EFFECTS OF TEXTURING ON STRESS DISTRIBUTION OF A UHMWPE SURFACE

The effect of texturing cavities on the stress distribution of an UHMWPE surface was studied using the finite element method on a nonconforming contact between a steel ball and a flat UHMWPE textured surface. Two and threedimensional analyses were conducted for different texture patterns taking into account the non-linear behavior of the stress-strain curve of the polymer. The numerical analysis was purely static using a normal load of 17 N for the analyses. The simulation shows a deleterious effect in von Mises stress and contact pressure on a textured surface, due to the reduction of the effective contact area. Filling the texture cavities with an incompressible liquid reduces the stress level and contact pressure, enlarging the contact area. From the simulation both diameter and distribution of cavities that hinder stress concentration with a maximum design stress of 13.5 MPa were determined.