Comparison of Wear Behaviour of Silicon Nitride and Cast Iron in Lubricated Conditions

In order to assess the capability of ceramics parts to replace metals ones as wear-resistant components in fuel engine, a comparison of wear properties is essential. Using pin-on-disc system, the wear behaviour of several hot presses silicon nitride and cast iron discs against cast iron pins in lubricated conditions was evaluated. All the tests were carried out with the same applied weight and for the same sliding distance. For each coupling, four different sliding speed were used. Foe each test , oil temperature and friction coefficient were continuously registered, while wear amount was estimated by the final weight loss. Scanning electron microscopy was used to individuate wear features. It resulted that when the cast iron pin was coupled with ceramic disk, its wear was much higher than self-matched.