Wear prediction of hard carbon coated hard-on-hard hip implants using finite element method

Abstract

This paper presents finite element (FE) analysis of the effects of hard carbon coatings on wear evolution of hard-on-hard hip implants. Three different types of thin film hard carbon coatings on the articulating surfaces of the bearing components (e.g., on both head and cup) are considered and they are nanocrystalline diamond (NCD), diamond-like carbon (DLC) and polycrystalline diamond (PCD). By considering the 3D angular rotation as well as gait loading for a normal walking cycle, linear and volumetric wears are computed for 20 million cycles. The FE wear model results were validated with experimental hip simulator study available in the literature. FE simulation results showed that as wear progresses, contact stress at the interface between the head and cup decreases with the increase of gait cycles. Wear modelling indicated that PCD coated bearing couple had the least wear evolution as compared to NCD and DLC coated couples.