Large area IBAD deposition of Zn-alloys in the coil coating mode

In the last years many studies on IBAD coatings on metals and insulators fo r wear reduction and corrosion protection have been published. However the IBAD deposition of larger areas (> 10 x 10 cm) is still a major problem. Th erefore we have developed a coil coater running inside the IBAD deposition chamber and allowing very flexible deposition modes. Single layers, multila yers and alloys can be deposited under ion bombardment on substrates up to 30 by 40 cm or on metal and polymer strips 30 cm wide. A number of tramples dealing with Zn-alloy coatings on low alloy steel are reported: pure Zn-co atings were compared with Zn/Ti-alloys Zn/Cr-alloys and Zn/Mn-alloys. In so me cases also multilayers of the different metals were studied in the stati c and dynamic operation mode. The coatings had a thickness of 2-8 muM and t heir corrosion behaviour was investigated by salt spray tests. The microstr ucture of the coatings was studied by electron microscopy and EDX-deprh pro filing. The behaviour of the coating/substrate system is discussed in compa rison with "state-of-the-art" Zn-coatings produced by electrogalvanizing. G enerally speaking the performance of the optimized coatings was as good as or better than the electrogalvanized standard. (C) 2001 Elsevier Science B. V. All rights reserved.