用于主动脉支架的NiTi合金丝材的性能改善

Performance Improvement of the NiTi Alloy Wire Used for Aortic Stent-graft

为了改善主动脉支架的物理性能和生物相容性,对支架制备过程中的NiTi合金丝材热处理和电化学抛光过程进行研究.结果表明,热处理不仅可以有助于支架段的定型,而且可以提高丝材机械性能.热处理温度480℃×7min+510℃×7min时最为理想,可以获得较好的物理性能.电化学抛光可以改善丝材表面质量,显著提高丝材的疲劳寿命,并减少附壁血栓形成和内皮增生.

In order to improve the physical properties and biocompatibility of the aortic stent-graft,the effects of heat treatment and electrochemical polishing on nickel-titanium（NiTi） alloy wire during the stent-graft preparation were studied.It is found that heat treatment could help shaping the stent-graft and enhance the mechanical proper-ties of the NiTi wire.The ideal heat-treatment process is heating at 480℃ and 510℃ for 7 min,respectively.By electrochemical polishing,the surface quality and fatigue life of the wire is highly improved.Meanwhile,electro-chemical polishing results in reduction of the possibility of the mural thrombus formation and endothelial hyperplasy.