《BS-EN-12373-17-2001.pdf》由会员分享,可在线阅读,更多相关《BS-EN-12373-17-2001.pdf(12页珍藏版)》请在三一文库上搜索。
1、BRITISH STANDARD BS EN 12373-17:2001 Incorporating Amendment No. 1 Aluminium and aluminium alloys Anodizing Part 17: Determination of electric breakdown potential The European Standard EN 12373-17:2001 has the status of a British Standard ICS 25.220.20; 77.120.10 ? BS EN 12373-17:2001 This British S
2、tandard, having been prepared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 July 2001 BSI 30 July 2002 ISBN 0 580 37780 6 National foreword This British Standard is the official Englis
3、h language version of EN 12373-17:2001. It supersedes BS 6161-15:1987 which is withdrawn. The UK participation in its preparation was entrusted to Technical Committee STI/32, Anodic oxidation coatings on aluminium, which has the responsibility to: A list of organizations represented on this committe
4、e can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Sear
5、ch” facility of the BSI Electronic Catalogue. This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to und
6、erstand the text; present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front co
7、ver, an inside front cover, the EN title page, pages 2 to 8, an inside back cover and a back cover. The BSI copyright date displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments 1373030 July 2002Addition of supersession detai
8、ls to national foreword EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 12373-17 May 2001 ICS 25.220.20; 77.120.10 English version Aluminium and aluminium alloys - Anodizing - Part 17: Determination of electric breakdown potential Aluminium et alliages daluminium - Anodisation - Partie 17: Dter
9、mination de la tension lectrique de claquage Aluminium und Aluminiumlegierungen - Anodisieren - Teil 17: Bestimmung der elektrischen Durchschlagspannung This European Standard was approved by CEN on 20 April 2001. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipul
10、ate 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 Management Centre or to any CEN member. This European Standard exist
11、s 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 Management Centre has the same status as the official versions. CEN members are the national standards bodies
12、 of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Man
13、agement Centre: rue de Stassart, 36 B-1050 Brussels 2001 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 12373-17:2001 E Page 2 EN 12373-17:2001 ContentsPage Foreword3 1Scope .5 2Principle.5 3Apparatus.5 4Procedure.6 5Expression of
14、results7 6Test report8 Page 3 EN 12373-17:2001 Foreword This European Standard has been prepared by 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 publicat
15、ion of an identical text or by endorsement, at the latest by November 2001, and conflicting national standards shall be withdrawn at the latest by November 2001. EN 12373, Aluminium and aluminium alloys Anodizing, comprises the following parts: Part 1:Method for specifying decorative and protective
16、anodic oxidation coatings on aluminium Part 2:Determination of mass per unit area (surface density) of anodic oxidation coatings Gravimetric method Part 3:Determination of thickness of anodic oxidation coatings Non-destructive measurement by split beam microscope Part 4:Estimation of loss of absorpt
17、ive power of anodic oxidation coatings after sealing by dye spot test with prior acid treatment Part 5:Assessment of quality of sealed anodic oxidation coatings by measurement of admittance Part 6:Assessment of quality of sealed anodic oxidation coatings by measurement of the loss in mass after imme
18、rsion in phosphoric acid/chromic acid solution without prior acid treatment Part 7:Assessment of quality of sealed anodic oxidation coatings by measurement of the loss in mass after immersion in phosphoric acid/chromic acid solution with prior acid treatment Part 8:Determination of the comparative f
19、astness to ultra-violet light and heat of coloured anodic oxidation coatings Part 9:Measurement of wear resistance and wear index of anodic oxidation coatings using an abrasive wheel wear test apparatus Part 10:Measurement of mean specific abrasion resistance of anodic oxidation coatings using an ab
20、rasive jet test apparatus Part 11:Measurement of specular reflectance and specular gloss of anodic oxidation coatings at angles of 20?, 45?, 60? or 85? Part 12:Measurement of reflectance characteristics of aluminium surfaces using integrating-sphere instruments Page 4 EN 12373-17:2001 Part 13:Measur
21、ement of reflectivity characteristics of aluminium surfaces using a goniophotometer or an abridged goniophotometer Part 14:Visual determination of image clarity of anodic oxidation coatings Chart scale method Part 15:Assessment of resistance of anodic oxidation coatings to cracking by deformation Pa
22、rt 16:Check for continuity of thin anodic oxidation coatings Copper sulfate test Part 17:Determination of electric breakdown potential Part 18:Rating system for the evaluation of pitting corrosion Chart method Part 19:Rating system for the evaluation of pitting corrosion Grid method According to the
23、 CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sw
24、eden, Switzerland and the United Kingdom. Page 5 EN 12373-17:2001 1Scope This Part of this European Standard specifies methods of test for the determination of the electrical breakdown potential of anodic oxidation coatings on aluminium and its alloys on flat or near-flat surfaces and on round wire.
