Manufacturing of Ceramic Valve Discs and their Use in a Rotor CAM Engine

Valve discs of Si3N4 to be used as a vital part in a recently developed rotor cam engine have been manufactured. Si3N4 ceramic has been selected because of its combination of high thermal shock resistance, high wear resistance, low friction coefficient and dimensional stability — all these properties being essential to the optimal running function of the engine. The discs have been produced by the NPS (Nitrided Pressureless Sintering)technique. Design, material selection, processing procedure, engine test results as well as further design and processing development will be discussed. The rotor cam engine with the ceramic valve disc assembled has been successfully test run for more than 80 hours.