1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 2931:2010Anodizing of aluminium and itsalloys Assessment of qualityof sealed anodic oxidationcoatings by measurement ofadmittance (ISO 2931:2010)BS EN ISO 2931:2010 BRI
2、TISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 2931:2010.It supersedes BS EN 12373-5:1999 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee STI/32, Anodic oxidation coatings on aluminium.A list of organizations repr
3、esented on this committee can beobtained on request to its secretary.This publication does not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2010ISBN 978 0 580 66000 9ICS 25.220.20Compliance with a British Standard cannot confer i
4、mmunity fromlegal obligations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 August 2010.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 2931 July 2010 ICS 25.220.20 Supersedes
5、EN 12373-5:1998English Version Anodizing of aluminium and its alloys - Assessment of quality of sealed anodic oxidation coatings by measurement of admittance (ISO 2931:2010) Anodisation de laluminium et de ses alliages - valuation de la qualit des couches anodiques colmates par mesurage de ladmittan
6、ce (ISO 2931:2010) Anodisieren von Aluminium und Aluminiumlegierungen - Prfung der Qualitt von verdichteten, anodisch erzeugten Oxidschichten durch Messung des Scheinleitwertes (ISO 2931:2010) This European Standard was approved by CEN on 2 June 2010. CEN members are bound to comply with the CEN/CEN
7、ELEC 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 obtained on application to the CEN Management Centre or to an
8、y 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 Management Centre has the same status as the official versions.
9、 CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Sloveni
10、a, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN nati
11、onal Members. Ref. No. EN ISO 2931:2010: EBS EN ISO 2931:2010EN ISO 2931:2010 (E) 3 Foreword This document (EN ISO 2931:2010) has been prepared by Technical Committee ISO/TC 79 “Light metals and their alloys“ in collaboration with Technical Committee CEN/TC 132 “Aluminium and aluminium alloys” the s
12、ecretariat 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 endorsement, at the latest by January 2011, and conflicting national standards shall be withdrawn at the latest by January 2011. Attention i
13、s drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 12373-5:1998. According to the CEN/CENELEC Internal Regulations, the
14、national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherla
15、nds, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 2931:2010 has been approved by CEN as a EN ISO 2931:2010 without any modification. BS EN ISO 2931:2010ISO 2931:2010(E) ISO 2010 All rights reserved iiiCon
16、tents Page Foreword iv Introduction.v 1 Scope1 2 Normative references1 3 Terms and definitions .1 4 Principle2 5 Apparatus and materials.2 6 Test pieces .2 7 Procedure.2 8 Expression of results3 9 Test report4 Bibliography5 BS EN ISO 2931:2010ISO 2931:2010(E) iv ISO 2010 All rights reservedForeword
17、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 which a technical
18、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 collaborates closely with the International Electrotechnical Commission (IEC) on all matters of elect
19、rotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the
20、member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn 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 ident
21、ifying any or all such patent rights. ISO 2931 was prepared by Technical Committee ISO/TC 79, Light metals and their alloys, Subcommittee SC 2, Organic and anodic oxidation coatings on aluminium. This third edition cancels and replaces the second edition (ISO 2931:1983), which has been technically r
22、evised. BS EN ISO 2931:2010ISO 2931:2010(E) ISO 2010 All rights reserved vIntroduction The test described in this International Standard is intended to give a quick, non-destructive assessment of the quality of sealed anodic oxidation coatings and is very suitable for routine production control. It
23、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 sealing tests may be affected by the presence of sealing additives, or contaminants such as silicate or ph
24、osphate. For this reason, sealing quality is checked from time to time by one of the reference acid-dissolution methods specified in ISO 3210. The pretreatment, the anodizing process, the colouring process used and the alloy can all have an effect on admittance readings. BS EN ISO 2931:2010BS EN ISO
25、 2931:2010INTERNATIONAL STANDARD ISO 2931:2010(E) ISO 2010 All rights reserved 1Anodizing of aluminium and its alloys Assessment of quality of sealed anodic oxidation coatings by measurement of admittance 1 Scope This International Standard specifies a method for assessing the quality of sealed anod
26、ic 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. The method is suitable for use as a production-control test and as an acceptance test where there is agreement between the supplier a
27、nd 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 greater than 3 m. 2 Normative references The following referenced documents are indispensable for the appl
28、ication of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 2360, Non-conductive coatings on non-magnetic electrically conductive basis materials Measurement of coating t
29、hickness Amplitude-sensitive eddy-current method 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 admittance Y inverse of the complex apparent resistance, Z 1Y Z= NOTE In an alternating current circuit, Z (impedance) is represented by the vect
