Finite element analysis and topology optimization of Ti-6Al-4V hip implant fabricated by laser powder bed fusion process

Abstract

In this work, a three-dimensional thermomechanical finite element model has been developed to simulate the additive manufacturing process of a Ti-6Al-4V hip implant fabricated using the laser powder bed fusion process. The developed numerical model is used to predict the thermal fields, residual stresses, and part deformation during the printing process. To reduce the mass and consequently the weight of the hip implant, topology optimization has been carried out. Furthermore, the additively manufactured Ti-6Al-4V hip implant subjected to realistic loading conditions is analyzed. In the numerical model, new elements are activated for each layer to simulate the recoating of metal powder, and the thermal gradient, residual stress, and deformation associated with the layer are computed. It is observed that the implant geometry significantly influences the quality of the printed part. Topology-optimized geometry shows a notable reduction in residual stress generation and distortions, along with a significant reduction in mass.