EN 4827:2017

Aerospace series - Hexavalent chromium free anodizing of aluminium and aluminium alloys

This European Standard defines the requirements for hexavalent chromium free anodizing of aluminium and aluminium alloys for corrosion protection, bonding and painting.
Hard anodizing is not covered by this European Standard.
The purpose of this European Standard is to give design, quality and manufacturing requirements. It does not give complete in-house process instructions; these shall be given in the manufacturers detailed process instructions.

Luft- und Raumfahrt - Hexavalentes chrom(VI)-freies Anodisieren von Aluminium und Aluminiumlegierungen

Série aérospatiale - Anodisation sans chrome hexavalent de l'aluminium et des alliages d'aluminium

La présente Norme européenne définit les exigences pour l’anodisation sans chrome hexavalent de l'aluminium et des alliages d'aluminium pour la protection contre la corrosion, le collage et la peinture.
La présente Norme européenne ne traite pas de l’anodisation dure.
L’objet de la présente Norme européenne est d’indiquer les exigences de conception, qualité et de fabrication. Elle ne donne pas de gamme de production complète ; ces informations doivent être données dans les instructions des fabricants relatives au procédé.

Aeronavtika - Šestvalentni krom brez eloksacije aluminija in aluminijevih zlitin

Ta evropski standard določa zahteve za šestvalentni krom brez eloksacije aluminija in aluminijevih zlitin za korozijsko zaščito, spajanje in barvanje.
Ta evropski standard ne zajema trde eloksacije.
Namen tega evropskega standarda je določiti zahteve glede zasnove, kakovosti in proizvodnje. Ne podaja popolnih navodil glede internega procesa, ki bodo podana v podrobnih navodilih proizvajalcev glede procesa.

General Information

• Status: Withdrawn
• Publication Date: 14-Feb-2017
• Withdrawal Date: 24-Sep-2019
• ICS: 49.025.20 - Aluminium
• ICS: 49.040 - Coatings and related processes used in aerospace industry
• Technical Committee: ASD-STAN - Aerospace
• Drafting Committee: ASD-STAN/D 4 - Metallic
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Completion Date: 25-Sep-2019
• Ref Project: SIST EN 4827:2017 - Aerospace series - Hexavalent chromium free anodizing of aluminium and aluminium alloys

Relations

• Replaced By: EN 4827:2019 - Aerospace series - Hexavalent chromium free anodizing of aluminium and aluminium alloys
• Effective Date: 02-Oct-2019

Standards Content (Sample)

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Aeronavtika - Šestvalentni krom brez eloksacije aluminija in aluminijevih zlitinLuft- und Raumfahrt - Hexavalentes chromfreies Anodisieren von Aluminium und AluminiumlegierungenSérie aérospatiale - Anodisation sans chrome hexavalent de l'aluminium et des alliages d'aluminiumAerospace series - Hexavalent chromium free anodizing of aluminium and aluminium alloys49.025.99Drugi materialiOther materialsICS:Ta slovenski standard je istoveten z:EN 4827:2017SIST EN 4827:2017en,fr,de01-maj-2017SIST EN 4827:2017SLOVENSKI
STANDARD
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
EN 4827
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Aerospace series æ Hexavalent chromium free anodizing of aluminium and aluminium alloys Série aérospatiale æ Anodisation sans chrome hexavalent de l 5aluminium et des alliages d 5aluminium Luftæ und Raumfahrt æ Hexavalentes chromfreies Anodisieren von Aluminium und Aluminiumlegierungen This European Standard was approved by CEN on
t v September
t r s xä
egulations which stipulate the conditions for giving this European Standard the status of a national standard without any alterationä Upætoædate lists and bibliographical references concerning such national standards may be obtained on application to the CENæCENELEC Management Centre or to any CEN memberä
translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Serbiaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Avenue Marnix 17,
B-1000 Brussels
t r s y CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä EN
v z t yã t r s y ESIST EN 4827:2017

Page European foreword . 3 1 Scope . 4 2 Normative references . 4 3 Purpose of process . 5 4 Terms and definitions . 6 5 Protection system classification . 7 6 Process requirements . 8 7 Engineering requirements . 10 8 Quality requirements . 12 Annex A (normative)
Engineering requirements . 14 Annex B (normative)
Quality requirements . 15 B.1 Quality requirements . 15 B.2 Interpretation of the results of the dye-spot test . 15 Bibliography . 18
EN 2284, Aerospace series — Sulphuric acid anodizing of aluminium and wrought aluminium alloys EN 3665, Aerospace series — Test methods for paints and varnishes — Filiform corrosion resistance test on aluminium alloys EN 4704, Aerospace series — Tartaric-Sulphuric-Acid anodizing of aluminium and aluminium wrought alloys for corrosion protection and paint pre-treatment (TSA) EN 4707, Aerospace series — Acid pickling of aluminium and aluminium alloy without hexavalent chromium EN 6072, Aerospace series — Metallic materials — Test methods — Constant amplitude fatigue testing
EN ISO 2409, Paints and varnishes — Cross-cut test (ISO 2409) EN ISO 9227, Corrosion tests in artificial atmospheres — Salt spray tests (ISO 9227) EN ISO 1463, Metallic and oxide coatings — Measurement of coating thickness — Microscopical method (ISO 1463) EN ISO 2085, Anodizing of aluminium and its alloys — Check for continuity of thin anodic oxidation coatings — Copper sulfate test (ISO 2085) EN ISO 2360, Non-conductive coatings on non-magnetic electrically conductive basis materials — Measurement of coating thickness — Amplitude-sensitive eddy-current method (ISO 2360) EN ISO 9220, Metallic coatings — Measurement of coating thickness — Scanning electron microscope method (ISO 9220) SIST EN 4827:2017

