1、BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06Anodizing of aluminium and its alloys - Assessment of quality of sealed anodic oxidation coatings by measurement of admittanceBS EN ISO 2931:2018National forewordThis British Standard is the UK implementation of EN ISO
2、2931:2018. It is identical to ISO 2931:2017. It supersedes BS EN ISO 2931:2010, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee STI/33, Electrodeposited and related coatings.A list of organizations represented on this committee can be obtained on reque
3、st 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 2018 Published by BSI Standards Limited 2018ISBN 978 0 580 92454 5ICS 25.220.20Compliance with a British S
4、tandard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 February 2018.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN ISO 2931:2018EUROPEAN STANDARDNORME E
5、UROPENNEEUROPISCHE NORMEN ISO 2931February 2018ICS 25.220.20 Supersedes EN ISO 2931:2010EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2018 CEN Ref. No. EN ISO 2931:2018: EAll rights o
6、f exploitation in any form and by any means reserved worldwide for CEN national MembersAnodizing of aluminium and its alloys - Assessment of quality of sealed anodic oxidation coatings by measurement of admittance (ISO 2931:2017)Anodisation de laluminium et de ses alliages - valuation de la qualit d
7、es couches anodiques colmates par mesurage de ladmittance (ISO 2931:2017)Anodisieren von Aluminium und Aluminiumlegierungen - Prfung der Qualitt von verdichteten, anodisch erzeugten Oxidschichten durch Messung des Scheinleitwertes (ISO 2931:2017)This European Standard was approved by CEN on 1 Decemb
8、er 2017.CEN members are bound to comply with the CEN/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 obtai
9、ned on application to the CEN-CENELEC Management Centre 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-
10、CENELEC Management Centre has the same status as the 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, I
11、taly, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.English VersionEN ISO 2931:2018 (E)European forewordThis document (EN ISO 2931:2018) has been prepared by Technical Committee
12、ISO/TC 79 “Light metals and their alloys“ in collaboration with Technical Committee CEN/TC 132 “Aluminium and aluminium alloys”, the secretariat of which is held by AFNOR.This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorse
13、ment, at the latest by August 2018, and conflicting national standards shall be withdrawn at the latest by August 2018.Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN shall not be held responsible for identifying any or all su
14、ch patent rights.This document supersedes EN ISO 2931:2010.According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
15、Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.Endorsement noticeThe
16、 text of ISO 2931:2017 has been approved by CEN as EN ISO 2931:2018 without any modification.2BS EN ISO 2931:2018ISO 2931:2017(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Principle 25 Apparatus and materials 26 Test specimen 36.1 Sampling . 36.2 Treatme
17、nt before testing 37 Procedure. 38 Expression of results 49 Test report . 4Bibliography 5 ISO 2017 All rights reserved iiiContents PageBS EN ISO 2931:2018ISO 2931:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO membe
18、r bodies). The work of preparing International Standards 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, governmenta
19、l and non-governmental, in liaison with ISO, also take 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 ar
20、e described in the ISO/IEC Directives, Part 1. In particular 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 d
21、rawn to the possibility that some of the elements 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 o
22、n the ISO list of patent declarations received (see 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 voluntary nature of standards, the meaning of ISO specific terms and expres
23、sions related to conformity assessment, as well as information about ISOs 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 79, Light metals
24、 and their alloys, Subcommittee SC 2, Organic and anodic oxidation coatings on aluminium.This fourth edition cancels and replaces the third edition (ISO 2931:2010), which has been technically revised.The main changes compared to the previous edition are as follows: the content of Clause 6, now entit
25、led “Test specimen”, has been revised.iv ISO 2017 All rights reservedBS EN ISO 2931:2018ISO 2931:2017(E)IntroductionThe test described in this document is intended to give a quick, non-destructive assessment of the quality of sealed anodic oxidation coatings and is very suitable for routine producti
26、on control. It is carried out following sealing and before any other supplementary process is undertaken, for example, oiling, waxing or lacquering.The correlation of the results obtained with those of other tests that can assess sealing quality such as that of ISO 2143 can be affected by the presen
27、ce of sealing additives or contaminants such as silicate or phosphate. For this reason, the quality is checked from time to time by one of the reference acid-dissolution methods specified in ISO 3210.The pre-treatment, the anodizing process, the colouring process used and the alloy can all have an e
28、ffect on admittance readings. ISO 2017 All rights reserved vBS EN ISO 2931:2018This page deliberately left blankAnodizing of aluminium and its alloys - Assessment of quality of sealed anodic oxidation coatings by measurement of admittance1 ScopeThis document specifies a method for assessing the qual
29、ity of sealed anodic oxidation coatings on aluminium and its alloys by measurement of the admittance.The method is applicable to anodic oxidation coatings sealed in an aqueous medium.NOTE 1 Results obtained from anodic oxidation coatings sealed by different methods, e.g. hydrothermal sealing and col
