Guide to Stainless Steel Finishes Building Series, Volume 1 GUIDE TO STAINLESS STEEL FINISHES Euro Inox Euro Inox is the European market development associa- Full Members tion for stainless steel. The members of Euro Inox include: Acerinox, •European stainless steel producers www.acerinox.es • National stainless steel development associations Outokumpu, •Development associations of the alloying element www.outokumpu.com industries. ThyssenKrupp Acciai Speciali Terni, A prime objective of Euro Inox is to create awareness of www.acciaiterni.com the unique properties of stainless steels and to further their use in existing applications and in new markets. ThyssenKrupp Nirosta, To assist this purpose, Euro Inox organises conferences www.nirosta.de and seminars, and issues guidance in printed form Ugine & ALZ Belgium and electronic format, to enable architects, designers, Ugine & ALZ France specifiers, fabricators, and end users, to become more Groupe Arcelor, www.ugine-alz.com familiar with the material. Euro Inox also supports technical and market research. Associate Members British Stainless Steel Association (BSSA), www.bssa.org.uk Cedinox, www.cedinox.es Centro Inox, www.centroinox.it Informationsstelle Edelstahl Rostfrei, www.edelstahl-rostfrei.de Informationsstelle für nichtrostende Stähle SWISS INOX, www.swissinox.ch Institut de Développement de l’Inox (I.D.-Inox), www.idinox.com International Chromium Development Association (ICDA), www.chromium-asoc.com International Molybdenum Association (IMOA), www.imoa.info Nickel Institute, www.nickelinstitute.org Polska Unia Dystrybutorów Stali (PUDS), www.puds.com.pl GUIDE TO STAINLESS STEEL FINISHES Content Guide to Stainless Steel Finishes Introduction 2 Third Edition 2005 (Building Series, Vol. 1) Mill Finishes 3 ISBN 2-87997-173-X Mechanically Polished and Brushed Finishes 4 © Euro Inox 2005 Patterned Finishes 8 Dutch version ISBN 2-87997-027-X Bead Blasted Finishes 11 Finnish version ISBN 2-87997-015-6 Electro-Polished Finishes 12 French version ISBN 2-87997-026-1 Coloured Finishes 13 German version ISBN 2-87997-023-7 Electrolytically Coloured Finishes 13 Italian version ISBN 2-87997-024-5 Electrolytically Coloured and Patterned Finishes 14 Polish version ISBN 2-87997-079-2 Organic Coatings 15 Spanish version ISBN 2-87997-025-3 Specialist Decorative Finishes 16 Swedish version ISBN 2-87997-014-8 Annex A: Technical and Practical Aspects 18 Turkish version ISBN 2-87997-161-6 Annex B: EN 10088/2 20 Editor Euro Inox Registered office: 241 route d’Arlon 1150 Luxembourg, Grand Duchy of Luxembourg Phone +352 26 10 30 50 Fax +352 26 10 30 51 Executive office: Diamant Building, Bd. A. Reyers 80, 1030 Brussels, Belgium Phone +32 2 706 82 67 Fax +32 2 706 82 69 Disclaimer E-mail [email protected] Euro Inox has made every effort to ensure that the Internet www.euro-inox.org information presented in this document is technically correct. However, the reader is advised that the materi- Authors al contained herein is for general information purposes David Cochrane, Nickel Development Institute, only.Euro Inox, its members, staff, and consultants, Sidcup, U.K. (Text) specifically disclaim any liability or responsibility for Martina Helzel, circa drei, Munich, Germany loss, damage, or injury, resulting from the use of the (Concept and Layout) information contained in this publication. Acknowledgements Building Master / Architect, Designer / Photographer p.10 above: RWE AG / propeller z / propeller z Cover: Belgacom / Michel Jaspers / Detiffe p.10 below: Railtrack / Nicolas Grimshaw and Partners / Charles Birchmore p.2 above: Ballast Nedam Amstelveen / Zwarts en Jansma / Charles Birchmore p.11 left: Dr. K. / Planung Fahr + Partner PFP / Planung Fahr + Partner PFP p.2 below: Eurostar / Nick Derbyshire Design / Charles Birchmore p.11 right: Industrie- und Handelskammer zu Berlin / p.4 above: RATP / Atelier Bernard Kohn / Denis Sutton Nicolas Grimshaw and Partners / Werner Huthmacher p.4 below: RATP / Antoine Grumbach, Pierre Schaall / Denis Sutton p.12: GbR E. Stöckl, G. Stöckl, A. Brunnmeier / Heene Pröbst + Partner / p.5: Flensburger Sparkasse / Kreor Süd GmbH / Fotostudio Remmer Heene Pröbst + Partner p.6: Belgacom / Michel Jaspers / Detiffe p.13:Galbusera / G. Baroni, G. Genghini, M. Pellacini, Assostudio / Milena Ciriello p.7 above: Ayuntamiento de Elche / Pilar Amoros / Juan José Esteva p.14: Eurodisneyland S.A. / Frank O. Gehry and Associates Inc./ Charles Birchmore p.7 below: Blackstone Group / Sir Howard Robertson / David Cochrane p.15: State Hermitage Museum / Gerard Prins / Henk Prins p.7 background: Etablissement Public du Parc de la Vilette / Adrien Fainsilber / p.16: Esmepuli, S.L. / Esmepuli, S.L. / David Valverde Sonja Krebs p.17:Ostdeutsche Sparkassenakademie / Pysall, Stahrenberg & Partner / p.8: Eurostar / Nicolas Grimshaw and Partners / David Cochrane Lutz Hannemann. p.9: Tomas Kiang / Helmut Richter / Rupert Steiner 1 GUIDE TO STAINLESS STEEL FINISHES Introduction Stainless steels are a family of materials with a unique set of properties. Protected by a chromium oxide film at the surface which is formed by a reaction of the chromium in the steel and the oxygen in the atmosphere, stainless steels require no added surface protection against corrosion. In the event of the surface becoming damaged, the film immediately self repairs in the presence of oxygen. As illustrated later in this brochure this protective layer can be modified by chemical process to produce permanent The columns at Amstel- metallic colours. veen bus station in the Netherlands were clad Stainless steels are ideally suited to building with a pattern rolled stainless steel; an ideal applications. They are readily formable and surface for active pede- weldable and further information on their strian areas. physical properties is given in the European Standard EN 10088 Part 1. Standard mill finishes and mechanically treated surface finishes of appropriate hot In the Eurostar Inter- and cold rolled stainless steels are given in national Railway Station EN 10088 Part 2 in which the designations at Ashford, England, stainless steel panels for surface finishes are given by number, for were extensively used example, 1 for hot rolled, 2 for cold rolled, for the control desks and classified by a combination of number and refreshment area. and letter as 2J. This system provides basic in- formation on process route and description, but not on practical application. The purpose of this guide therefore is to : • show to the architect and designer the wide range of possible surfaces at his/her disposal • provide more detail on the processes involved • provide basic technical advice on their application 2 GUIDE TO STAINLESS STEEL FINISHES Mill Finishes Mill finishes, whether hot or cold rolled, are To maximise resistance to corrosion in the the basic supply condition for all stainless as-supplied condition, mill finish surfaces steel flat products. They are used universally are acid cleaned (pickled) to remove scale for standard building components but are formed during the hot rolling and annealing also the basis for subsequent finishing pro- process. cesses that alter the surface to meet more demanding architectural requirements. Four particular surface designations are im- portant for architectural and building appli- cations. These are: 1D, 2D, 2B and 2R. 1D 2D Hot rolled and annealed, and with the mill scale This is a more refined surface than 1D and is achieved removed, this surface condition is classified as a 1D by cold rolling, heat treating and pickling. The low finish. This surface, which is found on thicker sheets reflective matt surface appearance is suitable for and plate, is slightly coarse with very low reflectivity. industrial and engineering needs but, architecturally, It is primarily used for non-decorative purposes is suitable for less critical aesthetic applications. where the visual appearance is less relevant, for example, in unexposed support systems, and structural applications. 2B 2R This is produced as 2D, but a final light rolling using By bright annealing under Oxygen-free atmospheric highly polished rolls gives the surface a smooth, conditions following cold rolling using polished rolls, reflective, grey sheen. This is the most widely used a highly reflective finish, that will reflect clear surface finish in use today and forms the basis for images, is obtained. This ultra-smooth surface is less most polished and brushed finishes. likely to harbour airborne contaminants or moisture than any other mill finish, and it is easy to clean. 3 GUIDE TO STAINLESS STEEL FINISHES Mechanically Polished and Brushed Finishes The number of additional finishing processes polishing specification which can include a can be minimised by selecting, as the starting surface roughness Ra, and inspection crite- point, the closest mill finish to the desired ria. Reference samples should be prepared end result. to the agreed standard and held by each Applied finishes will have a direct bearing party. on the surface appearance and the environ- mental performance of the material, and should be carefully chosen. Mechanically polished and brushed finishes involve the use of abrasive materials that effectively cut the surface of the steel to some degree. A wide choice of uni-directional finishes is available, depending on the original stainless surface, type and texture of the belts and brushes, and the nature of the polishing process used. To achieve a consistent surface quality, it is advisable to agree with the contractor