محمد عباسلو

A novel re-entrant meta-trichiral auxetic (RMCA) structure was designed by combining re-entrant, trichiral and anti-trichiral unit cells. The in-plane behavior of RMCA structure under tensile loading was investigated through finite element analysis and experimental tests were performed to validate the results of these analyses. The effects of different geometric parameters on the in-plane behavior of RMCA structure, including stress-strain curves and Poisson's ratio, were studied using finite element analysis. 3D printing was used to fabricate experimental samples. The most favorable structure obtained from parametric studies was selected and used for vascular stent design. To design the intended vascular stent, the planar structure was folded into a cylinder shape to make the vascular stent. Finite element analysis was used to eva‎luate the behavior of the vascular stent during the deployment process (angioplasty), its mechanical strength, and the interaction between the vascular stent, artery, and plaque. Due to the axisymmetric conditions, only half of the vascular stent, artery, and plaque were modeled for finite element analysis. Important mechanical parameters of vascular stents including elastic recoil, dogboning, and foreshortening were eva‎luated using the results of the finite element analysis. Also, the bending flexibility of the vascular stent was investigated using the experimental three-point bending tests and finite element analysis. To perform the three-point bending test, a vascular stent was fabricated several times larger than the actual size using a 3D printer. In summary, the results showed that the proposed RMCA structure is suitable for cardiovascular applications as a stent due to its excellent auxetic behavior and very low amounts of dogboning, elastic recoil, and foreshortening.

نسبت پوآسون منفي , ساختار آگزتيك , استنت عروقي , تحليل المان محدود , فرآيند آنژيوپلاستي , خمش سه نقطه اي

Negative Poisson's ratio , Auxetic structure , Vascular stent , Finite element analysis , Angioplasty process , Three-point bending

Mohammad Abbaslou

Dr. Ramin Hashemi