Research on the Elastic and Plastic Deformation of CoCr Alloy Used for Coronary Stents

Abstract

The Percutaneous Transluminal Coronary Angioplasty (PTCA) assisted with stenting has become one of the effective means to cure heart disease. In practice, when the balloon and stent are assembled and the stent expands after being inputted, the stent will be compressed and stretched with elastic and plastic deformation twice, which affects the limit load and fatigue strength. In order to grasp the elastic or plastic deformation of CoCr alloy used for coronary stents, this paper proposed solutions based on compression and expansion experiments and analyzed the effect that pre-deformation does on material’s property, since stents were compressed before being stretched. The results suggested that pre-compression plastic deformation have almost no effect on the tensile strength of the material, but the tensile elongation of the material decreased.