1、BRITISH STANDARD BS EN ISO 6988:1995 Incorporating Amendment No. 1 Metallic and other non-organic coatings Sulfur dioxide test with general condensation of moisture The European Standard EN ISO 6988:1994 has the status of a British StandardBSENISO6988:1995 This British Standard, having been prepared
2、 under the directionof the Surface Coatings(other than Paints) Standards Committee, was published under the authority ofthe Board of BSI and comes intoeffect on 31January1986 BSI 02-2000 The following BSI references relate to the work on this standard: Committee reference SRC/15 Draft for comment 82
3、/53055 DC ISBN 0 580 14915 3 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Surface Coatings (other than Paints) Standards Committee (SRC/-) to Technical Committee SRC/15, upon which the following bodies were represented: Aluminium Fede
4、ration Association of Manufacturers of Domestic Electrical Appliances British Anodising Association British Industrial Fasteners Federation Electronic Engineering Association Institute of Metal Finishing Metal Finishing Association Ministry of Defence NDT Trade Association Society of Motor Manufactu
5、rers and Traders Limited Telecommunication Engineering and Manufacturing Association (TEMA) Zinc Development Association Amendments issued since publication Amd. No. Date of issue Comments 8507 April 1995 Indicated by a sideline in the marginBSENISO6988:1995 BSI 02-2000 i Contents Page Committees re
6、sponsible Inside front cover National foreword ii Foreword 2 0 Introduction 3 1 Scope and field of application 3 2 References 3 3 Apparatus and material 3 4 Test specimens 4 5 Method of exposure of test specimens 4 6 Procedure 4 7 Test duration 5 8 Cleaning of specimens after test 5 9 Evaluation of
7、results 5 10 Test report 5 Annex ZA (normative) Normative references to international publications with their relevant European publications 7 National appendix A Corrected figures 8 Figure 1 Cabinet with door 6 Figure 2 Hooded apparatus 6 Publications referred to Inside back coverBSENISO6988:1995 i
8、i BSI 02-2000 National foreword This Part of BS 5466 has been prepared under the direction of the Surface Coatings (other than Paints) Standards Committee. It is identical with ISO6988:1985 “Metallic and other non-organic coatings Sulfur dioxide test with general condensation of moisture”, which has
9、 been prepared, with the active participation of the UnitedKingdom, by Subcommittee7, Corrosion tests, of Technical Committee107, Metallic and other non-organic coatings, of the International Organization for Standardization (ISO). It is intended to publish further Parts as the international work pr
10、ogresses. In 1994 the European Committee for Standardization (CEN) accepted ISO6988:1985 as European Standard EN ISO6988:1994. As a consequence of implementing the European Standard this British Standard is renumbered as BSEN ISO6988 and any reference to BS5466-8 should be read as a reference to BS
11、EN ISO6988. Terminology and conventions. The text of the International Standard has been approved as suitable for publication as a British Standard without deviation. Some terminology and certain conventions are not identical with those used in British Standards; attention is drawn especially to the
12、 following. The comma has been used as a decimal marker. In British Standards it is current practice to use a full point on the baseline as the decimal marker. Where the words “International Standard” appear, referring to this standard, they should be read as “Part of BS5466”. In British Standards i
13、t is current practice to use the spelling “sulphur” etc., instead of “sulfur”, etc. The Technical Committee has reviewed the provisions of ISO1462:1973, to which reference is made in clause 9, and has decided that it is acceptable for use in conjunction with this standard. The British Standard relat
14、ed to ISO1462 is BS3745:1970 “The evaluation of results of accelerated corrosion tests on metallic coatings”. When used as described in clause9, BS3745 will give the same results as ISO1462 and is therefore suitable for use in this connection. Textual errors. When adopting the text of the Internatio
15、nal Standard, the textual errors given below were discovered. They have been marked in the text and have been reported to ISO in a proposal to amend the text of the International Standard. InFigure 1 andFigure 2 an incorrect graphical symbol has been used to represent water. In order to aid users of
