1、Determination of resistance to intergranular corrosion of stainless steelsPart 3: Corrosion test for low-Cr ferritic stainless steelsBS ISO 3651-3:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017Determination of resistance to intergranular corrosion of s
2、tainless steels Part 3: Corrosion test for low-Cr ferritic stainless steelsDtermination de la rsistance la corrosion intergranulaire des aciers inoxydables Partie 3: Essai de corrosion pour les aciers inoxydables ferritiques faible teneur en chromeINTERNATIONAL STANDARDISO3651-3First edition2017-05R
3、eference numberISO 3651-3:2017(E)National forewordThis British Standard is the UK implementation of ISO 3651-3:2017.The UK participation in its preparation was entrusted to Technical Committee ISE/NFE/8, Corrosion of metals and alloys.A list of organizations represented on this committee can be obta
4、ined on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 80708 4ICS 77.060Compliance with a
5、 British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 36513:2017 ISO 2017Determinat
6、ion of resistance to intergranular corrosion of stainless steels Part 3: Corrosion test for low-Cr ferritic stainless steelsDtermination de la rsistance la corrosion intergranulaire des aciers inoxydables Partie 3: Essai de corrosion pour les aciers inoxydables ferritiques faible teneur en chromeINT
7、ERNATIONAL STANDARDISO3651-3First edition2017-05Reference numberISO 3651-3:2017(E)BS ISO 36513:2017ISO 3651-3:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be repro
8、duced or utilized otherwise in any form or by any means, 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
9、.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 36513:2017ISO 3651-3:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved.
10、 Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, 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
11、the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgISO 3651-3:2017(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13
12、Terms and definitions . 14 Preparation of test specimens 14.1 Principle 14.2 Dimensions . 24.3 Welded test pieces . 44.4 Sensitization heat treatment . 44.5 Mechanical preparation 44.6 Degreasing and drying . 45 Test methods . 46 Evaluation by metallographic examination 67 Test report . 6Bibliograph
13、y 7 ISO 2017 All rights reserved iiiContents PageBS ISO 36513:2017ISO 3651-3:2017(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 throu
14、gh 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 take part in the work. ISO collabora
15、tes 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 particular the different approval c
16、riteria 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 of this document may be the subj
17、ect 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 (see www .iso .org/ patents).Any tr
18、ade name used in this document is information given for the convenience of users and does not constitute an endorsement. For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adhe
19、rence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys.A list of all parts in the ISO 3651 series can be fou
20、nd on the ISO website.iv ISO 2017 All rights reservedBS ISO 36513:2017ISO 3651-3:2017(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 t
21、hrough 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 take part in the work. ISO colla
22、borates 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 particular the different approv
23、al 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 of this document may be the
24、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 (see www .iso .org/ patents).An
25、y 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 voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs
26、adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 156, Corrosion of metals and alloys.A list of all parts in the ISO 3651 series can be
27、 found on the ISO website.iv ISO 2017 All rights reserved ISO 3651-3:2017(E)IntroductionThe term “intergranular corrosion test” denotes the corrosion test carried out by means of preferential attack of the grain boundaries.The low-Cr less than 16 % Cr, less than 0,3 % Ni, less than 0,3 % Ti and less
28、 than 0,3 % Nb, less than 0,3 % (Ti + Atomic weight ratio Nb) ferritic stainless steels may be subject to such attack when they have been exposed to a temperature between about 500 C to 1 300 C. This heat cycle, which may provoke sensitization to intergranular corrosion, may occur during rolling or
29、welding operation.Low-Cr ferritic stainless steels may show high risks to uniform corrosion rates and copper deposit when tested by the methods given by ISO 3651-1 and ISO 3651-2 since the electrochemical potential difference between the matrix and the Cr depletion for low-Cr ferritic stainless stee
30、ls is much less than that of medium-Cr ferritic stainless steels. These risks should be considered in selecting this test method. Application of this standard test to the other stainless steels out of the above specifications should be made based on the specific agreement between the interested part
31、ies. ISO 2017 All rights reserved vBS ISO 36513:2017BS ISO 36513:2017Determination of resistance to intergranular corrosion of stainless steels Part 3: Corrosion test for low-Cr ferritic stainless steels1 ScopeThis document specifies the determination of the intergranular corrosion susceptibility of
