DIN EN 12487-2007 Corrosion protection of metals - Rinsed and non-rinsed chromate conversion coatings on aluminium and aluminium alloys English version of DIN EN 12487 2007-07《金属的腐.pdf

1、July 2007DEUTSCHE NORM English price group 10No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 25.220.40!,z(N“9870543www

2、.din.deDDIN EN 12487Corrosion protection of metals Rinsed and non-rinsed chromate conversion coatings on aluminium andaluminium alloysEnglish version of DIN EN 12487:2007-07Korrosionsschutz von Metallen Gesplte und no-rinse Chromatierberzge auf Aluminium und AluminiumlegierungenEnglische Fassung DIN

3、 EN 12487:2007-07SupersedesDIN EN 12487:2000-07 andDIN 50939:1996-09www.beuth.deDocument comprises 18 pages 09.07DIN EN 12487:2007-07 2 National foreword This standard has been prepared by CEN/TC 262 “Metallic and other inorganic coatings”, the Secretariat of which is held by BSI (United Kingdom). T

4、he responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing Standards Committee), Technical Committee NA 062-01-72 AA Chemische und elektro-chemische berzge. Amendments This standard differs from DIN EN 12487:2000-07 and DIN 50939:1996-09 as follo

5、ws: a) In Table 1, conversion coating types C2 and E2 have been deleted and a note concerning chromated long coils has been added. b) The standard designation has been amended. c) In Annex A, a maximum drying temperature for an after-treatment, as measured on the metal surfaces, of 100 C has been sp

6、ecified and Figure A.1 has been amended accordingly. Table A.1 has been deleted. d) Annex E has been deleted. e) Since most of the specifications of DIN 50939:1996-09 are included here, NA 062-01-72 AA decided to withdraw the former standard. Previous editions DIN EN 12487: 2000-07 DIN 50939: 1976-0

7、1, 1988-04, 1996-09 EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN 12487April 2007ICS 25.220.40 Supersedes EN 12487:2000 English VersionCorrosion protection of metals - Rinsed and non-rinsedchromate conversion coatings on aluminium and aluminiumalloysProtection contre la corrosion des mtaux - Cou

8、ches deconversion au chromate rinces et non rinces surlaluminium et les alliages daluminiumKorrosionsschutz von Metallen - Gesplte und no-rinseChromatierberzge auf Aluminium undAluminiumlegierungenThis European Standard was approved by CEN on 24 February 2007.CEN members are bound to comply with the

9、 CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nationalstandards may be obtained on application to the CEN Management Centre or

10、 to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as theofficial versio

11、ns.CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Romania, Slovakia, Slovenia, Spain,

12、 Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2007 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members

13、.Ref. No. EN 12487:2007: EEN 12487:2007 (E) 2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Information to be supplied by the purchaser .5 4 Coating types and designation 5 4.1 Coating types .5 4.2 Conversion coating designation6 5 Sampling.6 6 Coating requirements7 6.1 General7 6.2 E

14、lectrical insulation.7 6.3 Adhesion.7 6.4 Coating mass per unit area.7 6.5 Coating identification 7 6.6 Corrosion resistance.8 Annex A (informative) Process systems.9 Annex B (normative) After-treatments.12 Annex C (normative) Analytical methods for the determination of the coating mass and for the

15、identification of chromium, phosphorus and zinc .13 Annex D (normative) Testing of the layer composition.14 Bibliography 16 EN 12487:2007 (E) 3 Foreword This document (EN 12487:2007) has been prepared by Technical Committee CEN/TC 262 “Metallic and other inorganic coatings”, the secretariat of which

16、 is held by BSI. 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 October 2007, and conflicting national standards shall be withdrawn at the latest by October 2007. This document supersedes EN 1248

17、7:2000. 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, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland,

18、 Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EN 12487:2007 (E) 4 1 Scope This European Standard specifies requirements for rinsed and non-rinsed chromate conversion coatings on alumini

19、um and aluminium alloys intended to protect against corrosion and serve as a base for other coatings. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the la

20、test edition of the referenced document (including any amendments) applies. EN 485-1, Aluminium and aluminium alloys - Sheet, strip and plate - Part 1: Technical conditions for inspection and delivery EN 485-2, Aluminium and aluminium alloys - Sheet, strip and plate - Part 2: Mechanical properties E

