Atomistic simulation of Voronoi-based coated nanoporous metals


Yıldız Y. O. , Kırca M.

MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING, cilt.25, 2017 (SCI İndekslerine Giren Dergi) identifier identifier

  • Cilt numarası: 25 Konu: 2
  • Basım Tarihi: 2017
  • Doi Numarası: 10.1088/1361-651x/25/2/025008
  • Dergi Adı: MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING

Özet

In this study, a new method developed for the generation of periodic atomistic models of coated and uncoated nanoporous metals (NPMs) is presented by examining the thermodynamic stability of coated nanoporous structures. The proposed method is mainly based on the Voronoi tessellation technique, which provides the ability to control cross-sectional dimension and slenderness of ligaments as well as the thickness of coating. By the utilization of the method, molecular dynamic (MD) simulations of randomly structured NPMs with coating can be performed efficiently in order to investigate their physical characteristics. In this context, for the purpose of demonstrating the functionality of the method, sample atomistic models of Au/Pt NPMs are generated and the effects of coating and porosity on the thermodynamic stability are investigated by using MD simulations. In addition to that, uniaxial tensile loading simulations are performed via MD technique to validate the nanoporous models by comparing the effective Young's modulus values with the results from literature. Based on the results, while it is demonstrated that coating the nanoporous structures slightly decreases the structural stability causing atomistic configurational changes, it is also shown that the stability of the atomistic models is higher at lower porosities. Furthermore, adaptive common neighbour analysis is also performed to identify the stabilized atomistic structure after the coating process, which provides direct foresights for the mechanical behaviour of coated nanoporous structures.