ASTM_D_5179_-_02_2008.pdf

Designation:D517902(Reapproved 2008)Standard Test Method forMeasuring Adhesion of Organic Coatings to PlasticSubstrates by Direct Tensile Testing1This standard is issued under the fixed designation D5179;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.1.Scope1.1 This test method covers the laboratory determination oforganic coating adhesion to plastic substrates by mounting andremoving an aluminum stud from the surface of the coating andmeasuring the force required to break the coating/substratebond with a tensile tester.1.2 This test method requires that the aluminum stud beadhered directly to the surface of a coated,cured panel(Fig.1).1.3 This test method is used to compare the adhesion ofcoatings to various plastic substrates,thus allowing for aquantitative comparison of various coating/substrate combina-tions.1.4 Other tensile test methods are Test Method D4541 andISO 4624(but are not technically equivalent).1.5 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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 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:2D4541 Test Method for Pull-Off Strength of Coatings UsingPortable Adhesion Testers2.2 Other Standard:ISO 4624 Paints and VarnishesPull-off test for adhesion33.Summary of Test Method3.1 An aluminum stud is bonded directly to a coated curedpanel.The adhesive is allowed to cure for 2 h at roomtemperature.The specimen is then subjected to test on a tensiletester equipped with an upper coupling adapter(Fig.2),and arestraining device(Fig.3).3.2 If a coating is to fulfill its function of protecting ordecorating a substrate,it must adhere to it for the expectedservice life.Because the substrate and its surface preparation(or lack of it)has a drastic effect on the adhesion of coatings,a method of evaluation adhesion of a coating to differentsubstrates or surface treatments,or of different coating to thesame substrate and treatment,is of considerable usefulness inthe industry.4.Significance and Use4.1 The pull-off strength(commonly referred to as adhe-sion)of a coating is an important performance property that hasbeen used in specifications.This test method serves as a meansfor uniformly preparing and testing organic coatings on plasticsubstrates.4Further information may be found in Appendix X1.5.Apparatus and Materials5.1 Tensile Tester,commercially available.55.2 Aluminum StudThe shape and dimensions of the studare shown in Fig.1.5.3 Upper Coupling AdaptorThe apparatus is shown inFig.2.The adaptor is 334in.(94 mm)long,114in.(31 mm)1This 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 July 1,2008.Published July 2008.Originally approvedin 1991.Last previous edition approved in 2002 as D5179 02.DOI:10.1520/D5179-02R08.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.4Gray,K.N.,Buckley,S.E.,and Nelson,G.L.,“Accessing MeasurementStandards for Coating Adhesion to Plastics,”Modern Paint and Coatings Journal,Vol 75,No.10,October 1985,p.160.5The sole source of supply of the wooden puritan applicators,in sizes 6 in.(150mm)in length and 0.007 in.(2 mm)in diameter,known to the committee at this timeis Hardwood Products Co.,Guilford,ME 04443.If you are aware of alternativesuppliers,please provide this information to ASTM International.Your commentswill receive careful consideration at a meeting of the responsible technicalcommittee,1which you may attend.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 in diameter at the top,and 1 in.(25 mm)in diameter at thebottom.The hole,indicated by“B,”is used to attach theadaptor to the tensile tester load cell.The hole has a12-in.(13-mm)diameter.The machined opening indicated by“A,”isto receive the head of the aluminum stud.5.4 Restraining DeviceThe apparatus is shown in Fig.3Aand 3 B.The12-in.(13-mm)diameter hole,marked“A,”in the212-in.(63.5-mm)long,114-in.(31-mm