EN 4827:2024

SLOVENSKI STANDARD
01-september-2024
Aeronavtika - Šestvalentni krom brez eloksacije aluminija in aluminijevih zlitin
Aerospace series - Hexavalent chromium free anodizing of aluminium and aluminium
alloys
Luft- und Raumfahrt - Anodisieren von Aluminium und Aluminiumlegierungen ohne
hexavalentem Chrom
Série aérospatiale - Anodisation sans chrome hexavalent de l'aluminium et des alliages
d'aluminium
Ta slovenski standard je istoveten z: EN 4827:2024
ICS:
49.025.99 Drugi materiali Other materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN 4827
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2024
EUROPÄISCHE NORM
ICS 49.025.20; 49.040 Supersedes EN 4827:2019
English Version
Aerospace series - Hexavalent chromium free anodizing of
aluminium and aluminium alloys
Série aérospatiale - Anodisation sans chrome Luft- und Raumfahrt - Chrom(VI)-freies Anodisieren
hexavalent de l'aluminium et des alliages d'aluminium von Aluminium und Aluminiumlegierungen
This European Standard was approved by CEN on 5 May 2024.

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 obtained 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-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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2024 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 4827:2024 E
worldwide for CEN national Members.

Contents Page
European foreword . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
3.1 General terms . 7
3.2 Technical terms . 7
4 General principles of the process . 9
4.1 Purpose of the process . 9
4.2 Applicability . 9
4.2.1 Type A: unsealed anodizing . 9
4.2.2 Type B: sealed anodizing . 9
4.3 Limitations . 10
4.4 Classification. 10
4.4.1 System types . 10
4.4.2 Layer thickness . 11
5 Process requirements . 11
5.1 Information for the processor . 11
5.2 Process conditions . 11
5.2.1 Tooling . 11
5.2.2 Masking . 12
5.2.3 Surface preparation . 12
5.2.4 Anodizing . 12
5.2.5 Anodizing post-treatments . 12
5.3 Water quality . 13
5.3.1 General. 13
5.3.2 Anodizing bath . 13
5.3.3 Sealing and dyeing baths . 13
5.3.4 Final rinsing bath . 13
5.4 Periodic bath chemical analysis . 13
5.5 Re-anodizing . 14
6 Test specimen requirements . 14
6.1 Definition of test specimens. 14
6.1.1 General. 14
6.1.2 For the qualification . 14
6.1.3 For periodic tests . 14
6.2 Tests for the qualification. 18
6.3 Periodic tests . 18
7 Parts requirements . 18
7.1 Condition of parts prior to the treatment . 18
7.2 Inspections before the treatment . 19
7.3 Inspections during the treatment . 19
7.4 Inspections on parts after anodizing . 19
8 Quality assurance . 19
8.1 Process approval. 19
8.2 General points . 19
8.3 Qualification procedure . 20
Annex A (normative) Tests on test specimens for the qualification . 21
Annex B (normative) Periodic tests on test specimens . 25
Annex C (normative) Levels of requirements for corrosion resistance of thin film anodizing
on unpainted test specimens . 29
Annex D (normative) Tests on parts . 30
Annex E (normative) Dye-spot test . 31
E.1 Dye-spot . 31
E.2 Dye solution A . 31
E.3 Dye solution B . 31
Bibliography . 33

European foreword
This document (EN 4827:2024) has been prepared by the Aerospace and Defence Industries
Association of Europe — Standardization (ASD-STAN).
After enquiries and votes carried out in accordance with the rules of this Association, this document has
received the approval of the National Associations and the Official Services of the member countries of
ASD-STAN, prior to its presentation to CEN.
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 2025, and conflicting national standards shall
be withdrawn at the latest by January 2025.
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 such patent rights.
This document supersedes EN 4827:2019.
This document includes the following significant technical changes with respect to EN 4827:2019:
— normative references have been updated;
— Figure 1 and Figure 2 were added to 3.2.4;
— Clause 6 “Engineering requirements” has been restructured into the new Clause 6 “Test specimens
requirements” and Clause 7 “Parts requirements”;
— requirements relating to the test specimens materials, numbers, dimensions and periodicity have
been included in Table 3 to Table 8;
— requirements for the definition of test specimens for the qualification have been changed and added
to Table 3 to Table 5;
— requirements for the definition of periodic tests have been changed and added to Table 6 to Table 8;
— Annex A has been renamed;
— in Table A.1, changes were made or added to the items: “visual appearance”, “anodic layer
thicknesses”, “corrosion resistance”, “paint adhesion” and “sealing quality”;
— Annex B has been renamed;
— in Table B.1, changes were made to the items “visual appearance”, “anodic layer thicknesses”,
“corrosion resistance” and “paint adhesion”;
— Table C.1 has been added concerning levels of requirements for corrosion resistance of thin film
anodizing on unpainted test specimens;
— in Table D.1, changes were made to the item “visual appearance”;
— document has been revised editorially.
Any feedback and questions on this document should be directed to the users’ national standards
body. A complete listing of these bodies can be found on the CEN website.
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, Finland, France, Germany, Greece, Hungary,
Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Sp
...