热处理对NiTi自膨式血管支架形状恢复能力的影响

Effects of Heat Treatment Conditions on Shape Memory Recovery of NiTi Self-expanding Vascular Stents

摘要: 依据NiTi自膨式血管支架的工作机理及临床使用条件，研究不同热处理条件（包括温度和时间）后的NiTi自膨式血管支架在形状恢复能力的变化及耐腐蚀性能。分析不同热处理工艺条件下支架A_f温度、弹性变形适应性、径向支撑力、局部抗挤压和耐腐蚀等性能指标的变化。结果表明：在热处理温度为500℃，热处理时间为10 min的试验条件下得到的NiTi自膨式血管支架的形状恢复能力为最佳状态，耐腐蚀性满足要求。

Abstract: Effects of heat treatment conditions (including temperature and time) on the shape memory recovery and corrosion resistance of NiTi self-expanding vascular stents were studied based on working mechanism and clinical use. The A_f temperature, dimensional recovery, crush resistance with radially applied load and point applied load of stents and corrosion resistance were characterized in diffident heat treatment conditions. The research results allow the conclusion that the stent treated at 500 ℃ for 10 min has optimum performance, and corrosion resistance meets the requirements.