A finite element methodology for wear–fatigue analysis for modular hip implants

Fretting of the stem-head joint in a prosthetic hip implant is investigated experimentally and computationally. An FE-based methodology for fretting wear-fatigue prediction in a prosthetic hip implant is developed. Tribological and profilometry tests are performed for two head/stem material combinations: Co–28Cr–6Mo/DMLS Ti–6Al–4V and Co–28Cr–6Mo/forged Ti–6Al–4V. The hardness and wear resistance of DMLS Ti–6Al–4V are shown to be superior to those of forged Ti–6Al–4V. The significance of wear in a hip joint for 10 years of service in a normal weight person for moderately intense exercise is predicted for both material combinations. Both material combination joints are shown to have excellent wear resistance which suggests that the wear debris emission will not be significant.