ISO INTERNATIONAL STANDARD 12687 First edition 1996-12-15 Metallic coatings Porosity tests - Humid sulfur (flowers of sulfur) test Revetements métalliques - Essais de porosite - Essai a la fleur de soufreparvoiehumide ISo Reference number ISO12687:1996(E) Copyright Intermational Organization for Standardization rovided by IHS censewithIs rmitted without license from IHS Not for Resale ISO 12687:1996(E) Foreword isO (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 committees. Each member body interested in a subject for represented on that committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. IsO collaborates closely with the international Electrotechnical Commission (lEC)onall mattersofelectrotechnicalstandardization Draft International 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. ISO/TC 107. Metallic and other inorganic coatings, Subcommittee SC 7. Corrosion tests. @ISO1996 reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. InternationalOrganizationforStandardization Case Postale 56 . CH-1211 Geneve 20 · Switzerland Printed in Switzerland ed without license from IHS Not for Resale INTERNATIONALSTANDARD ISO ISO 12687:1996(E) Metallic coatings Porosity tests -- Humid sulfur (flowers of sulfur) test 1 Scope This International Standard specifies a method of revealing discontinuities and porosity in metallic coatings, where they penetrate the coating layer or layers down to a silver, copper or copper-alloy substrate. This method is especially useful for coatings consisting of single or combined layers of any coating that does not significantly tarnish in a reduced-sulfur atmosphere, such as gold, nickel, tin, tin-lead palladium and their alloys. This test method is designed to show whether or not the coating meets the requirement concerning an acceptable porosity level specified by the user. The value specified is usually determined by user's experience to be acceptable for the intended application. Recent reviews of porosity testing and test methods can be found in the literature [1], [2]. An IsO general guide to porosity tests for metallic and other inorganic coatings is available as IsO 10308:1995, Metallic coatings - Review ofporositytests. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the registers of currently valid International Standards. IsO2079:1981,Surface treatment andmetalliccoatings-Generalclassification of terms. Iso2080:1981, Electroplating and related processes-Vocabulary. 3 Definitions For the purposes of this International Standard, the following definitions apply (other relevant definitions can be found in ISO 2079 and ISO 2080). 3.1 corrosion products: Chemical products, derived from the substrate that usually protrude from the surface at discontinuities. The chemical reaction products form during the test and can be readily examined after the test exposure. They cannot be readily removed by mild air dusting [see clause 10, item b) 2]. 1 Copyright Intermational Organization for Standardization Not for Resale