1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 4628-8:2012Paints and varnishes Evaluation of degradation of coatings Designation of quantity and size of defects, and of intensity of uniform changes in appearancePart
2、 8: Assessment of degree of delamination and corrosion around a scribe or other artificial defectBS EN ISO 4628-8:2012 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO4628-8:2012. It supersedes BS EN ISO 4628-8:2005 which iswithdrawn.The UK participation in i
3、ts preparation was entrusted to TechnicalCommittee STI/10, Test methods for paints.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its co
4、rrectapplication. The British Standards Institution 2013. Published by BSI StandardsLimited 2013ISBN 978 0 580 68300 8ICS 87.040Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy
5、Committee on 28 February 2013.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 4628-8 November 2012 ICS 87.040 Supersedes EN ISO 4628-8:2005English Version Paints and varnishes - Evaluation of degradation of coatings - Designation of quant
6、ity and size of defects, and of intensity of uniform changes in appearance - Part 8: Assessment of degree of delamination and corrosion around a scribe or other artificial defect (ISO 4628-8:2012) Peintures et vernis - valuation de la dgradation des revtements - Dsignation de la quantit et de la dim
7、ension des dfauts, et de lintensit des changements uniformes daspect - Partie 8: valuation du degr de dcollement et de corrosion autour dune rayure ou dun autre dfaut artificiel (ISO 4628-8:2012) Beschichtungsstoffe - Beurteilung von Beschichtungsschden - Beurteilung der Menge und der Gre von Schden
8、 und der Intensitt von gleichmigen Vernderungen im Aussehen - Teil 8: Bewertung der von einem Ritz oder einer anderen knstlichen Verletzung ausgehenden Enthaftung und Korrosion (ISO 4628-8:2012)This European Standard was approved by CEN on 5 October 2012. CEN members are bound to comply with the CEN
9、/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC Management Cen
10、tre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same status as th
11、e official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Nether
12、lands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2012 CEN All rights of exploi
13、tation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 4628-8:2012: EBS EN ISO 4628-8:2012EN ISO 4628-8:2012 (E) 3 Foreword This document (EN ISO 4628-8:2012) has been prepared by Technical Committee ISO/TC 35 “Paints and varnishes“ in collaboration with Tec
14、hnical Committee CEN/TC 139 “Paints and varnishes” the secretariat of which is held by DIN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2013, and conflicting national standards shall be wi
15、thdrawn at the latest by May 2013. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 4628-8:2005. Accord
16、ing to the CEN/CENELEC Internal Regulations, the national standards organisations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
17、Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 4628-8:2012 has been approved by CEN as a EN ISO 4628-8:20
18、12 without any modification. BS EN ISO 4628-8:2012ISO 4628-8:2012(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical
19、 committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with
20、 the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.The main task of technical committees is to prepare International Standards. Draft Internat
21、ional Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.Attention is drawn to the possibility that some of the elements of this document may be
22、the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 4628-8 was prepared by Technical Committee ISO/TC 35, Paints and varnishes, Subcommittee SC 9, General test methods for paints and varnishes.This second edition cancels and replaces the
23、first edition (ISO 4628-8:2005). For this revision:a) the use of measurement and calculation to determine delamination and corrosion is preferred over the use of pictorial standards;b) artificial defects with shape other than a linear scribe mark are introduced.ISO 4628 consists of the following par
24、ts, under the general title Paints and varnishes Evaluation of degradation of coatings Designation of quantity and size of defects, and of intensity of uniform changes in appearance: Part 1: General introduction and designation system Part 2: Assessment of degree of blistering Part 3: Assessment of
25、degree of rusting Part 4: Assessment of degree of cracking Part 5: Assessment of degree of flaking Part 6: Assessment of degree of chalking by tape method Part 7: Assessment of degree of chalking by velvet method Part 8: Assessment of degree of delamination and corrosion around a scribe or other art
26、ificial defect Part 10: Assessment of degree of filiform corrosion ISO 2012 All rights reserved iiiBS EN ISO 4628-8:2012ISO 4628-8:2012(E)IntroductionISO 4628-11defines a system for designating the quantity and size of defects and the intensity of uniform changes in appearance of coatings and outlin
27、es the general principles of the system. This system is intended to be used, in particular, for defects caused by ageing and weathering, and for uniform changes such as colour changes, for example yellowing.The other parts of ISO 4628 provide pictorial standards or other means for evaluating particu
28、lar types of defect. As far as possible, already existing evaluation schemes have been used as the basis.After exposure of a coated test panel with a scribe or other artificial defect in a corrosive environment, one, or a combination of both of, the following phenomena can occur around the scribe or
29、 other artificial defect: delamination; corrosion.Delamination and corrosion around the scribe or other artificial defect are evaluated separately to provide more detailed information about the performance of a coating system in corrosive environments.In addition to the procedure specified in this p
