Corrosion Behavior of FeCr-TiC-Coatings for Sustainable Brake Discs

The automotive industry is redesigning brake systems in order to fulfill environmental standards and to reduce emissions of brake abrasion. By using wear resistant Fe-based coatings on gray cast iron CO2- and particle emissions can be decreased and recycling of coated brake discs can be facilitated. Yet Fe-based alloys are prone to corrosion. This study examines the corrosion behavior of a FeCr-TiC-coating with 45.5 % mass fraction of TiC and a reduced Nickel content of only 3 % on the typical brake disc material EN GJL 250C. The coating is produced using high velocity oxygen fuel spraying (HVOF). The current density potential curve shows that the FeCr-TiCcoating improves the corrosion resistance of the gray cast iron disc by a factor of 9. After salt spray testing, the coated gray cast iron discs show fewer corrosion products on the surface when compared to the uncoated base material.