16、 this Part of BS5466, corrected versions of these figures are reproduced inNational appendix A. Cross-references International Standard Corresponding British Standard ISO 4540:1980 BS 5466 Methods for corrosion testing of metallic coatings Part 6:1982 Rating of results of corrosion testing on electr
17、oplated coatings cathodic to the substrate (Identical)BSENISO6988:1995 BSI 02-2000 iii A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of i
18、tself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi toiv, theENISO title page, pages2 to8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporat
19、ed. This will be indicated in the amendment table on the inside front cover.iv blankEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6988 October 1994 ICS 25.220.30; 25.220.40 Descriptors: Coatings, metal coatings, non organic coatings, tests, corrosion tests, test equipment, sulphur dioxide
20、 English version Metallic and other non organic coatings Sulfur dioxide test with general condensation of moisture (ISO6988:1985) Revtements mtalliques et autres revtements non organiques Essai au dioxyde de soufre avec condensation gnrale de lhumidit (ISO6988:1985) Metallische und andere anorganisc
21、he berzge Prfung mit Schwefeldioxid unter allgemeiner Feuchtigkeitskondensation (ISO6988:1985) This European Standard was approved by CEN on1994-10-26. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the statu
22、s 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 Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French, German). A ve
23、rsion in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Denmark, Finland, France, Germany, G
24、reece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1994 Copyright re
25、served to CEN members Ref. No. EN ISO6988:1994 EENISO6988:1994 BSI 02-2000 2 Foreword This European Standard was taken over by the Technical Committee CEN/TC262, Protection of metallic materials against corrosion, from the work of ISO/TC107, Metallic and other inorganic coatings, of the Internationa
26、l Organization for Standardization (ISO). CEN/TC262 has decided to submit the final draft for formal vote. The result was positive. 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 April1995, and c
27、onflicting national standards shall be withdrawn at the latest by April1995. According to the CEN/CENELEC Internal Regulations, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Net
28、herlands, Norway, Portugal, Spain, Sweden, Switzerland, UnitedKingdom. NOTENormative references to international publications are listed inAnnex ZA (normative).ENISO6988:1994 BSI 02-2000 3 0 Introduction 0.1 Moist air containing sulfur dioxide quickly produces easily visible corrosion of many metals
29、 in a form resembling that occurring in industrial environments. It is therefore a test medium well suited to detect pores or other sources of weakness in protective coatings and deficiencies in corrosion resistance associated with unsuitable alloy composition or treatments. The results obtained in
30、the test should not be regarded as a direct guide to the corrosion resistance of the tested materials in all environments where these materials may be used. Similarly, performances of different materials in the test should not be taken as a direct guide to the relative corrosion resistance of these
31、materials in service. 0.2 The exposure conditions may be varied by either proceeding continuously or in cycles of alternate exposure to the sulfur dioxide-containing atmosphere and to the ambient atmosphere. 0.3 The variant of the test to be used, the test duration, the type of test specimen and the
32、 criteria of failure are not specified in this International Standard. Such details are provided in appropriate material and product specifications. 1 Scope and field of application This International Standard specifies a method for assessing the resistance of materials or products to condensed mois
33、ture containing sulfur dioxide. The method has been found to be suitable for testing metallic and non-organic coatings. NOTEFor testing paints and varnishes, see ISO3231, Paints and varnishes Determination of resistance to humid atmospheres containing sulphur dioxide. 2 References ISO 1462, Metallic
34、 coatings Coatings other than those anodic to the basis metal Accelerated corrosion tests Method for the evaluation of the results. ISO 4540, Metallic coatings Coatings cathodic to the substrate Rating of electroplated test specimens subjected to corrosion tests. 3 Apparatus and material 3.1 Test ca
35、binet, of preferred capacity300 10dm 3 , with a door capable of being closed hermetically, and fitted with the components specified in3.2, 3.3 and3.4. Typical test cabinets are shown inFigure 1 andFigure 2. NOTETest cabinets of capacities other than300 10dm 3may be used, provided that the other test
