The increase of commodity prices for classical corrosion protection materials such as WC/Co and Cr 3 C 2 /NiCr are leading to significantly increased coating costs. This reduces the competitiveness when compared to other coating technologies such as electroplating, particularly if carbide coatings are representing an over engineered solution for the considered application. A promising economic alternative is the employment of advanced ferrous materials. Fe-base coatings have the potential for very good corrosion protection and favourable wear properties combined with a low cost level due to relatively low priced alloy materials. In this study three different Fe-base materials have been sprayed by liquid and gaseous fuel HVOF spraying and analysed with respect to microstructure, hardness and corrosion resistance. Corrosion tests have been carried out with sulphuric acid as well as artificial seawater.

Structuring coating materials in the nanoscale can significantly enhance the performance of Fe-based coatings. Nanostructured steel coatings with a very high hardness, the strength of carbon-based fibers and a corrosion resistance superior to nickel-based super alloys are currently commercially available. This work deals with the development of wear resistance nanostructured coatings using a commercial steel powder by high frequency pulse detonation. Results concerning the deposition of this powder using two different high velocity oxy-fuel spray systems are presented for comparison. The process parameters were optimized on the basis of the achieved coating features hardness, thickness, porosity and surface roughness. The microstructure of the coatings achieved with the different systems as well as the resulting adhesion and cavitation erosion resistance are compared. These results are also compared with the performance of standard WC-CoCr coatings.