Effect of the end-face corner radius of a rubber block on the friction coefficient and fluid-free gap under glycerin lubrication

Abstract

The friction and area of the fluid-free gap between a glass plate and rubber blocks with different end-face corner radii were investigated under glycerin lubrication. Decreasing the end-face corner radius increased both the friction coefficient and area of the fluid-free gap, which indicates that the area and friction coefficient have a positive correlation. The fluid-free gap may be caused by negative fluid pressure associated with rubber block deformation, which increases the contact pressure on the front side of the rubber block. Our findings may contribute to the development of rubber products such as shoe outsoles that provide high friction under lubrication.