Mechanical and Material Properties of Nitinol and its Application to Stents

Abstract

Nitinol is a functional material with superelastic and shape memory properties derived from its unique molecular structure. The purpose of this thesis is to explore how the material and mechanical properties of self-expanding Nitinol stents affects the forces applied to arterial walls during stent deployment compared to the traditional balloon-expanding stainless steel stents, in addition to contrasting thin and thick-walled pressure vessel mathematical models. Nitinol’s mechanical properties can be optimized for stent applications by tailoring its processing procedures. Nitinol stents demonstrated a reduced circumferential hoop stress on the vessel wall and greater factor of safety with respect to vessel rupture compared to the stainless steel balloon-expanding stents. Nitinol’s unique properties and biocompatibility has led to Nitinol being increasingly utilized for stent applications.