INTEGRITY ASSESSMENT OF REVERSE ENGINEERED Ti-6Al-4V ELI TOTAL HIP REPLACEMENT IMPLANT
Tamara Mijatović1, Aleksa Milovanović1, Aleksandar Sedmak2, Ljubica Milović3, Katarina Čolić1
1)University of Belgrade, Innovation Centre of the Faculty of Mechanical Engineering, Belgrade, Serbia
2)University of Belgrade, Faculty of Mechanical Engineering, Belgrade, Serbia
3)University of Belgrade, Faculty of Technology and Metallurgy, Belgrade, Serbia
Total hip replacement implants are used as an artificial replacement for disfunctional hips in order to sustain joint movement. Chosen material and design of total hip replacement are the most influential factors for artificial joint utilization. Selected total hip replacement is obtained by precision casting method, made from Ti6Al4V ELI (Extra Low Interstitials) alloy. In order to acquire a geometrical model of chosen implant, the 3D scanner is used and an obtained point cloud (PC), then exploited for reverse engineering to a CAD model. The neck thickness of implant affects angle of movement of the joint and structural integrity. Reducing the thickness of the neck section results in higher movement of the joint, but inversely affects its structural integrity. The 3D scanned implant has a neck thickness of 14.6 mm, and data from literature suggest that the best movement angle is for 9 mm thickness of the implant. In order to redesign the available implant, five different models with a neck thickness between 9 and 14.6 mm are made. Obtained results show the thickness effects the stress distribution in a critical area.
Keywords: total hip replacement implant, finite element method (FEM), Ti-6Al-4V ELI alloy, reverse engineering, 3D scanner ‘Geomagic Capture’