Investigation of Displacements Fields Due to Normal and Tangential Loads on Bars of Finite Thickness

The challenging topic of a cylinder in line contact with bars of finite thickness, reproducing typical fretting fatigue experiments, is studied by means of the super moiré interferometry technique. The authors consider a normal load on a model producing a contact area of about 4 mm, and subsequently on a tangential load at nearly the sliding limit. The displacement fields, due to the normal load, show that the maximum principal stresses at the edge of the contact area are significantly different from those predicted for the half plane, as well as for bars with a significant thickness, so that the dimension of the contact area and the pressure distribution are nearly the same as those of the half plane. This is confirmed by numerical results obtained by Fellows et al. [7]. Moreover, the experimental results show that the surface stresses induced are not as dependent on the thickness of the bar as those induced by the normal load.