镁合金微细管热挤压-冷拉拔工艺  

Research on hot extrusion and cold drawing for micro-tube of magnesium alloys

作　　者：方刚[1] 闫凯民[1] 曾攀[1] 艾卫江 

机构地区：[1]清华大学机械工程系,北京100084 [2]上海核工程设计研究院,上海200233

出　　处：《塑性工程学报》2013年第5期11-15,共5页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51075230)

摘　　要：镁合金作为可生物降解材料,在医疗植入物中的应用已得到越来越多的关注,例如血管支架。在血管支架的生产中,管坯制备是必不可少的工艺环节。因此,研究和确定一种可靠的规模化生产镁合金微细管的工艺路线十分必要。该文通过对热反挤压-冷拉拔制备镁合金微细管的工艺研究,开发了专用的微细管热挤压机,其具有对挤压力、温度和速度同时测量的功能。通过该专用挤压机,挤压出了外径3.14mm、壁厚0.32mm的ZK30镁合金微细管。在万能材料试验机上设计拉拔实验工装和模具对镁合金管进行室温拉拔。经4道次的拉拔,可得到外径2.90mm、壁厚0.27mm的镁合金微细管,用于后续的精密成形和激光切割中,制备生物实验所需的血管支架。As biodegradable materials, the magnesium alloys get more and more attentions in the application of implants for sur- gery, for example, vascular stents. Forming of tubular billet is an indispensible step in the stent fabrication chain. Therefore, the reliable forming methods have to be researched and determined for the production of the micro tube of magnesium alloy. The present research proposes a serial of processes to form a micro tube of magnesium alloy, including the hot indirect extrusion and the cold drawing. An in-house micro hydraulic press with measurement units of pressure, displacement and temperature was de- veloped to extrude the tube of magnesium alloy. By the indirect extrusion of ZK30 magnesium alloy, some tubular billets with an outer diameter of 3.14mm and a wall thickness of 0.32mm were obtained. Subsequently, the cold drawing was used to further forming to get the thinner tube. The drawing experiments were carried out on the specialized drawing dies and the tool sets mounted a universal material testing machine. Through four passes, some tubes with an outer diameter of 2.90mm and a wall thickness of 0.27mm were formed. The formed tubes will be used to the further precision forming and laser slitting of vascular stents designed to the mechanical and bio tests.

关 键 词：镁合金 管材成形 挤压 拉拔 支架 

分 类 号：TG379[金属学及工艺—金属压力加工] TG359