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

• Applicant: Professor Dr.-Ing. Philipp Junker
• Subject Area: Computer-Aided Design of Materials and Simulation of Materials Behaviour from Atomic to Microscopic Scale ; Mechanics
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 449916462

The second funding period focuses on developing a numerical model that takes fatigue, corrosion, and bone growth into account when describing the mechanical-chemical deterioration of bioresorbable magnesium implants. By combining the diffusion processes of magnesium resorption, mechanical loads, and biological adaptation of the surrounding bone, the multiphysics model expands on the current numerical methods. An expanded diffusion equation and a damage variable that takes into consideration the material strength loss as a result of mechanical loading and corrosion as a function of load cycles are used to model degradation. By substituting a temporal approach for the conventional geometric multiscale technique, the modeling process is optimized. As a result, expensive computing durations are decreased, and a few computational steps are needed to analyze the material properties' temporal evolution effectively. A connected material description of the implant-bone interaction enables a realistic modeling of the mechanical interaction during implant resorption. To guarantee an effective resolution of the high-dimensional system of partial differential equations, the Neighbor Element Method (NEM) is used for the numerical solution. Validation is done using corrosion and fatigue data from experiments.

• DFG Programme: Research Units
• Subproject of: FOR 5250: Mechanism-based characterization and modeling of permanent and bioresorbable implants with tailored functionality based on innovative in vivo, in vitro and in silico methods