Metallic ions in a normally watery metal salt solution are separated from the solution by using metallic building components – which are to be layered – as the cathode. In order to get this type of coating on building components, electroplating is utilized. However in the case of iron, this galvanic separation is a relatively elaborate procedure, as it is characterized by a low efficiency factor and often fails to produce the desired surface quality. Ionic liquids offer an alternative.
The Research Institute for Precious Metals and Metallic Chemistry in Schwäbisch Gmünd, in cooperation with the Fraunhofer Institute for Chemical Technology (ICT) in Pfinztal, IPT International Plating Technologies GmbH in Stuttgart, and the IoLiTec GmbH of Heilbronn, has developed a procedure by which iron is separated from such ionic liquids. Iron salts are dissolved in an organic molten salt which is liquid at room temperature.
In attempts with different ionic liquids, a choline chloride-urea-FeCl3 mixture showed an especially advantageous separation behavior for iron. The iron coatings manufactured this way also proved highly corrosion-resistant. A possible application for the new coating procedure may be with diffusion barrier layers, which are often still made of nickel.
Project Operation:
fem Forschungsinstitut
Edelmetalle & Metallchemie
Katharinenstr. 17
73525 Schwäbisch Gmünd
Telefon 07171|1006-0
fem@fem-online.de
www.fem-online.de
Cooperation Partner:
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