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

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.