The mechanics of cardiovascular stents during theprocess of expansion are very important for stent function andsafety. In general, finite element method (FEM) or experimentsare major methods used to ascertain mechanical propertiesof the stent. In this paper, we develop a theoreticalmodel of the tubular stent, derive formulas for the axialforces and moments on the stent end, and propose formulasfor the plastic limit pressure vs. the stent's radius duringexpansion. Examples covering different geometrical parametersand material parameters are provided, and the plasticlimit pressures calculated by FEM and the present method arecompared, proving that the present formulas are acceptableand meaningful for the design and innovation of the stent.
