Surface treatment of metals: material‐immanent techniques and their use for extraordinary façades
Various surface treatments can be applied to metals based on alloy and processing. The results are influenced by the combination of alloys, production, pre‐ and post‐processing, along with the physical and chemical surface treatment. The processes themselves are described in detail in various technical books [1–7]. Nevertheless, there are a number of inaccurate ideas regarding the application of these techniques during project discussions. The challenges lie not in technical possibilities of individual steps. It is rather essential to have a systemic understanding of dependencies and effects as well as a comprehensive approach to material selection, manufacturing processes, surface treatment, protection concepts, assembly constraints, maintenance, recycling and the project‐specific process reliability required.
Especially in façade design with high demands on quality and surface treatment, proposed process chains often do not meet the intended properties and haptics of architects and specifiers. This becomes obvious in the case of copper alloys, their different patination techniques, and the influences of pre‐ and post‐treatment, environmental influences and maintenance. This article therefore summarizes surface treatments suitable for materials, in particular copper alloys as well as steel and stainless steel, lists selected processes and reflects influences from pre‐ and post‐treatment, packaging, transport and maintenance. Finally, selected projects with unique surface treatments and special characteristics are shown.