21、N 485-3, Aluminium and aluminium alloys - Sheet, strip and plate - Part 3: Tolerances on dimensions and form for hot-rolled products EN 485-4, Aluminium and aluminium alloys - Sheet, strip and plate - Part 4: Tolerances on shape and dimensions for cold-rolled products EN 515, Aluminium and aluminium

22、 alloys Wrought products Temper designations EN 573-1, Aluminium and aluminium alloys Chemical composition and form of wrought products Part 1: Numerical designation system EN 573-2, Aluminium and aluminium alloys Chemical composition and form of wrought products Part 2: Chemical symbol based design

23、ation system EN 573-3, Aluminium and aluminium alloys Chemical composition and form of wrought products Part 3: Chemical composition EN ISO 3892, Conversion coatings on metallic materials Determination of coating mass per unit area Gravimetric methods (ISO 3892:2000) EN ISO 9227, Corrosion tests in

24、artificial atmospheres Salt spray tests (ISO 9227:2006) ISO 4519, Electrodeposited metallic coatings and related finishes Sampling procedures for inspection by attributes IEC 60603-1, Connectors for frequencies below 3 MHz for use with printed boards - Part 1: Generic specification - General require

25、ments and guide for the preparation of detail specifications, with assessed quality (IEC 60603-1:1991 + A1:1992) 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1 rinsed chromate coating chromate coating that is rinsed in water prior to drying

26、EN 12487:2007 (E) 5 NOTE This type of coating is typically applied to extruded and rolled aluminium fabricated parts, castings and long coils. 3.2 non-rinsed chromate coating coil coating chromate coating that is dried immediately after the chromating step without receiving a water rinse NOTE This t

27、ype of coating is normally used on long coils of aluminium sheet stock that receive immediate painting or adhesive coating. 4 Information to be supplied by the purchaser The following information shall be supplied by the purchaser: a) coating designation (see clause 5); b) sampling methods, acceptan

28、ce levels or any other inspection requirements if different from those given in ISO 4519 (see clause 6); c) surface preparation prior to chromate conversion coating (see Annex A for guidance); d) requirements for adhesion (see 7.3) and corrosion resistance (see 7.6); e) nature, condition and finish

29、of the basis metal, if any of these could affect the serviceability and/or appearance of the coating. WARNING Use of this standard can involve hazardous materials, operations and equipment. This standard does not purport to address all the safety problems associated with its use. It is the responsib

30、ility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Chemicals and materials shall be used and disposed of in a professional and environmentally suitable manner. 5 Coating types and designation

31、 5.1 Coating types A conversion coating shall be referred to as type A, type C1, or type E1 in accordance with Table 1. NOTE Annex A provides guidance on coating type, purpose, end use and mass per unit area. EN 12487:2007 (E) 6 Table 1 Types of chromate conversion coating Type Appearance Coating ma

32、ss per unit area(g/m) Other properties A Colourless 0,05 to 0,2 Decorative, low insulation resistance C1 Yellow (light to iridescent) 0,4 to 1,0 Used as a paint base and for bonding to rubber E1 Light green 0,4 to 1,2 Used as a paint base and for bonding to rubber NOTE For chromated long coils for t

33、ypes C1 and E1, the coating mass 0,5 g/m2to 0,8 g/m2is recommended. 5.2 Conversion coating designation The conversion coating designation shall be comprised of the following: a) number of this European Standard; b) hyphen; c) aluminium alloy designation in accordance with EN 573-1, EN 573-2 and EN 5

34、73-3 (wrought aluminium alloys), EN 485 parts 1 through 4 (cast aluminium alloys) and the temper designation in accordance with EN 515; d) solidus; e) symbol designating the type of coating (see Table 1 and NOTE 1 below). If the chromate conversion coating has to be after-treated, the designation sh

35、all also be comprised of the following: f) solidus; g) symbol indicating any after-treatment of the conversion coating as specified in Table B.1, Annex B (also see NOTE 2 below). NOTE 1 It is recommended that the chemical symbol is followed by the standard designation of the basis metal. NOTE 2 This