30、d sealing, are not necessarily comparable.NOTE 2 Results obtained from anodic oxidation coatings on alloys containing more than 2 % silicon or 5 % manganese or 3 % magnesium are not comparable with results obtained from anodic oxidation coatings on more dilute alloys.The method is suitable for use a
31、s a production-control test and as an acceptance test where there is agreement between the anodizer and the customer.Any type of anodized component can be tested by the method described, provided that there is a sufficient area (a circle of diameter about 20 mm) and that the film thickness is greate
32、r than 3 m.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 of the referenced document
33、(including any amendments) applies.ISO 2360, Non-conductive coatings on non-magnetic electrically conductive base metals Measurement of coating thickness Amplitude-sensitive eddy-current methodISO 7583, Anodizing of aluminium and its alloys Terms and definitions3 Terms and definitionsFor the purpose
34、s of this document, the terms and definitions given in ISO 7583 and the following apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses: IEC Electropedia: available at http:/www.electropedia.org/ ISO Online browsing platform: available at http:/www
35、.iso.org/obp3.1admittanceY inverse of the complex apparent resistance, ZYZ=1/Note 1 to entry: In an alternating current circuit, Z (impedance) is represented by the vectorial sum of actual resistance, R, and the reactance, Xc, using INTERNATIONAL STANDARD ISO 2931:2017(E) ISO 2017 All rights reserve
36、d 1BS EN ISO 2931:2018ISO 2931:2017(E)ZXR=+c2 2where R is the resistance, in ohms;XfCc=12piis the reactance;wheref is the frequency of the alternating current;C is the capacitance.4 PrincipleAn anodic oxidation coating on aluminium is represented as an electrical diagram made up of a number of ohmic
37、 and capacitive resistances mounted in series and/or parallel in an alternating-current circuit. The numerical value of these resistances depends upon a number of variables including the following:a) basis metal (for example, composition, size and distribution of intermetallic compounds, and surface
38、 condition);b) type of sealing process (for example, steam, hot water, nickel or cobalt salts or cold sealing) and the conditions used;c) thickness and density of the anodic oxidation layer (depending upon electrolyte, type of current, current density, electrolyte temperature, etc.);d) dyeing or pig
39、mentation processes used to colour the anodic oxidation coating;e) time and conditions of storage between sealing and measurement.Thus, the test method differs from those of ISO 3210 and ISO 2143, which are only sensitive to sealing at the surface of the anodic oxidation coating.5 Apparatus and mate
40、rials5.1 Device for measuring admittance, covering a range of at least 3 S to 200 S.The instrument shall measure at a frequency of 1 000 Hz 10 Hz and be equipped with two electrodes, one with a contact screw by means of which a connection shall be made with the basis metal of the test specimen, and
41、the other with a pencil-like probe.5.2 Cell, containing the electrolyte, formed conveniently by a rubber ring of internal diameter 13 mm and thickness approximately 5 mm, the surface of which is self-adhesive. This type of cell has an internal area of 133 mm2. The internal area of the cell shall be
42、between 100 mm2and 200 mm2.5.3 Electrolyte, aqueous solution of potassium sulfate, 35 g/l.2 ISO 2017 All rights reservedBS EN ISO 2931:2018ISO 2931:2017(E)6 Test specimen6.1 SamplingWherever practicable, test specimens shall be production components or cut from production components. The test shall
43、be carried out on a significant surface and shall not be near an edge because of possible non-uniformity. The area of the test specimen shall be sufficient to determine the thickness of the coating at the point of measurement, to apply the electrolyte-filled cell and, if necessary, to determine the
44、surface area tested.Where it is impossible to test the production component itself, a test specimen which is representative of the production component may be used. In this case, the test specimen used shall be made from the same material and prepared under the same conditions of finishing as those
45、used for the preparation of the product.The aluminium alloy, the manufacturing conditions (kind and temper of the material), and the surface condition before treatment shall be the same as those of the product.The pretreatment, anodizing, colouring, and sealing shall be performed in the same bath an
46、d under the same conditions as the treatment of the product. Where the substrate of the test specimen is composed of extruded aluminium or rolled aluminium, the orientation of the extruded or rolling direction to the bending direction (i.e. orthogonal or parallel to the bending direction) shall be r
47、eported in the test report.6.2 Treatment before testingThe test area shall be clean, free from dirt, stains and other foreign matters. Any deposits or stains shall be removed with a clean, soft cloth or similar material which is wetted by water or an appropriate organic solvent such as ethanol. Orga
48、nic solvents which can corrode the test specimen or generate protective films on the test specimen shall not be used.7 ProcedureCarry out the test preferably within 1 h to 4 h after sealing and cooling to room temperature, and, in any case, within 48 h.Degrease the test area of the test specimen usi
49、ng a suitable organic solvent.NOTE 1 If a silicone or wax preservative has been applied after sealing, degreasing might not be adequate. In such cases, satisfactory cleaning can sometimes be achieved by first using an organic solvent, followed by rubbing with a paste of magnesium oxide or pumice powder and water until no water break occurs.Screw one electrode into the test specimen so that it makes good electrical contact with the basis metal.Carefully fix the cell (5.2) on the test area. If the area of the cell is modified by the geometric sh
