The processing of Mg-Zn-Y-Nd alloy micro-tubes and vascular stent

• 1、School of Materials Science and Engineering, Zhengzhou University, 450001

Abstract：Magnesium alloy is considered to be one of the most promising stentmaterials because of its good biocompatibility and degradability. However, the poor plasticity of magnesium alloy at room temperature is one of the key factors that restricting the preparation of micro-tubes and the research about laser cutting is relatively small.In this paper, tube blank with diameter of 3.2mm and wall thickness of 0.4mm was obtained by hot extrusion, then micro-tubes with diameter of2.0mm, wall thickness of 0.15mm and length of 80mm was fabricated by long mandrel drawing andthe intermediate annealing process. Tensile test resThe processing of Mg-Zn-Y-Nd alloy micro-tubes and vascular stentults show that the strength and elongation of micro-tubesafter annealing reach 298MP and 20%, respectively.It's appropriate to select 80-85W as the peak power during the cutting processing and use a large cutting speed to ensure the surface quality of the strut near, at the same time, the matrix microstructure near incision has not changed. Phosphoric acid as a main component is more suitable for electrolytic polishing of Mg-Zn-Y-Nd alloy stent. After electrolytic polishing, the stents' surface quality is better and looks bright, there is no over-etching. The successful preparation of micro-tubes and its vascular stents has accelerated the clinical application of magnesium alloys in cardiovascular disease.

Keywords： Mg-Zn-Y-Nd alloy micro-tubes vascular stents laser cutting electrolytic polishing