Abstract
In this study, we clarified the parameters of surface roughness that have a high correlation with the friction coefficient and made clear the factors producing a high friction coefficient by measuring the mechanical characteristics of the boundary lubrication film. We verified that improving the friction coefficient between the belt elements and pulleys of a metal belt CVT by 20% over the current level can improve vehicle fuel economy by 2%. This can be achieved by combining control of the pulley surface properties with a high-friction CVT fluid.
