ICMCB, University of Bordeaux, France
Title: Nano structuration of thin films an alternative solution for hard chromium coating replacement
Biography: Angeline Poulon-Quintin
Hard chrome plating is used by Original Equipment Manufacturer to provide sealing surface for hydraulic seals, wear resistance to moving parts and corrosion protection to a wide variety of components for aircraft. The main areas of hexachromium using processes are mechanical, automotive, aerospace and military. By improving tribological properties (superior hardness) and corrosion resistance (natural ability to react with element such as oxygen), hard chromium can lower energy consumption of moving parts and machinery, reduce the need to replace parts frequently, leading to reduce waste and improve efficiency. The hard chrome plating is a powerful, simple and cheap process. From an environmental point of view, this process itself involves the use of highly toxic substances, such Cr6+ and lead compounds The Restriction of Hazardous substances Directive (Reach) was issue, banning several toxic substances including Cr6+. Hard chromium electroplating has been also classified by the U.S. Environmental Protection Agency (EPA) as an environmentally unfriendly process. Now, several hard chrome plating alternatives have been developed depending on the application:1) High Velocity Oxy-Fuel thermal sprays for repairs and for the deposition of high-quality hard-metals and metals coatings, 2) Electro and electroless plates; 3) Vacuum coating, 4) Heat treatments, 5) Laser and weld coatings. Due to its complex mix of properties, no single coating will replace hexavalent chromium in all applications. In this presentation, the exploration of the potential of nanostructured coating elaborated with innovative processes, will be discuss as an efficient alternative solution for hard chromium coating replacement. The opportunity to use architecture coating will be presented. Various families of materials will illustrate the correlation between process-Nano structuration and final properties.