Microstructural Evolution and Crystallization Behavior of Amorphous Medium-Entropy Ti-Nb-Zr-Ag Thin Films

Anna Benediktová; Lucie Nedvědová; Michal Procházka; Zdeněk Jansa; Štěpánka Jansová; Christopher D. Woodgate; David Redka; Julie B. Staunton; Ján Minár

arXiv · 2602.20129

Microstructural Evolution and Crystallization Behavior of Amorphous Medium-Entropy Ti-Nb-Zr-Ag Thin Films

Anna Benediktová·Lucie Nedvědová·Michal Procházka·Zdeněk Jansa·Štěpánka Jansová·Christopher D. Woodgate·David Redka·Julie B. Staunton·Ján Minár

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Abstract

Improving the performance of metallic implants increasingly relies on the development of multifunctional surface modifications that combine structural stability, bioactivity, and prevention of bacterial colonization. Medium-entropy alloys (MEAs) represent a promising approach for such coatings, as their chemical complexity allows the formation of structurally stable matrices with tunable properties. In this study, Ti-Nb-Zr and Ti-Nb-Zr-Ag thin films were deposited by magnetron sputtering and subjected to annealing at temperatures of up to 1100 $^{\circ}$C to evaluate the influence of Ag, added for its antibacterial potential, on structural evolution. The as-deposited Ag-free film was fully amorphous, whereas the Ag-containing film exhibited a predominantly amorphous matrix with finely dispersed crystalline nanoparticles, indicating that Ag promoted early-stage crystallization. Both films displayed a fine columnar morphology (column diameter $\sim$15 nm) with dome-like protrusions, a hierarchical surface structure favorable for protein adhesion. Upon annealing, the Ag-free film recrystallized into a granular, loosely packed morphology, while the Ag-containing film retained a compact structure, demonstrating the stabilizing role of Ag. These findings underscore the potential of Ag-containing amorphous MEAs for forming multifunctional coatings with enhanced thermal stability, antibacterial functionality, and biointerface-relevant surface features for advanced biomedical applications.

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Anna Benediktová, Lucie Nedvědová, Michal Procházka, Zdeněk Jansa, Štěpánka Jansová, Christopher D. Woodgate, David Redka, Julie B. Staunton, Ján Minár. 2026-02-23. Microstructural Evolution and Crystallization Behavior of Amorphous Medium-Entropy Ti-Nb-Zr-Ag Thin Films. https://arxiv.org/abs/2602.20129

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