Ni-free Ti-based bulk metallic glasses (BMGs) are prospective biomaterials for biomedical applications. Compared with conventional Ti alloy, Ni-free Ti-based BMGs have shown exciting properties such as high corrosion resistance, good biocompatibility, high strength, and low Young’s modulus, making them suitable for hard-tissue implants, thanks to their amorphous nature and lack of grain boundaries [1,2]. Furthermore, BMGs can be shaped and patterned by viscous flow deformation using thermoplastic net-shaping (TPN) when heated up to the supercooled liquid region (SCLR) [2,3]. In clinical practices, bacterial adhesion and biofilm formation on implant surfaces are the main risks for implant-associated infections, leading to medical treatment failure [4]. Several bio-inspired nanostructured surfaces have been proven mechano-bactericidal effects [5]. Hence, this work aims to create nano-patterns and hierarchical structures on the Ti₄₀Zr₁₀Cu₃₄Pd₁₄Sn₂ BMG to enhance osseointegration and antibiofilm properties for hard-tissue implant applications. This work reveals a novel strategy for processing Ti₄₀Zr₁₀Cu₃₄Pd₁₄Sn₂ BMG with TPN. Instead of operating for a short time slightly above the glass transition temperature to avoid crystallization, the proposed method accepts the formation of nanocrystals and makes use of the lower viscosity of the supercooled liquid when processing above the glass transition temperature. The results show that if the first crystallization event is the formation of nanocrystals, the BMGs can still be deformed and patterned even with the nanocrystallization [6]. The designed materials are examined with in-vitro studies for biocompatibility and antibacterial performance.  

[1] A. Liens, A. Etiemble, P. Rivory, S. Balvay, J.-M. Pelletier, S. Cardinal, D. Fabrègue, H. Kato, P. Steyer, T. Munhoz, J. Adrien, N. Courtois, D. Hartmann, J. Chevalier, On the Potential of Bulk Metallic Glasses for Dental Implantology: Case Study on Ti₄₀Zr₁₀Cu₃₆Pd₁₄, Materials. 11 (2018) 249. https://doi.org/10.3390/ma11020249.

[2] S. Bera, B. Sarac, S. Balakin, P. Ramasamy, M. Stoica, M. Calin, J. Eckert, Micro-patterning by thermoplastic forming of Ni-free Ti-based bulk metallic glasses, Materials & Design. 120 (2017) 204–211. https://doi.org/10.1016/j.matdes.2017.01.080.

[3] B. Sarac, S. Bera, F. Spieckermann, S. Balakin, M. Stoica, M. Calin, J. Eckert, Micropatterning kinetics of different glass-forming systems investigated by thermoplastic net-shaping, Scripta Materialia. 137 (2017) 127–131. https://doi.org/10.1016/j.scriptamat.2017.02.038.

[4] J.G.S. Souza, M.M. Bertolini, R.C. Costa, B.E. Nagay, A. Dongari-Bagtzoglou, V.A.R. Barão, Targeting implant-associated infections: titanium surface loaded with antimicrobial, IScience. 24 (2021) 102008. https://doi.org/10.1016/j.isci.2020.102008.

[5] D.P. Linklater, V.A. Baulin, S. Juodkazis, R.J. Crawford, P. Stoodley, E.P. Ivanova, Mechano-bactericidal actions of nanostructured surfaces, Nature Reviews Microbiology. 19 (2021) 8–22. https://doi.org/10.1038/s41579-020-0414-z.

[6] F.-F. Cai, B. Sarac, Z. Chen, C. Czibula, F. Spieckermann, J. Eckert, Surmounting the thermal processing limits: Patterning TiZrCuPdSn bulk metallic glass even with nanocrystallization, Materials Today Advances. 16 (2022) 100316. https://doi.org/10.1016/j.mtadv.2022.100316.