25、 The methods are applicable to anodic oxidation coatings used primarily as electrical insulators. The methods are not applicable to coatings in the vicinity of cut edges, the edges of holes, or sharp changes of angle on, for example, extruded shapes. NOTE 1 The methods described do not give satisfac
26、tory results for unsealed coatings. NOTE 2 Electrical breakdown potential is affected by relative humidity. 2Principle The electric voltage at which current first passes through an anodic oxidation coating is measured; this breakdown potential is a function of the dielectric characteristics and the
27、insulation properties of the oxide coating. The breakdown potential depends upon the thickness of the coating, as well as on many other factors, particularly the composition of the basis metal, its surface condition, the effectiveness of sealing, the dryness of the sample and degree of ageing. 3Appa
28、ratus 3.1 Power supply, from a suitable 50 Hz source. 3.2 a.c. transformer, having an output with a waveform as nearly sinusoidal as possible, capable of producing the potential required. 3.3 Voltage regulator, enabling the test potential to be increased gradually from any point without interruption
29、, and providing an essentially undistorted waveform so that peak potential shall be within the limits 2 5 % (i.e. 1,34 to 1,48) of the r.m.s. potential. 3.4 Current limiting resistor, 0,5 M?, in series with the transformer secondary winding and the test electrode probe (3.6). 3.5 Potential-measuring
30、 device, which gives r.m.s. values, expressed in volts. 3.6 Electrode probe, made from conducting material, suitably insulated for handling purposes, free to move as required and adequately supported. The contact surface shall be spherical with a diameter of 3 mm to 8 mm and shall be maintained in a
31、 smooth, untarnished condition. The design of the probe shall be such that, when the spherical surface is placed on the surface of the anodized test specimen, the total force exerted on the coating is 0,5 N to 1,0 N (a probe of mass 50 g to 100 g is suitable). 3.7 Contact plate, for testing flat tes
32、t specimens, having a smooth, bright, metallic surface, or a contact probe or clip which is capable of breaking through to the basis metal (see 4.2.1). Page 6 EN 12373-17:2001 3.8 Twisting machine, for testing round wire, having two sets of jaws 400 mm apart, with one set of jaws fixed, while the ot
33、her set is free to rotate. The jaws shall be mounted so as to prevent lateral movement of the jaws when the twisting operation is carried out (see 4.2.2). 4Procedure 4.1 Test specimen The test specimen shall normally consist of a production component (or a part thereof). It shall be sealed, dry and
34、clean and, if required, shaped to correspond to its ultimate use in service. Unsealed items may be tested but only under conditions of known, recorded and controlled relative humidity. NOTE The use of specially prepared test specimens, processed at the same time and in the same manner as production
35、articles, can lead to erroneous results. 4.2 Determination 4.2.1 Flat or near-flat surfaces Unless otherwise specified, carry out the determination at room temperature. Measure and record the relative humidity of the environment in which the test is taking place. Place the test specimen on the conta
36、ct plate (3.7) in good electrical contact with it, for example, by using an earthing clip. Alternatively make contact to the basis metal using the contact probe or clip. Connect the contact plate or contact probe or clip (3.7) and the electrode probe (3.6) to opposite poles of the secondary winding
37、of the transformer (3.2) and place the probe on the test specimen so that the force exerted on the coating is 0,5 N to 1,0 N (see 3.6). Starting at zero, increase the potential uniformly at a rate not exceeding 25 V/s until the specified potential is reached or the potential drops suddenly (indicati
38、ng electrical breakdown of the coating). It is necessary to clean the contact surface of the probe after any breakdown has occurred, and it is essential to return the potential to zero after each determination and particularly before cleaning the probe. Carry out a minimum of five tests and record t
39、he lowest value obtained. Alternatively, ascertain whether or not any value falls below a predetermined electrical breakdown potential. Page 7 EN 12373-17:2001 4.2.2 Round wire Unless otherwise specified, carry out the determination at room temperature. Measure and record the relative humidity of th
40、e environment in which the test is taking place. Twist together two suitable lengths of wire using the twisting machine (3.8) so that the number of twists per 50 mm specified in table 1 is achieved. Table 1 - Number of twists for round wire test specimens Diameter of wire d mm Number of twists per 5
41、0 mm 0,2 ? d ? 0,35 0,3 d ? 0,54 0,5 d ? 0,753 0,75 d ? 1,252 1,25 d ? 3,251 3,25 d ? 6,50,5 Ensure that the two lengths of wire are of equal length between the jaws, are under equal tension and are touching in the jaws. Remove the wires from the twisting machine, separate the wires for about 50 mm
42、at each end, and remove the anodic coating from one pair of ends. Join the opposite poles of the secondary winding of the transformer to these exposed ends. Starting at zero, increase the potential uniformly at a rate not exceeding 25 V/s until the specified potential is reached or the potential dro
43、ps suddenly (indicating electrical breakdown of the coating). It is essential to return the potential to zero after each determination, and to maintain the transformer to test specimen contacts. Carry out a minimum of five tests and record the lowest value obtained. Alternatively ascertain whether o
44、r not any value falls below a predetermined electrical breakdown potential. 5Expression of results Express the electric breakdown potential, in volts, as the lowest of the five values recorded. Page 8 EN 12373-17:2001 6Test report The test report shall include at least the following information: a)
45、the type and identification of the product tested; b) the anodizing specification, when applicable; c) a reference to this European Standard; d) the electrical breakdown potential (see clause 5) and, where appropriate, a statement as to whether the electrical breakdown potential conforms to that spe
46、cified for the product; NOTE The minimum acceptable breakdown potential will normally be specified in the relevant product specification. e) the relative humidity of the environment at the time of the test; f) any other relevant information on the tests or the results, including the test temperature
47、 if different from room temperature; g) the date of the test. blank BS EN 12373-17:2001 BSI 389 Chiswick High Road London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK view on standards in Europe and at t
48、he international level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve the quality of our products and ser
49、vices. We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel: +44 (0)20 8996 9000. Fax: +44 (0)20 8996 7400. BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards. Buying standards Orders for all BSI, internatio
链接地址:https://www.31doc.com/p-3739028.html