The Rotapower’s rotor housing (trochoid) is aluminum. Is the trochoid’s interior surface coated?
Yes, the production version of the engine is plasma spray coated with a chromium carbide. We have also looked at new types of coatings, including an aluminum oxide “ceramic” type finish. The aluminum oxide is a proprietary formula and deposited by electrochemical process. This oxide surface has a friction coefficient approximately 1/3 of chromium carbide.