Development of Nanostructured Iron Based Alloys with Improved Corrosion Resistance for Thermal Spray Applications

In the field of corrosion protection the use of iron based spray materials represents a cost-effective alternative to established materials like nickel based alloys.  

So far large-scale application of iron based coating systems in the field of corrosion protection has been prevented by initially insufficient properties of the coatings in terms of corrosion resistance. At this point the introduction of nanotechnology like the use of amorphous or nanocrystalline materials is seen as one way that can help to enhance corrosion resistance of iron based spray materials and coatings.

With taking the requirement profile for a ductor used in printing machines as an example the aim of this work is the development of a suitable iron alloy that can be used as a spray material for thermal spray applications. The focus of the alloy development lies on compositions that are able to solidify in a nanostructured state and that show improved corrosion resistance. In the first step melting experiments were performed based on several alloy compositions in the alloy system Fe-(Cr, Al)-B. Furthermore the influence of additional alloy elemements like Si, Mo, or Y was investigated. In order to determine the passivity of the considered alloy compositions potential polarization measurements were performed and compared.