36、 conditions to which the test specimens are submitted are the same. The details and instructions given in this International Standard are, however, appropriate to test cabinets of the preferred capacity and will require corresponding modifications for other capacities. 3.1.1 Materials of constructio
37、n All the materials used in the construction of the test cabinet shall be resistant to the action of moist sulfur dioxide and shall themselves not emit any gas or vapour likely to influence corrosion of the test specimens. The floor and lower parts of the walls shall be capable of being heated and s
38、hall be able to retain without leakage at least2,5dm 3of water containing dissolved sulfur dioxide, this volume being required to flush the apparatus. Lead-clad construction material is suitable for these parts and for the framework and fittings of the cabinet, but the greater part of the walls and
39、door should be made of transparent sheet, such as glass or suitable plastics material. A new cabinet shall be operated at least once, without introduction of test specimens, following the procedure applicable to an atmosphere containing2dm 3of sulfur dioxide, before it is brought into use for testin
40、g. This should reduce risks of contamination of the atmosphere by vapours from the materials of construction. 3.1.2 Shape Some variation in the shape of the test cabinet can be tolerated, but the roof should be shaped so that moisture condensing on it does not fall on test specimens in the test cabi
41、net. An inclination of the roof of about12 to the horizontal provides a suitable safeguard. 3.1.3 Ambient conditions The test cabinet shall be installed in a room in which there is a clean atmosphere and shall be protected from large or rapid temperature fluctuations, strong direct sunlight and drau
42、ghts. (See also6.5.2.) 3.2 Temperature-regulating device, with its actuating element placed in the upper part of the test cabinet, and a thermometer capable of being read from outside the cabinet with its bulb150mm from the roof and door and250mm from a side. 3.3 Gas inlet tube, through which gas ca
43、n be introduced into the test cabinet, placed about50mm above the base, a valve, by which excess pressure can be relieved, placed in or near the roof of the cabinet, and a drain-cock in the floor of the test cabinet.ENISO6988:1994 4 BSI 02-2000 3.4 Heating device, capable of heating the test cabinet
44、 to40 3 C in1,5h and of maintaining the interior at this temperature. (See6.5.) A1 kW electrically heated hotplate is suitable for the preferred size of test cabinet. 3.5 Source of sulfur dioxide, and means of measuring the volumes of gas required for delivery into the test cabinet. A container of l
45、iquid sulfur dioxide is the usual source, but the gas may be generated externally in suitable apparatus from sodium sulfite and sulfuric acid. The volume of gas delivered into the test cabinet may be measured by any suitable method, for example: a) by means of a gas burette using viscous liquid para
46、ffin as the pressure-controlling fluid. As the volume to be measured will usually be0,2dm 3 , measures shall be taken to avoid errors from causes such as air contained in delivery tubes between the burette and the chamber; b) by means of a gas jar of known volume filled with sulfur dioxide and opene
47、d in the chamber; c) by means of a calibrated flowmeter. 4 Test specimens 4.1 The number, type, shape and dimensions of test specimens, shall be selected according to the specification for the coating or product being tested. When not so specified, details concerning the specimens shall be agreed be
48、tween the interested parties. (See5.3.) 4.2 Thoroughly clean the test specimens before testing. The cleaning method employed will depend on the nature of the surface and the contaminants, but shall not include the use of any abrasives or solvents which may attack the surface of the test specimens. T
49、ake care that the test specimens are not recontaminated, after cleaning, by excessive or careless handling. 4.3 If test specimens are cut from a larger coated article, the cutting shall be carried out in such a way that the coating is not damaged, especially in the area adjacent to the cut. Unless otherwise specified, the cut edges shall be adequately protected by coating them with a suitable medium, stable under the conditions of the test, such as wax or adhesive tape. 5 Method of exposure of test specimens 5.1 Place the test speci
