Abstract
Wear debris of UHMWPE acetabular cup is a major obstacle limiting the longevity of implanted artificial hip joint. The wear behavior depends on the cyclic stress occurring on the inner spherical surface and its neighborhood. In this study, viscoelastic stress and creep deformation in a hemispherical acetabular cup made of UHMWPE subjected to an axisymmetric loading are analyzed based on the correspondence principle between the Laplace transformed viscoelastic solution and the elastic solution. The inverse of the Laplace transformed viscoelastic solution is carried out by Hosono's method. The effect of the creep deformation on the difference of the head radius and the cup inner radius and the contact area strongly connected with the stress distribution on the inner spherical surface is quantitatively discussed.
