Effects of contact surface shapes on isothermal rolling traction of skewed disks

This paper deals with the effects of contact surface shape on the isothermal rolling traction of skewed disks. The pressure distribution for determining the contact surface shape under dry conditions and the isothermal rolling traction under oil lubrication were calculated by using the software TED/CPA. The findings suggest that at low load, the contact surface shape adopts a closed elliptical shape while at high load, it takes on a truncated elliptical or a rectangular shape. This truncation phenomenon is observed. The isothermal rolling traction calculated using published expressions for point contact differs from that calculated by TED/CPA for the closed elliptical case. By curve-fitting the isothermal rolling traction calculated by TED/CPA for the closed elliptical case, an isothermal rolling traction expression for point contact was modified. As a result, the isothermal rolling traction, in the case where the contact surface shape changes from a closed ellipse to a truncated shape with increasing load, can be estimated using both the proposed expression for point contact and Ohta and Matsuyama's expression for line contact.