The NextETRUCK partner and pilot leader Ford Otosan presented their research paper on aluminium and steel joints during the European Technical Coatings Congress, which took place on 23-25 September 2024 in the French city of Avignon.
The paper highlighted different way to protect aluminum and steel joints used in vehicles from corrosion, especially when these materials are combined. It focuses on different protective coatings: no coating, a single-layer CrN coating, and a more advanced multilayer coating called CrN/ZrCrN/ZrN, applied using a method called Physical Vapor Deposition (PVD).
Aluminum and steel are lightweight and strong, making them great for cars, but they can corrode when exposed to harsh conditions. The researchers tested a process called electrocoating, where a protective epoxy resin layer is applied to aluminum and steel after pre-treatment with a zinc-phosphate layer. They also applied the PVD coatings to stainless steel bolts used to connect the materials.
The materials were exposed to simulated weather conditions for six weeks to see how well the coatings worked. The multilayer PVD coating performed best, offering the strongest resistance to corrosion. Electrocoating on aluminum was thinner than on steel but still effective.
The study found that using advanced coatings like multilayer CrN/ZrCrN/ZrN significantly reduced corrosion and improved durability, making them ideal for automotive applications where lightweight and long-lasting materials are essential.