Silver influence of multi-functional Zr-Cu based TFMGs on their antibacterial activity.

G. NKOU BOUALA, A. ETIEMBLE¹, C. DER LOUGHIAN¹, C. LANGLOIS¹, S. CARDINAL¹, J.M. PELLETIER¹, J.F. PIERSON², P. STEYER¹

[1] MATEIS Laboratory-INSA de Lyon, 2 Avenue Jean Capelle, 69621, Villeurbanne cedex, France
[2] Institut Jean Lamour, Université de Lorraine, 54011 Nancy, France

Keywords: Magnetron sputtering, Thin Film Metallic Glasses, Antibacterial activity, microstructure, Physico-chemical properties

"Thin film metallic glasses (TFMG) have recently emerged as alternative materials for many applications (micro-electro-mechanical systems and biomedical use), owing to their unique characteristics such as large elastic limit, high toughness and high corrosion resistance.

These characteristics are related to their microstructure that lacks long-range-order atomic periodicity and amorphous texture. However, if the mechanical properties of the TFMGs have been largely studied, just few studies have been focused on the understanding of their microstructure evolution during heating.

In order to investigate the thermal stability of antibacterial magnetron-sputtered Zr-Cu and Zr-Cu-Ag TFMGs, the present study proposes a multiscale characterization involving in situ techniques. First, the crystallization behavior and structural stability were investigated by in situ high temperature XRD combined to DSC experiments, during a continuous heating from room temperature to 600°C under vacuum. Moreover, due to the fast diffusion of silver, silver-based coatings are subject to dewetting. Such process, leading to the formation of micrometric segregated micrometer-sized domains, was observed in situ by using HT-environmental SEM. Finally, at a deeper nanometric scale, in situ HT-TEM was used to observe, during heating, the progressive formation of crystallized grains from the initial amorphous matrix.

Through such a multiscale in situ approach, we should better understand the general evolution of the TFMGs under thermal constraint."