Effects of annealing on mechanical properties and degradation behavior of biodegradable JDBM magnesium alloy wires
(1. National Engineering Research Center of Light Alloy Net Forming and State Key Laboratory of Metal Matrix Composite, Shanghai Jiao Tong University, Shanghai 200240, China;
2. National & Local Joint Engineering Research Center of Orthopedic Biomaterials, Department of Bone & Joint Surgery, Peking University Shenzhen Hospital, Shenzhen 518036, China)
2. National & Local Joint Engineering Research Center of Orthopedic Biomaterials, Department of Bone & Joint Surgery, Peking University Shenzhen Hospital, Shenzhen 518036, China)
Abstract: Mg-Nd-Zn-Zr magnesium alloy (JDBM) has been studied widely as biodegradable medical material. To process high quality JDBM wires, effects of annealing on the mechanical properties and degradation behavior after drawing were studied by microscopic observations, tensile and immersion tests. The as-extruded wires with a diameter of 3 mm could be drawn up to 9 passes without annealing until 125% cumulative drawing deformation. Complete recrystallization occurred after annealing at 325 °C for 30 min, 350 °C for 5 min or 450 °C for 3 min, respectively. Room temperature tensile tests and simulated body fluid immersion tests showed that annealing at slightly elevated temperature for short time could obtain better properties due to the finer grain size and more dispersive distribution of precipitates. For this study, annealing at 350 °C for 5 min is the best parameters which can be utilized to further fabricate fine wires.
Key words: Mg-Nd-Zn-Zr alloy; drawing; annealing; mechanical properties; corrosion rate