30、art of ISO 4628, assessments of delamination and corrosion around the scribe or other artificial defect may be carried out using optical image processing.Rating of other defects is described in other parts of ISO 4628.iv ISO 2012 All rights reservedBS EN ISO 4628-8:2012Paints and varnishes Evaluatio
31、n of degradation of coatings Designation of quantity and size of defects, and of intensity of uniform changes in appearance Part 8: Assessment of degree of delamination and corrosion around a scribe or other artificial defect1 ScopeThis part of ISO 4628 specifies a method for assessing delamination
32、and corrosion around a scribe or other artificial defect on a coated panel or other coated test specimen, caused by a corrosive environment.This part of ISO 4628 does not cover evaluation of pitting corrosion or pit depth.NOTE 1 Examples of corrosive environments are artificial atmospheres such as s
33、alt spray, as used in the test method specified in ISO 9227,7and sea water immersion as used in the test method specified in ISO 15711.8Natural environments can also be used.NOTE 2 The extent of other defects can also be determined at the same time as delamination and corrosion. Methods are given as
34、 follows: blistering in accordance with ISO 4628-2;2 rusting in accordance with ISO 4628-3;3 cracking in accordance with ISO 4628-4;4 flaking in accordance with ISO 4628-5;5 filiform corrosion in accordance with ISO 4628-10.62 Normative referencesThe following referenced documents are indispensable
35、for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 3270, Paints and varnishes and their raw materials Temperatures and humidities for conditioning and
36、 testing3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1holidayabsence of a paint film from certain areas of a coated substrate3.2artificial defectholiday through a coating, deliberately introduced in order to expose the underlying metal substra
37、te prior to exposure to a corrosive environmentINTERNATIONAL STANDARD ISO 4628-8:2012(E) ISO 2012 All rights reserved 1BS EN ISO 4628-8:2012ISO 4628-8:2012(E)3.3circular defectcircular holiday through a coating, deliberately introduced in order to expose the underlying metal substrate prior to expos
38、ure in a corrosive environment3.4corroded areaarea around a defect where the substrate has been attacked by corrosion3.5delaminated areaarea around a defect where loss of adhesion of a coating from a substrate or an underlying coating has occurred3.6scribelinear holiday through a coating, deliberate
39、ly introduced in order to expose the underlying metal substrate prior to exposure in a corrosive environment4 PrincipleThe delamination around a scribe or other artificial defect is assessed either directly at the end of the test period, immediately after removal of the test panel from a previous co
40、nditioning environment, or after conditioning for a specified period.The corrosion around the scribe or other artificial defect is assessed either immediately after removal of the test panel from a previous conditioning environment or after removal of the coating.Both the degree of delamination and
41、the degree of corrosion are determined by measurement and calculation.5 Procedure5.1 GeneralThe assessment of delamination shall be made immediately after removal of the panels from the conditioning environment (5.2.1) unless otherwise specified or agreed, in which case assessment may be made after
42、a further conditioning period, during which adhesion might recover (5.2.2).The assessment of corrosion may be made on the coated panel (5.3.1) or, if agreed or otherwise specified, after stripping off the coating (5.3.2).If corrosion is to be assessed after stripping off the coating, this is carried
43、 out after any assessment of delamination.Testing of at least three individual test panels is required unless otherwise specified or agreed.5.2 Assessment of delamination5.2.1 Directly at the end of the test periodRinse the test panel with fresh tap water immediately after exposure, i.e. before the
44、coating dries out, blow off residues of water from the surface using compressed air if necessary, and inspect for visible changes. Carefully remove loose coating using a knife blade held at an angle, positioning the blade at the coating/substrate interface and forcing the coating away from the subst
45、rate.Depending upon the coating type and degree of delamination, some force might be necessary to remove the coating, but a boundary should be found where the coating becomes tightly adhered to the substrate, this being the limit of delamination. To be able to correctly determine where this boundary
46、 between weak and tight adhesion lies, it is necessary to assess the adhesion beyond the boundary.2 ISO 2012 All rights reservedBS EN ISO 4628-8:2012ISO 4628-8:2012(E)If the adhesion of the coating to the substrate has deteriorated to the extent that no boundary can be found and the coating can be e
47、asily removed up to the edge of the test panel, this should be noted in the test report.If desired, compressed air or an adhesive tape may be used instead of a knife blade. It is important to remove the loose coating completely.If necessary, rinse the test panel again with fresh tap water.Measure wi
48、th a ruler, to the nearest 0,5 mm, the total width of delamination at a minimum of six points uniformly distributed along the scribe or around the artificial defect (see Figure 1, measurements a to f). Ignore delamination beyond the beginning and end of the original scribe.If more accurate measureme
49、nt is required, a magnifier with suitable scale may be used.Delamination may be measured over more than six points if the test standard being followed requires, provided this information is included in the test report. Similarly, for a scribed line of length less than 50 mm, fewer than six measurements may be made, provided that each measurement is a minimum of 6 mm apart and information is included in the test report.a) Scribe b) Circular defectKey1 corroded or delaminated area2 width of origina
