1、BSI Standards PublicationBS ISO 21207:2015Corrosion tests in artificialatmospheres Acceleratedcorrosion tests involvingalternate exposure tocorrosion-promoting gases,neutral salt-spray and dryingBS ISO 21207:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO
2、21207:2015.It supersedes BS ISO 21207:2004 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/NFE/8, Corrosion of metals and alloys.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does n
3、ot purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 87571 7ICS 77.060Compliance with a British Standard cannot confer immunity fromlegal obligat
4、ions.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 December 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dBS ISO 21207:2015 ISO 2015Corrosion tests in artificial atmospheres Accelerated corrosion tests inv
5、olving alternate exposure to corrosion-promoting gases, neutral salt-spray and dryingEssais de corrosion en atmosphres artificielles Essais de corrosion acclre par expositions alternes des gaz oxydants ou au brouillard salin neutre et un schageINTERNATIONAL STANDARDISO21207Second edition2015-12-15Re
6、ference numberISO 21207:2015(E)BS ISO 21207:2015ISO 21207:2015(E)ii ISO 2015 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2015, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any me
7、ans, electronic or mechanical, including photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-12
8、14 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 21207:2015ISO 21207:2015(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Apparatus and reagents 14 Evaluation of the corrosivity of the tests . 24.1 Reference test panels . 24.2
9、Arrangement of the reference panels during testing . 34.3 Determination of mass loss after testing 34.4 Satisfactory performance of test 35 Test objects . 46 Procedure. 46.1 Test method A 46.1.1 Test cycle . 46.1.2 Salt spray testing followed by drying (step a) 46.1.3 Exposure to corrosive gases fol
10、lowed by drying (step b) . 56.1.4 Test duration . 56.2 Test method B 56.2.1 Test cycle . 56.2.2 Salt spray testing followed by drying (step a or step c) . 66.2.3 Exposure to corrosive gases (step b or step d) 66.2.4 Test duration . 67 Evaluation of results . 68 Test report . 7Annex A (informative) R
11、ecommended test periods 8Bibliography 9 ISO 2015 All rights reserved iiiContents PageBS ISO 21207:2015ISO 21207:2015(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Stan
12、dards is normally carried out through ISO technical 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 t
13、ake part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.The procedures used to develop this document and those intended for its further maintenance are described in the ISO/IEC Directives, Part 1. In p
14、articular the different approval criteria needed for the different types of ISO documents should be noted. This document was drafted in accordance with the editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives). Attention is drawn to the possibility that some of the elements
15、of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the document will be in the Introduction and/or on the ISO list of patent declarations received (se
16、e www.iso.org/patents). Any trade name used in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence
17、to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Foreword - Supplementary informationThe committee responsible for this document is ISO/TC 156, Corrosion of metals and alloys.This second edition cancels and replaces the first edition (ISO 21207:2004), of which it
18、 constitutes a minor revision. It also incorporates the Technical Corrigendum ISO 21207:2004/Cor 1:2008.iv ISO 2015 All rights reservedBS ISO 21207:2015ISO 21207:2015(E)IntroductionCorrosion of metallic materials with or without corrosion protection is influenced by many environmental factors, the i
19、mportance of which can vary with the type of metallic material and with the type of environment. Laboratory tests are designed to simulate the effects of the most important factors that enhance the corrosion of metallic materials.The accelerated corrosion test methods described in this International
20、 Standard, methods A and B, are designed to simulate and enhance the environmental influence of exposure to an outdoor climate where salt-contaminated conditions and corrosion-promoting gases from an industrial or a traffic environment occur which might promote corrosion. Test method A simulates a m
21、oderately aggressive traffic environment while test method B simulates a more severe industrial or traffic environment.Test method A involves exposure of the test objects to the following test cycle:a) neutral salt spray testing (ISO 9227) for 2 h in a mist of a sodium chloride salt solution of mass
22、 fraction 5 % at 35 C, followed by drying for 22 h in a standard laboratory climate;b) exposure for 120 h in a test atmosphere containing a mixture of corrosion-promoting gases, volume fraction of NO2equal to 1,5 106and of SO2equal to 0,5 106, at a relative humidity of 95 % and at a temperature of 2
23、5 C, followed by drying for 24 h in a standard laboratory climate.Test method B involves exposure of the test objects to the following test cycle:a) neutral salt spray testing (ISO 9227) for 2 h in a mist of a sodium chloride salt solution of mass fraction 5 % at 35 C, followed by drying for 22 h in
24、 a standard laboratory climate;b) exposure for 48 h in a test atmosphere containing a mixture of corrosion-promoting gases, volume fraction of NO2equal to 10 106and of SO2equal to 5 106, at a relative humidity of 95 % and at a temperature of 25 C;c) neutral salt spray testing (ISO 9227) for 2 h in a
25、 mist of a sodium chloride salt solution of mass fraction 5 % at 35 C, followed by drying for 22 h in a standard laboratory climate;d) exposure for 72 h in a test atmosphere containing a mixture of corrosion-promoting gases, volume fraction of NO2equal to 10 106and of SO2equal to 5 106, at a relativ
26、e humidity of 95 % and at a temperature of 25 C.The results obtained do not permit far-reaching conclusions on the corrosion resistance of the tested product under the whole range of environmental conditions in which it may be used. ISO 2015 All rights reserved vBS ISO 21207:2015BS ISO 21207:2015Cor
27、rosion tests in artificial atmospheres Accelerated corrosion tests involving alternate exposure to corrosion-promoting gases, neutral salt-spray and drying1 ScopeThis International Standard defines two accelerated corrosion test methods to be used in assessing the corrosion resistance of products wi
