Computational modeling of degradation process of biodegradable magnesium biomaterials

TL;DR

This paper presents a validated 3D computational model for magnesium biodegradation, enabling better control of implant degradation by integrating chemistry, experimental calibration, and validation against corrosion data.

Contribution

A physicochemical model of magnesium biodegradation was developed, calibrated with experimental data, and validated, advancing the computational tools for biodegradable implant design.

Findings

Model predicts pH change with maximum 5% error.

Calibration used Bayesian optimization with hydrogen evolution data.

Model validated for practical corrosion scenarios.

Abstract

Despite the advantages of using biodegradable metals in implant design, their uncontrolled degradation and release remain a challenge in practical applications. A validated computational model of the degradation process can facilitate the tuning of implant biodegradation by changing design properties. In this study, a physicochemical model was developed by deriving a mathematical description of the chemistry of magnesium biodegradation and implementing it in a 3D computational model. The model parameters were calibrated using the experimental data of hydrogen evolution by performing a Bayesian optimization routine. The model was validated by comparing the predicted change of pH in saline and buffered solutions with the experimentally obtained values from corrosion tests, showing maximum 5% of difference, demonstrating the model's validity to be used for practical cases.