Evaluation of material properties and design requirements for biodegradable magnesium stents
Evaluation of material properties and design requirements for biodegradable magnesium stents
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DOI：
10.1590/s1517-70762010000200002
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发表时间：
2010
影响因子：
0.4
通讯作者：
Stefano FarèI;Qiang GeI;Maurizio VedaniI;Gianmarco VimercatiI;Dario GastaldiII;Francesco MigliavaccaII;Lorenza PetriniII;Stefano TrasattiIII
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文献类型：
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作者：
Stefano FarèI;Qiang GeI;Maurizio VedaniI;Gianmarco VimercatiI;Dario GastaldiII;Francesco MigliavaccaII;Lorenza PetriniII;Stefano TrasattiIII
镁对于生物可降解支架来说是一种非常有吸引力的材料，因为它通过腐蚀过程自然逐渐溶解到人体中，可以防止再狭窄风险，并允许在使用几个月后将机械负荷逐渐传递到周围组织。目前工作的目的是开发关于几种市售镁合金的机械和微观结构数据框架，以考虑它们在可生物降解支架中的用途。因此，对挤压棒材形式的 AZ31、AZ61、AZ80、ZM21、ZK61 和 WE43 合金进行了研究，以比较它们的机械性能和耐腐蚀性能。通过高温压缩测试（温度范围：260-450°C，应变率范围：5•10-4 ÷ 3•10-2 s-1）进行了进一步的高温表征，以评估热挤压制造支架前体（直径1÷2 mm的小管）的最佳加工窗口。本研究提供的实验结果用于支持有限元 (FE) 框架的开发，该框架结合了形状优化程序和镁合金机械和腐蚀损伤行为的详细模型。
Magnesium represents a very attractive material for biodegradable stents since the process of its natural and gradual dissolution into the human body by a corrosion process would prevent restenosis risks and would allow the progressive transmission of the mechanical load to the surrounding tissues after several months of service. The objective of the present work is to develop a frame of mechanical and microstructural data about several commercially available Mg alloys in view of their use for biodegradable stents. The AZ31, AZ61, AZ80, ZM21, ZK61 and WE43 alloys in the form of extruded bars were thus investigated to compare their mechanical properties and corrosion resistance. Further high-temperature characterization was carried out by compression tests at high temperature (temperature range: 260-450°C, strain rate range: 5•10-4 ÷ 3•10-2 s-1) in order to assess the optimal processing window for stent precursors manufacturing (small tubes 1÷2 mm in diameter) by hot extrusion. The experimental results made available by this investigation were adopted to support the development of a finite element (FE) framework combining a shape optimization procedure and a detailed model for Mg alloy mechanical and corrosion damage behavior.