In-silico design of implants based on a multi-scale approach

In the second funding period, the focus is on the simulation-based development of bioresorbable implants, with particular emphasis on magnesium-based systems. The objective is to realistically capture the interaction between mechanical loading, material degradation, and the biological adaptation of the surrounding bone tissue, and to use this understanding to derive improved implant designs. To this end, a numerical multiphase model is developed in SP-7 that consistently accounts for fatigue, diffusion, corrosion, as well as bone growth and remodeling, enabling the prediction of long-term stability during the resorption process. The framework is designed to describe the coupled evolution of mechanical and biological processes and their influence on structural integrity over extended service periods. For the efficient simulation of high cycle numbers, a time-based multiscale approach at the macroscale is pursued, in which the evolution of the relevant processes is modeled as a function of the number of load cycles. This formulation allows degradation and damage processes to be analyzed over long time spans while avoiding the high computational cost typically associated with conventional approaches. The model parameters are calibrated and validated using experimental data to ensure a realistic representation of implant behavior under cyclic loading. Based on the validated model, in-silico S-N curves and long-term predictions for different loading and environmental conditions are generated.Finally, the developed methods are transferred into application-oriented simulation tools and closely linked with the experimental subprojects within FOR 5250. This integrated workflow enables an iterative exchange between simulation and experiment and supports the targeted optimization of material properties, structural design, and overall implant performance.