32、 low-Cr less than 16 % Cr, less than 0,3 % Ni, less than 0,3 % Ti and less than 0,3 % Nb, less than 0,3 % (Ti + Atomic weight ratio Nb) ferritic stainless steels in the 0,5 % sulfuric acid/copper sulfate test. It also specifies the purposes which may be assigned to the test.The method is applicable
33、to stainless steels supplied in the form of rolled sheets and welded tubes and intended for use in a mildly oxidizing acid medium.It is important to note that the result of the corrosion test is only strictly valid for the corrosive medium used in the test. It constitutes a basis for estimating the
34、resistance to intergranular corrosion but cannot be used to check resistance to other forms of corrosion (general corrosion, pitting, stress corrosion, etc.). It is important for the user to adapt the specified corrosion test where steels are used. This test is, in no case, considered as an absolute
35、 criterion of the quality of the metal.2 Normative referencesThe following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition
36、 of the referenced document (including any amendments) applies.ISO 8044, Corrosion of metals and alloys Basic terms and definitions3 Terms and definitionsFor the purposes of this document, the terms and definitions given in ISO 8044 apply.ISO and IEC maintain terminological databases for use in stan
37、dardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp4 Preparation of test specimens4.1 PrincipleDepending on the purpose of the test and agreement between supplier and purcha
38、ser, the test pieces shall be prepared as specified in 4.2, 4.3 or 4.4. The thickness of the test specimen can be the same as the original samples.INTERNATIONAL STANDARD ISO 3651-3:2017(E) ISO 2017 All rights reserved 1BS ISO 36513:2017ISO 3651-3:2017(E)4.2 DimensionsA specimen having a total surfac
39、e area of 5 cm2to 20 cm2is recommended. It should include welded zone, heat-affected zone and unaffected base metal.Dimensions in millimetresKey1 no sampling area (avoid weld defects)2 sampling area3 welding sample4 no sampling areaFigure 1 Test piece for plates and strips with welded butt joint2 IS
40、O 2017 All rights reservedBS ISO 36513:2017ISO 3651-3:2017(E)4.2 DimensionsA specimen having a total surface area of 5 cm2to 20 cm2is recommended. It should include welded zone, heat-affected zone and unaffected base metal.Dimensions in millimetresKey1 no sampling area (avoid weld defects)2 sampling
41、 area3 welding sample4 no sampling areaFigure 1 Test piece for plates and strips with welded butt joint2 ISO 2017 All rights reserved ISO 3651-3:2017(E)Key1 welding sample2 welding sample3 sampling areaFigure 2 Test piece for plates and strips with crossing welded butt jointKey1 sampling area2 weldi
42、ng samplesFigure 3 Longitudinal test piece for tubes with welded butt joint ISO 2017 All rights reserved 3BS ISO 36513:2017ISO 3651-3:2017(E)Key1 sampling area2 welding samplesFigure 4 Circumferential test piece for tubes with welded butt joint4.3 Welded test piecesWelded test pieces are prepared ac
43、cording to Figures 1 to 4.As-received heat treatment shall be specified.4.4 Sensitization heat treatmentIn order to verify the intrinsic resistance to intergranular corrosion, it is necessary to carry out a sensitization heat treatment for low-Cr ferritic stainless steel as follows:Step1: heating th
44、e specimen at 1 200 C 10 C for 30 min followed by water cooling;Step2: heating the specimen at 600 C 10 C for 30 min followed by water cooling.4.5 Mechanical preparationThe test pieces shall be descaled mechanically by grinding in the longitudinal plane on all surfaces and sharp edges with grade 600
45、 or finer, iron-free abrasive paper or cloth.Over-heating of the test pieces shall be avoided.4.6 Degreasing and dryingThe test piece shall be degreased using a suitable degreasing agent such as acetone or ethanol and dried before being placed into the corrosion solution.5 Test methods5.1 Apparatus5
46、.1.1 A flask, with a capacity of 1 l with a condenser.4 ISO 2017 All rights reservedBS ISO 36513:2017ISO 3651-3:2017(E)Key1 sampling area2 welding samplesFigure 4 Circumferential test piece for tubes with welded butt joint4.3 Welded test piecesWelded test pieces are prepared according to Figures 1 t
47、o 4.As-received heat treatment shall be specified.4.4 Sensitization heat treatmentIn order to verify the intrinsic resistance to intergranular corrosion, it is necessary to carry out a sensitization heat treatment for low-Cr ferritic stainless steel as follows:Step1: heating the specimen at 1 200 C
48、10 C for 30 min followed by water cooling;Step2: heating the specimen at 600 C 10 C for 30 min followed by water cooling.4.5 Mechanical preparationThe test pieces shall be descaled mechanically by grinding in the longitudinal plane on all surfaces and sharp edges with grade 600 or finer, iron-free a
49、brasive paper or cloth.Over-heating of the test pieces shall be avoided.4.6 Degreasing and dryingThe test piece shall be degreased using a suitable degreasing agent such as acetone or ethanol and dried before being placed into the corrosion solution.5 Test methods5.1 Apparatus5.1.1 A flask, with a capacity of 1 l with a condenser.4 ISO 2017 All rights reserved ISO 3651-3:2017(E)5.1.2 Heating device, to keep the solution boiling.5.1.3 Metallographic microscope, magni
