Development and industrial implementation of a biodegradable surgical wire production technology from ZnMg0.004 alloy: In vitro assessment of degradation rate and mechanical property changes

Abstract. The paper discusses the technology for the production of the new biodegradable surgical wire, developed at AGH, along with the experience of its integration into INTERMECH's production processes. This wire's basic mechanical and corrosion properties are thoroughly examined. The developed technology is based on the use of a combination of hot and cold (in the last passes) drawing of a workpiece obtained by hot extrusion. Hot drawing allows to achieve the necessary ductility of the wire, while the final cold drawing improves the surface quality, which is important in the context of the biological properties of the wire. To assess biodegradation rates, in vitro testing was conducted within a natural corrosive environment (using bovine serum from Biowest). Mechanical tensile tests were performed on wires at various stages of corrosion, ranging from 3 to 30 days, in addition to the original wire. These tests were carried out using a Zwick 250 testing machine. The study revealed that the tensile strength of all produced wires decreases by less than 50% after 30 days of corrosion. Further experimental investigations were conducted to monitor changes in wire mass over time. The tests spanned 120 days, during which the corrosion rate declined from 2 mm/year in the initial days to approximately 0.05 mm/year in the later stages. This study indicates that when planning the use of this wire in bone surgery, a corrosion time of 1-2 years should be anticipated. In cases where the wire is exposed to intense bodily fluid flushing, this timeline may be shorter.