Coil coating is state of the art for the production of electroplated or hot-dip-plated steel sheets for automobile bodies. Vapour deposition techniques in the coil coating mode are up to now only used industrially for metallizing polymers and for deposition of very thin and barrier coatings on various substrates. In the last years many studies on ion beam assisted deposition (IBAD) coatings on metals and insulators for wear reduction and corrosion protection have been made. However the IBAD deposition of larger areas ( ≥10 cm x 10 cm) is still a major problem. Therefore we have developed a coil coater running inside an IBAD deposition chamber and allowing very flexible deposition modes. Single layers, multilayers and alloy layers can be deposited under ion bombardment on metal strips 30 cm wide. A number of examples dealing with Zn-alloy coatings on low alloy steel are reported: pure Zn-coatings were compared with Zn/Ti-, Zn/Cr-, and Zn/Mn-alloys. In some cases also multilayers of the different metals were studied in both static and dynamic operation modes. The coatings had a thickness of 2-8 um and their corrosion behaviour was investigated by salt spray tests. The micro structure and composition of the coatings was studied by scanning electron microscopy and EDX analysis. The behaviour of the coating/substrate system is discussed in comparison with "state-of the-art" Zn-coatings produced by electro-galvanizing. Generally speaking the performance of the optimised coatings is as good or better as the reference standard.
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