Investigation of effects of surface roughness on the performance of cam mechanisms

The surface roughness of two contacting surfaces significantly influences the tribological performance of the mechanical elements. Their impression is more pronounced under the mixed elasto-hydrodynamic lubrication condition. The cam and flat follower mechanism is a typical sample in which adverse tribological conditions, including direct boundary interactions occurs. In this study, effects of surface roughness on the friction force and friction coefficient are investigated using engine oil at different test conditions in a cam follower mechanism. It is seen that decreasing roughness of the contact surfaces has a more desirable tribological performance, and decrease friction coefficient, therefore increase wear resistance.

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