The Oxidation Effect on the Exhaust Valve Seat Wear

Effects of the copper infiltration and the oxide formation on the wear behavior of the sintered exhaust valve seat material were investigated by the pin - on - disc wear test. By the copper infiltration, the wear properties were remakably improved, on the contrast, the oxide deteriorated the wear resistance. The friction coefficient and specific wear rate decreased with the applied load. The dominant wear mechanism was suggested as follows; the spalling of the bulk debris in the non-infiltrated sample and the mild oxidational wear in the infiltrated.