28、th metals in environments where there is a significant influence of chloride ions, mainly as sodium chloride from a marine source or by winter road de-icing salt, and of corrosion-promoting gases from industrial or traffic air pollution.This International Standard specifies both the test apparatus a
29、nd test procedures to be used in executing the accelerated corrosion tests.The methods are especially suitable for assessing the corrosion resistance of sensitive products with metals, e.g. electronic components, used in traffic and industrial environments.2 Normative referencesThe following documen
30、ts, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 8407, Corrosion of metals
31、 and alloys Removal of corrosion products from corrosion test specimensISO 9227, Corrosion tests in artificial atmospheres Salt spray testsISO 10062, Corrosion tests in artificial atmosphere at very low concentrations of polluting gas(es)ISO 10289, Methods for corrosion testing of metallic and other
32、 inorganic coatings on metallic substrates Rating of test specimens and manufactured articles subjected to corrosion tests3 Apparatus and reagents3.1 Exposure of test objects to mixtures of NO2and SO2at a relative humidity of 95 % and a temperature of 25 C.The climatic cabinet with inner chamber and
33、 gas flow system shall comply with the requirements of ISO 10062.The equipment used for testing shall be constructed for the following reasons.a) The inner chamber and gas flow system consist of inert materials, e.g. PTFE (polytetrafluoroethylene) or glass, to avoid or minimize adsorption of hostile
34、 gases on surfaces other than of that of the test panels.b) Airflow and hostile gas injection system are designed to ensure uniform test conditions in the inner chamber or working space of cabinet.In the most common design of test equipment, the test atmosphere in the working space is obtained by co
35、ntinuously introducing the necessary quantity of the mixture of corrosion-promoting gases into a damp airflow to obtain the required concentration. The corrosion-promoting gases and conditioned air are mixed outside the cabinet. The conditioned air is taken from the outer chamber of the climatic cab
36、inet. The airflow after injection of the corrosion-promoting gases is then mixed INTERNATIONAL STANDARD ISO 21207:2015(E) ISO 2015 All rights reserved 1BS ISO 21207:2015ISO 21207:2015(E)with a flow of re-circulated test atmosphere and the resulting gas flow admitted into the inner chamber or working
37、 space of the cabinet. Half of the flow of the test atmosphere through the inner chamber may be re-circulated.To ensure uniform test conditions in the working space, the test atmosphere is normally supplied to the working space from the bottom and the outlet is placed at the top. Perforated plates a
38、re placed in front of the openings to ensure uniform airflow through the working space.c) Uniformity of temperature in the working space shall be better than 1 C and uniformity of relative humidity better than 3 %. In terms of corrosivity, expressed as the corrosion rate of copper metal, the uniform
39、ity shall be not less than 5 %.NOTE The uniformity of the test conditions in the working space may be checked regularly by exposing a number of copper metal coupons, placed at different positions in the working space during testing. The differences in weight change of the metal coupons indicate if t
40、he uniformity of test conditions is within the specified range.d) The tolerance of the damp air flow shall be within 1 C of the specified temperature and the tolerance on relative humidity 3 %. The linear flow rate of air shall be in the range of 0,5 mm/s to 5 mm/s. The damp airflow shall be free of
41、 water droplets or aerosols.In the most common design of test equipment, the air is introduced to the outer chamber of the cabinet after filtration and purification by activated charcoal and a particulate filter. The nitrogen dioxide and the sulfur dioxide gases may be taken either from pressurized
42、cylinders filled with a volume fraction of 0,001 % high-purity gases with a volume fraction of 1 000 106in high-purity nitrogen gas or from thermostat-controlled permeation tubes.e) For exposure of test panels in the working space, specimen holders shall be used so that the test panels do not shield
43、 one another or disturb the uniformity of airflow across the chamber.f) The temperature, relative humidity, and concentration of sulfur dioxide and nitrogen dioxide in the airflow at the outlet of working space shall be monitored so that they reflect the true test conditions for the test objects.3.2
44、 Salt spray testing in accordance with ISO 9227.The apparatus and reagents to be used shall comply with the requirements of ISO 9227.3.3 Drying in standard laboratory climate.For the test, a room with an appropriate system for control of its temperature at 23 C 2 C and its relative air humidity at 5
45、0 % 5 % shall be used.4 Evaluation of the corrosivity of the tests4.1 Reference test panelsFor measurement of the corrosivity of the tests in accordance with this International Standard, four reference panels of metallic copper (minimum 99,85 % mass fraction of Cu) shall be used.The reference specim
46、ens shall have dimensions of 50 mm 50 mm 1 mm.Prior to exposure, grinding and polishing of the surfaces of the reference panels including edges shall be made by metallographic sample preparation equipment as follows:a) test panel shall be mounted on a flat specimen holder using double-sided tape;b)
47、front surface of panel shall be ground on paper (220 grit) with a water lubricant until flat;2 ISO 2015 All rights reservedBS ISO 21207:2015ISO 21207:2015(E)c) front surface of panel and edges of panel shall be polished for 5 min on cloth with 15 m diamond suspension and an ethanol lubricant;d) pane
48、l shall be removed from the holder and steps a) to c) repeated but with the back side uppermost;e) identification number shall be stamped on the panel;f) panel shall be polished using 9 m diamond suspension and tissue paper manually;g) panel shall be cleaned with ethanol and wiped with tissue paper
49、manually;h) panel shall be cleaned in an ultrasonic bath with ethanol and then blown dry;i) panel shall be stored in a desiccator for a minimum period of 30 min;j) panel shall be weighed to the nearest 0,1 mg.4.2 Arrangement of the reference panels during testingDuring testing, the reference panels shall be handled in the same way as the test objects. During salt spray testing and exposure testing in the flow of the mixed corrosive gases, the four reference panels shall be positioned in the four
