In recent years, zinc based alloys as a new biodegradable metal material aroused intensive interests.However, the processing of Zn alloys micro-tubes(named slender-diameter and thin-walled tubes) is very difficult due to their HCP crystal structure and unfavorable mechanical properties. This study aimed to develop a novel technique to produce micro-tube of Zn alloy with good performance for biodegradable vascular stent application. In the present work, a processing method that combined drilling, cold rolling and optimized drawing was proposed to produce the novel Zn–5Mg–1Fe(wt%) alloy microtubes. The micro-tube with outer diameter of 2.5 mm and thickness of 130 μm was fabricated by this method and its dimension errors are within 10 μm. The micro-tube exhibits a fine and homogeneous microstructure, and the ultimate tensile strength and ductility are more than 220 MPa and 20% respectively. In addition, the micro-tube and stents of Zn alloy exhibit superior in vitro corrosion and expansion performance. It could be concluded that the novel Zn alloy micro-tube fabricated by above method might be a promising candidate material for biodegradable stent.
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