30、orial sum of actual resistance, R, and the reactance, Xcusing Equation (1). 22cX RZ =+ (1) where R is the resistance, in ohms; Xc= 12 f Cis the reactance; BS EN ISO 2931:2010ISO 2931:2010(E) 2 ISO 2010 All rights reservedwhere f is the frequency of the alternating current; C is the capacitance. 4 Pr
31、inciple An anodic oxidation coating on aluminium is represented as an electrical diagram made up of a number of ohmic and capacitative resistances mounted in series and/or parallel in an alternating-current circuit. The numerical value of these resistances depends upon the following variables: a) ba
32、sis metal (for example, composition, size and distribution of intermetallic compounds, and surface condition); b) type of sealing process (for example, steam, hot water, nickel or cobalt salts or cold sealing); c) thickness and density of the anodic oxidation layer (depending upon electrolyte, type
33、of current, current density, electrolyte temperature, etc.); d) dyeing or pigmentation processes used to colour the anodic oxidation coating; e) time and conditions of storage between sealing and measurement. 5 Apparatus and materials 5.1 Device for measuring admittance, covering a range of 3 S to 3
34、00 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 sample, and the other with a pencil-like probe. 5.2 Cell, containing the electrolyte, formed conv
35、eniently 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. 5.3 Electrolyte, aqueous solution of potassium sulfate, 35 g/l. 6 Test pieces Anodized products of any shape or dimension,
36、provided that it is possible to determine the thickness of the coating at the point of measurement, to apply the electrolyte-filled cell and, if necessary, to determine the surface area tested. 7 Procedure Carry out the test preferably within 1 h to 4 h after sealing and cooling to room temperature,
37、 and, in any case within 48 h. Degrease the test area of the test piece using a suitable organic solvent. NOTE 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
38、solvent, followed by rubbing with a paste of magnesium oxide or pumice powder and water until no water break occurs. BS EN ISO 2931:2010ISO 2931:2010(E) ISO 2010 All rights reserved 3Screw one electrode into the test piece so that it makes good electrical contact with the basis metal. Carefully fix
39、the cell (5.2) on the test area. If the area of the cell is modified by the geometric shape of the test piece, determine the new dimensions. Fill the cell with the electrolyte (5.3). At each point of measurement, use a new cell and fresh electrolyte. If the test is carried out on an oblique or verti
40、cal surface, introduce into the cell a cotton-wool plug soaked in the electrolyte, or use a cell of special design. Immerse the other electrode in the solution and measure the admittance. Carry out the measurement at a temperature between 10 C and 35 C. Take the reading at least 2 min after the intr
41、oduction of the electrode into the cell, and record the temperature. After the admittance has been measured, determine the thickness of the anodic coating at the point of measurement using the method described in ISO 2360. NOTE Cells which are not perfectly attached, and therefore not watertight, wi
42、ll give an inaccurate reading. 8 Expression of results To allow comparison of results, the result recorded shall include three corrections to the measured value: a) a correction to relate the measured admittance value to a measuring area of 133 mm2(in the case where it is not possible to use this ex
43、act area, and if the actual measuring area is between 100 mm2and 200 mm2); b) a correction to relate the measured admittance value to that measured at an ambient temperature of 25 C; c) a correction to relate the measured admittance value to a conventional layer thickness of 20 m. Perform these corr
44、ections using Equations (2), (3) and (4): m1133YYA= (2) 211YYf= (3) 2320YeY = (4) where Ymis the measured admittance value, in microsiemens; A is the measuring area, in square millimetres; Y3is the corrected admittance value, in microsiemens; e is the thickness of the anodic oxidation coating, in mi
45、crometres; f1is a coefficient given as a function of the temperature, t, in degrees Celsius, in Table 1. Table 1 Coefficient f1as a function of the temperature t t, C 10 12,5 15 17,5 20 22,5 25 27,5 30 32,5 35 f11,30 1,25 1,20 1,15 1,10 1,05 1,00 0,95 0,90 0,85 0,80 BS EN ISO 2931:2010ISO 2931:2010(
46、E) 4 ISO 2010 All rights reserved9 Test report The test report shall include at least the following information: a) a reference to this International Standard (ISO 2931:2010); b) the type and identification of the product tested; c) the result of the test (see Clause 8); d) the measuring area (if it
47、 is not exactly 133 mm2); e) the temperature at which the test was carried out (if it is not 25 C); f) any deviation from the procedure described in this International Standard; g) the date of the test. BS EN ISO 2931:2010ISO 2931:2010(E) ISO 2010 All rights reserved 5Bibliography 1 ISO 3210, Anodiz
48、ing of aluminium and its alloys Assessment of quality of sealed anodic oxidation coatings by measurement of the loss of mass after immersion in phosphoric acid/chromic acid solution This page deliberately left blankThis page deliberately left blankBSI is the independent national body responsible for
49、 preparing British Standardsand other standards-related publications, information and services. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.British Standards Institution (BSI)raising standards worldwideBSI Group Headquarters389 Chiswick High Road London W4 4AL UKTel +44 (0)20 8996 9001Fax +44 (0)20 8996 Standards are updated by amendment or revision. Users of British Stan-dards should make sure that th
