压握过程中支架发生塑性变形及加工硬化现象将对支架的后续变形行为产生影响.研究利用有限元方法模拟了支架的完整变形过程,评价了扩张后支架的各项性能,并与未考虑压握过程的模拟结果进行了比较.结果表明,压握过程不仅会导致扩张后支架的形状发生变化,同时会使回弹率和最大应力增大,支架最大可扩张直径变小.
Plastic deformation and work hardening may occur in crimping, which can result in changes of material properties and affect the performance of stents. A complete deformation procedure of a typical stent was simulated using finite element method. Its mechanical performances were evaluated and com- pared with that using a simplified procedure (omitting the process of stent crimping). It was found that the crimping has a significant influence on the stent shape, stress distribution, recoil rate and the maximum expandable diameter of stent.