Invention: Groundbreaking spray-on ceramic coatings
Materials scientists Nuria Espallargas and Fahmi Mubarok have pioneered a method of applying unmeltable ceramics as a protective coating through thermal spraying. Their world-first achievement opens the door to thinner, lighter and longer lasting industrial coatings.
Silicon carbide (SiC) is a hard lightweight ceramic that is well-suited for industrial coatings as it can withstand extreme conditions. However, conventional methods to create SiC coatings are expensive and limited: the coating is applied onto surfaces in a vacuum chamber, resulting in limitations regarding the size and type of component that can be coated. Additionally, thermal spraying - a technique in which powdered material is heated and sprayed onto a surface - is unsuitable as SiC has no melting point. Nuria Espallargas and Fahmi Mubarok have overcome this seemingly impossible challenge by developing a process that enables unmeltable SiC to be used in thermal spraying.
Espallargas and Mubarok found a way to coat ceramic particles with yttrium aluminium garnet, a crystal-like material that protects the ceramic and acts as a binding agent, allowing the spray to stick to surfaces and form a coating. Using this technique, the material scientists have developed a sprayable ceramic material called ThermaSiC that can prevent wear in industrial products.
In overcoming the impossible, Espallargas and Mubarok attracted attention from the aerospace industry. Seram Coatings, the company they spun out of the Norwegian University of Science and Technology, is collaborating on a European Space Agency project. They are testing ThermaSiC coatings to see how well they resist abrasion from sand on the moon and Mars. Additionally, the coatings are being tested in several applications, including brake disks for trains, brake rotors for high-end bicycles, printing rollers and glass shaping tools. The coatings are light and could, for example, reduce weight and therefore fuel consumption in aviation.
Nuria Espallargas (right) and Fahmi Mubarok
Ground breaking spray-on ceramic coatings