36、 can be repeated if more after-treatments are required. EXAMPLE The designation of a chromate conversion coating with a coating mass of 0,4 g/m2to 1,2 g/m2(E1) on wrought aluminium alloy EN AW-6060 T6, that has been after-treated with the application of inorganic or organic sealant (T2) is: Chromate

37、 conversion coating EN 12487-EN AW 6060 T6/E1/T2. 6 Sampling Sampling shall either be carried out in accordance with ISO 4519 or as specified by the purchaser (see clause 4, b). EN 12487:2007 (E) 7 7 Coating requirements 7.1 General Any tests (including corrosion resistance tests) shall be deferred

38、until the expiry of a 24 h period after treatment. NOTE Conversion coatings harden with age by gradual dehydration; they should, therefore, be handled carefully for the first 24 h after the last treatment. 7.2 Electrical insulation When measured at an open circuit voltage of 9 V and a current of 2 A

39、 in accordance with IEC 60603-1, the resistance between an electrical contact and the aluminium shall be less than 0,1 for type A, type C1 and type E1 coatings. 7.3 Adhesion 7.3.1 The coatings shall be adherent and non-powdery. The conversion coating shall pass the test described in 7.3.2 or 7.3.3.

40、7.3.2 Rub the dried surface with white soft tissue paper using normal hand pressure, making 10 movements. This treatment shall not leave any trace of staining on the paper. 7.3.3 If the test described in 7.3.2 is not sufficient to measure the adhesion of a conversion coating on aluminium, carry out

41、a practical evaluation of the adhesion by measuring the adhesion of a secondary organic film applied to the chromated aluminium. 7.4 Coating mass per unit area For all but thin (type A) coatings, the coating mass per unit area of chromate and chromate-phosphate coatings on aluminium shall be determi

42、ned in accordance with EN ISO 3892 or with the methods described in C.2 to C.4. For thin (type A) chromate coatings, the coating mass per unit area shall be determined in accordance with C.3 and C.4. NOTE For thin chromate coatings, the errors associated with the methods described in EN ISO 3892 are

43、 unacceptably high. 7.5 Coating identification 7.5.1 General The test methods specified in Annex D shall be used to determine the presence or absence of relevant chemical elements in the conversion coating. 7.5.2 Chromate conversion coatings (yellow) The presence of chromium and the absence of phosp

44、hate in the coating shall identify the layer as a chromate conversion coating. The layer may contain hexavalent chromium. 7.5.3 Chromate phosphate coatings (green) The presence of phosphate and chromium and the absence of zinc shall identify the layer as a chromate-phosphate conversion coating. The

45、layer consists of trivalent chromium. EN 12487:2007 (E) 8 7.6 Corrosion resistance The corrosion resistance of a conversion coating shall be determined in accordance with EN ISO 9227. NOTE Requirements for corrosion resistance of conversion coatings vary widely depending on the aluminium alloys to w

46、hich they are applied. The method is only suitable for production control to show no changes in the coating process during pre-treatment or between different periods of pre-treatment. EN 12487:2007 (E) 9 Annex A (informative) Process systems A.1 Surface preparation The surfaces of the parts to be ch

47、romated should be clean and substantially free from any oxidation, scale or soils such as metal turnings, grinding dust, oil, grease, lubricants, hand-sweat or any other contamination that is detrimental to the final finish. The parts should therefore be cleaned before chromating and if necessary, b

48、e pickled. Prior to the non-rinsed chromating process, surfaces should be free from non-reactive soluble salts. Care should be taken when rinsing to avoid splattering of chemicals and corrosion initiation. Figure A.1 shows the processing step options available depending on the preparation and intend

49、ed end use required. EN 12487:2007 (E) 10 Degreasing Aqueous acid solution Aqueous alkaline solution Aqueous organic solution Organic solvents Cold water rinse Pickling (de-oxidizing-matt pickling burnishing) (acid) Pickling (de-oxidizing - matt pickling burnishing) (alkaline) Neutralization Cold water rinse Cold water rinse Brightening (nitric acid plus hydrofluoric acid) Cold water rinse Chromating Green Colourless - yellowCold water rinse Hot water rinse (below 60 C) Drain water 30 S/cm 1Drying (metal surface tempera