Effects of annealing temperature on mechanical properties and corrosion behaviors of biodegradable Mg-3Zn-0.2Ca-2Ag alloy wires
(1. State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China;
2. Center of Digital Dentistry, School and Hospital of Stomatology, Peking University, Beijing 100081, China;
3. Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100144, China)
2. Center of Digital Dentistry, School and Hospital of Stomatology, Peking University, Beijing 100081, China;
3. Plastic Surgery Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing 100144, China)
Abstract: In response to the interest in degradable magnesium staples for oral and maxillofacial surgical procedures, high-performance Mg-3Zn-0.2Ca-2Ag alloy wires were reported. The impact of annealing temperature on the mechanical properties and corrosion behavior of the alloy wires was investigated. Results indicated that an increased annealing temperature led to grain growth, reduced the volume fraction of the second phase, and lowered dislocation density, causing decreased strength. The alloy annealed at 150 °C exhibited the highest elongation (19.6%) due to uniform and fine grains, along with lower dislocation density. Microscopic observation, and electrochemical and immersion tests highlighted the significant influence of annealing temperature on corrosion rates. Alloy wires annealed at 150 °C demonstrated superior corrosion resistance, which is attributed to small and uniform grains, low stress, and a well-distributed nano-second phase. Finally, the alloy wires annealed at 150 °C exhibited enhanced comprehensive properties, making them good candidates for degradable staples.
Key words: biodegradable Mg alloy; magnesium staples; mechanical properties; micro-galvanic corrosion; biocompatibility