Loading...
Search for:
nanocrystaline
0.006 seconds
Temperature-dependent Multi Scale Large Deformation Simulation of Heterogeneous Crystals
, M.Sc. Thesis Sharif University of Technology ; Khoei, Amir Reza (Supervisor) ; Jahanshahi, Mohsen (Co-Advisor)
Abstract
In this study, a novel and unprecedented multi-scale hierarchical molecular dynamics (MD) – finite element (FE) coupling method is proposed to demonstrate the influence of temperature on mechanical properties of heterogeneous Nano-crystalline structures. The embedded-atom method (EAM) many-body interatomic potential is implemented to consider pairwise interactions between atoms in the metallic alloys with face-centered-cubic (FCC) lattice structure at different temperatures. In addition, the Nose-Hoover thermostat is employed to adjust the fluctuation of temperature. In order to calculate the equivalent lattice parameter, a weight average between the lattice parameters of atomic structures...
The influence of surface nanocrystallization induced by shot peening on corrosion behavior of niti alloy
, Article Journal of Materials Engineering and Performance ; Volume 24, Issue 8 , August , 2015 , Pages 3093-3099 ; 10599495 (ISSN) ; Sadrnezhaad, S. K ; Atai, M ; Sharif University of Technology
Springer New York LLC
2015
Abstract
Nickel-titanium (NiTi) shape memory alloys have been widely used as implant materials, due to their superior shape memory properties and similar mechanical behavior to bone tissue. The presence of nickel on the surface of nickel-titanium alloy and release of this ion in the body environment will result in some allergic reactions. In current study, we used shot pinning process to produce nanocrystalline nickel-titanium alloy with increased corrosion resistance. Field emission scanning electron microscopy (FE-SEM), x-ray diffraction (XRD) analysis, and atomic force microscopy were employed to investigate the surface features of samples. The quantitative chemical analysis of NiTi and modified...