Unsealed (type A) Sealed (type B)
Unpainted Painted Bonding (structural) Unpainted Painted Sulfuric acid
anodizing (SAA) EN 2284 Not applicable Applicable Not applicable Applicable Applicable Thin film sulfuric acid anodizing (TFSAA) Tartaric sulfuric acid anodizing (TSA) EN 4704 Not defined yet with chromate free sealing Boric sulfuric acid anodizing (BSAA) Not applicable Phosphoric acid anodizing (PAA) Applicable Not applicable Sulfuric phosphoric acid anodizing (PSA)
NOTE The formation of oxide layer influences the dimensions of the part and is to be considered for close tolerance parts. 4 Terms and definitions For the purposes of this document, the following terms and definitions apply. 4.1 de-anodizing
process, which removes the anodic oxide 4.2 smut precipitations of alloying elements (e.g. Cu, Fe, Zn, Si) on the surface of parts after a process step normally after alkaline etching step 4.3 Mechanically Disturbed Layer MDL layer that is present at the surface resulting from the rolling process of the material 4.4 pit surface corrosion defect at which the anodic coating is penetrated
Note 1 to entry: Typical characteristics of corrosion pits are:  rounded or irregular or elongated geometry,  comet tail or line or halo that emerges from the cavity,  some corrosion by-products inside pits (on aluminium specimens the by-product may be granular, powdery or amorphous and white, grey or black in colour). To be considered as a corrosion pit, a surface cavity must exhibit at least two of the above characteristics. SIST EN 4827:2017

4.6 alloys all aluminium alloys, that are treated with the chromate free anodizing process in the specific shop 4.7 re-anodizing
repetition of the anodizing process step after complete de-anodizing
4.8 sealing chromate free sealing (of the anodized layers) is applied to close the pores produced by the acid anodizing process.
Note 1 to entry: It is usually applied in hot demineralized water bath with or without additives at different temperatures. Sealing improves the corrosion resistance performance of the anodic film. 4.9. batch unless otherwise specified, it comprises parts of the same type (i.e. shape, size, material), processed at the same time in the same bath
5 Protection system classification 5.1 System types Anodizing layer is classified by the two following types:  Type A: unsealed anodizing: It shall be used as surface preparation before the application of painting/ bonding or any other finish.  Type B: sealed anodizing: It is intended for corrosion protection. It shall be with or without dyeing and used with or without additional painting. 5.2 Layer thicknesses See Table 2. Table 2 — Layer thicknesses corresponding to the class type Class type Typical thickness Anodizing process Class 1
¶
s
Ám Phosphoric acid anodizing (PAA) Sulfuric phosphoric acid anodizing (PSA) a
Class 2
t
Ám to
z
Ám Tartaric sulfuric acid anodizing (TSA) Boric sulfuric acid anodizing (BSAA) Thin film sulfuric acid anodizing (TFSAA) Class 3
z
Ám to
t w
Ám Sulfuric acid anodizing (SAA) a
¶
w
Ám for some Aluminium alloys under agreement between purchaser and supplier. SIST EN 4827:2017

6 Process requirements 6.1 Information for the processor  type and class designation,  substrate standard reference and heat treatment,  areas to be anodized,  anodized thickness measuring points,  electrical contact points or areas where these are inadmissible,  specification for testing on parts and/or samples. 6.2 Condition of parts prior to the treatment Welding, soldering/brazing, mechanical operations and heat treatments shall have been completed.  the parts shall be free of oil, grease, marking inks and other surface contaminations;  the surface shall be free from precipitations or smut from alloying elements or pre-processes indicated by the bright and uniform appearance of the surface;  mechanically disturbed layer shall be removed either by mechanical or chemical processes;  in case of re-anodizing all residuals from the previous anodizing shall be completely removed. 6.3 Process conditions 6.3.1 Tooling
The tools, bars, electrical contact systems, and metal masking tooling must be free of corrosion or any other damage which may be detrimental to the treatment during use. The part racks and tools must be designed and set up in such a manner as to:  avoid any retention of air or treatment solution in the parts,  facilitate neutralization and removal of solutions during rinsing operations,  the electrical contacts must be kept in good condition for the correct passage of the current  avoid any accidental contact between the parts to be treated and the tank equipment or electrodes, and between the different parts during all the process.  electrical contact points should be defined between purchaser and processor;  the fixturing tools (e.g. in
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