Effect of plastic deformation of bulk material on frictional shear stress

Abstract

The frictional shear stress is determined by the real area of contact and the shear strength of the bond in that region. Therefore, a number of studies on the real area of contact have been carried out by using surface asperity models. FEM simulation is carried out to investigate the effects of the plastic deformation of the bulk material on frictional shear stress. The frictional shear stress is proportional to the contact pressure when the plastic deformation of the bulk material is localized at the surface asperity zone. The frictional shear stress turns to increase rapidly with an increase of contact pressure when the whole bulk material begins to deform plastically. Furthermore, the critical value of the contact pressure where the frictional shear stress turns to increase rapidly is controlled by the stress state of bulk material and the friction condition at the real area of contact.