepurchaser and the supplier.These testers are adjustable toaccommodate flat,metallic,and nonmetallic specimens to1This test method is under the jurisdiction of ASTM Committee D01 on Paintand Related Coatings,Materials,and Applications and is the direct responsibility ofSubcommittee D01.23 on Physical Properties of Applied Paint Films.Current edition approved Dec.1,2016.Published January 2017.Originallyapproved in 1963.Last previous edition approved in 2013 as D2197 13.DOI:10.1520/D2197-16.2For 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 the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1 12-mm(0.5-in.)thick and 100 to 400 mm(4 to 16 in.)wide andlong;the