Multiscale Analysis of Bulk Metallic Glasses for Cardiovascular Applications

Abstract

Bulk Metallic Glasses, an important class of amorphous metals with no long-range structural disorder, appear to have a futuristic potential for a wide range of applications. Some of the significant properties which bulk metallic glasses possess include optimistic Young’s modulus, good fatigue endurance, higher strength, non-toxicity, improved wear resistance, and excellent corrosion resistance. Most vital property of Bulk Metallic Glasses is that it eliminates surface defects like cracks and crystalline defects like dislocations. These reasons have led to extensive research interest on bulk metallic glasses for biomedical applications such as implant materials. Research till date has a minimal contribution towards the development of Bulk Metallic Glasses as characteristic materials for biomedical applications. In this work, Cu-based bulk metallic glass with a compositional variation of Zr, Al and Ag alloying system is modelled using multiscale methods for cardiovascular stents. Analysis of the simulation results obtained using LAMMPS software, for various compositions of Bulk Metallic Glasses indicates an incremental change in Young’s modulus, ultimate tensile strength, and fracture mechanism is by void formation. The variable strain rates have a considerable effect on the mechanical properties as well as failure mechanics. It is evident that the soft spots due to local structural variations tend to act as initiating points for fracture. The mechanical properties of Bulk Metallic Glasses obtained by Multiscale Modelling are in conformance with the requirements of cardiovascular stents, sufficing that the present compositions of Cu–Zr/Ag/Al can be considered as apt materials.