Nobuo Sakate

Applications of Ceramics for the Rotary Engine

To meet ever-stringent requirements for higher power and lower lubrication oil consumption on rotary engines, the wear resistance of apex seals and housing surfaces is a critical subject. The authors have been attempting to apply ceramic-based materials to these parts. Through the study on the material composition and production processes, the authors developed a ceramic material with high strength, high toughness and high wear resistance for the apex seals, which is silicon carbide whisker reinforced silicon nitride. As a result of the rig tests, the detonation gun spray of Cr3C2/Ni-Cr was found appropriate for the coating of side housings. In consideration of its potential productivity, the spray method was changed to the plasma spray method. The plasma sprayed Cr3C2/Ni-Cr showed the wear resistance equivalent to that of the detonation gun sprayed coating as a result of the optimization of material powder granulation and the spray conditions.