First-principles calculations of diffusion activation energies for designing anti-self-aging biodegradable zinc alloys

Zn alloys are promising materials for application in the fabrication of vascular stents because they have a desirable degradation rate and acceptable biocompatibility. However, the poor thermostability of Zn is one limitation that needs to be addressed in order to broaden their clinical applications. Suppression atomic diffusion is of practical significance when enhancing the thermostability of Zn alloys. The present study seeks to examine lattice diffusion associated with various alloy elements by calculating the diffusion activation energies for nineteen substitutional solutes via first-principles calculations combined with CINEB methods. The calculated activation energies depend strongly on the size and the number of d-electrons of the solute atoms. The trend to improve the thermostability and creep resistance of Zn alloys at ambient temperature can also be predicted using the Nabarro-Herring model. An anti-self-aging Zn-Cu alloy was prepared to verify our calculation results. Therefore, the present work has great significance for the design of biodegradable zinc alloys with improved thermostability. Graphic abstract