Feasibility of using bulk metallic glass for self-expandable stent applications

作者：Kumar Gideon Praveen; Jafary Zadeh Mehdi; Tavakoli Rouhollah; Cui Fangsen

来源：Journal of Biomedical Materials Research Part B: Applied Biomaterials , 2017, 105(7): 1874-1882.

DOI：10.1002/jbm.b.33718

• self-expandable stent
• bulk metallic glass
• finite element analysis
• molecular dynamics simulations
• crimping
• nitinol

Self-expandable stents are widely used to restore blood flow in a diseased artery segment by keeping the artery open after angioplasty. Despite the prevalent use of conventional crystalline metallic alloys, for example, nitinol, to construct self-expandable stents, new biomaterials such as bulk metallic glasses (BMGs) are being actively pursued to improve stent performance. Here, we conducted a series of analyses including finite element analysis and molecular dynamics simulations to investigate the feasibility of using a prototypical Zr-based BMG for self-expandable stent applications. We model stent crimping of several designs for different percutaneous applications. Our results indicate that BMG-based stents with diamond-shaped crowns suffer from severe localization of plastic deformation and abrupt failure during crimping. As a possible solution, we further illustrate that such abrupt failure could be avoided in BMG-based stents without diamond shape crowns. This work would open a new horizon for a quest toward exploiting superior mechanical and functional properties of metallic glasses to design future stents.

• 出版日期2017-10