Wear-contact analysis of hip implant coated with functionally graded material
Vinod Pallapu, J. Venumurali
In this paper the wear of acetabular cup in Metal-on-Metal implant is estimated and a means of reducing the wear by using functionally graded materials is addressed. The contact pressure is obtained through finite element tool (Ansys) and the wear is obtained by Archard equation from the contact pressures obtained by Ansys. The contact pressures and wear is estimated for both Metal-on-Metal hip implant as well as implant coated with functionally graded material and the results are compared. The contact pressures are obtained for various loads and orientation of femoral head and acetabular cup according to a 3 dimensional gait cycle. The gait pattern associated with normal walking of human at 4 km/hr is considered for analysis. It was found that the maximum hip load in the gait cycle was about 230% of the body weight of the patient. This gait cycle is divided into 8 instances .It is shown in this work that the linear wear for functionally graded implants are far lesser than Metal-on-Metal implants commercially used today.