Large scale atomistic simulation of size effects in micropillars
29 Nov 2016 | Presentations | Contributor(s): Mohammadreza Yaghoobi, George Voyiadjis
The present paper studies the size effects during the micropillar compression test in Ni thin films using large scale atomistic simulation. Different micropillar sizes are simulated to investigate...
Role of grain boundary on the sources of size effects
29 Nov 2016 | Presentations | Contributor(s): George Voyiadjis, Mohammadreza Yaghoobi
The present work investigates the effects of grain boundary (GB) on the sources of size effects. Up to now, several studies have been conducted to address the role of GBs in size effects from the...
Strain gradient plasticity for incremental and non-incremental theories under non-proportional loading
29 Nov 2016 | Presentations | Contributor(s): George Voyiadjis, Yooseob Song
A thermodynamically consistent coupled framework of higher-order strain gradient plasticity theory is developed based on the formulations of the incremental and non-incremental theory respectively...
Effect of Passivation on Higher Order Gradient Plasticity Models for Non-proportional Loading: Energetic and Dissipative Gradient Components
29 Nov 2016 | Publications | Contributor(s): George Voyiadjis, Yooseob Song
In this work, a new class of thermodynamic-based higher order gradient plasticity theory is proposed and applied to the stretch-surface passivation problem for investigating the material behaviour...
Higher Order Thermo-Mechanical Gradient Plasticity Model with Energetic and Dissipative Components
29 Nov 2016 | Publications | Contributor(s): George Voyiadjis, Yooseob Song, Taehyo Park
The thermodynamically consistent framework accounting for the thermo-mechanical behavior of the microstructure is addressed using the finite element implementation. In particular, two different...
Size Effects in FCC Crystals During the High Rate Compression Test
29 Nov 2016 | Publications | Contributor(s): Mohammadreza Yaghoobi, George Voyiadjis
The present work studies the different mechanisms of size effects in fcc metallic samples of confined volumes during high rate compression tests using large scale atomistic simulation. Different...
Ab Initio Density Functional Theory Method Study on the MoNbTaVW Alloy System
23 Nov 2016 | Publications | Contributor(s): Yan Yang, Ebrahim Khosravi, Guoqiang Li, Patrick Mensah, Dwayne Jerro, Samuel Ibekwe, Ghanashyam Joshi, Boliang Zhang, Shengmin Guo, and Shizhong Yang
The high-entropy alloy (HEA) MoNbTaVW system was studied through ab initio density
functional theory (DFT) method and weighted random body centered cubic structure (BCC) models. The bulk...