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Full-Text Articles in Engineering
Development Of Interatomic Potential Of High Entropy Diborides With Artificial Intelligence Approach To Simulate The Thermo-Mechanical Properties, Nur Aziz Octoviawan
Development Of Interatomic Potential Of High Entropy Diborides With Artificial Intelligence Approach To Simulate The Thermo-Mechanical Properties, Nur Aziz Octoviawan
MSU Graduate Theses
The interatomic potentials designed for binary/high entropy diborides and ultra-high temperature composites (UHTC) have been developed through the implementation of deep neural network (DNN) algorithms. These algorithms employed two different approaches and corresponding codes; 1) strictly local & invariant scalar-based descriptors as implemented in the DEEPMD code and 2) equivariant tensor-based descriptors as included in the ALLEGRO code. The samples for training and validation sets of the forces, energy, and virial data were obtained from the ab-initio molecular dynamics (AIMD) simulations and Density Functional Theory (DFT) calculations, including the simulation data from the ultra-high temperature region (> 2000K). The study …
Machine Learning Strategies For Potential Development In High-Entropy Driven Nickel-Based Superalloys, Marium Mostafiz Mou
Machine Learning Strategies For Potential Development In High-Entropy Driven Nickel-Based Superalloys, Marium Mostafiz Mou
MSU Graduate Theses
In this study, I developed Deep Learning interatomic potentials to model a multi-phase and multi-component system of Ni-based Superalloys. The system has up to three major phase constituents, namely Gamma, Gamma Prime, and Transition-metal rich Carbide. I utilized invariant scalar-based and/or equivariant, tensor-based neural network (NN) approach as implemented in DEEPMD, NEQUIP/ALLEGRO codes, respectively, and Moment Tensor Potential (MTP). For the training and validation sets, I employed the ab-initio molecular dynamics (AIMD) trajectory results and ground state DFT calculations, including the energy, force, and virial database from highly diverse compositions, temperatures, and pressures following a “High Entropy Strategy.” The Deep …
Development Of Eam And Rf-Meam Interatomic Potential For Zirconium Diboride, Bikash Timalsina
Development Of Eam And Rf-Meam Interatomic Potential For Zirconium Diboride, Bikash Timalsina
MSU Graduate Theses
Embedded Atom Method (EAM) and Modified-EAM (MEAM) interatomic potentials were developed for zirconium diboride (ZrB2). The EAM and “Reference Free” (RF) version of the Modified Embedded Atom Method (RFMEAM) potentials have been fitted by utilizing Density Functional Theory (DFT)-based datasets including lattice deformations and high-temperature ab-initio molecular dynamics (AIMD) simulation results. The occupancies of phonons for acoustic phonon modes from the density functional theory calculation shows that these modes of vibration, mostly due to heavier mass element (Zr), which occur below 8.711 THz, while a slight underestimation to that of DFT calculation predicted by EAM below 8.439 THz …
Study Of Amorphous Boron Carbide And Hydrogenated Boron Carbide Materials Using Molecular Dynamics And Hybrid Reverse Monte Carlo, Rajan Khadka
MSU Graduate Theses
We present a computational study of amorphous boron carbide (a-BxC) models using Molecular Dynamics (MD) studied with Stillinger-Weber (SW) and ReaxFF potential. The atomic structure factor (S(Q)), radial distribution function (RDF) and bond lengths comparison with other experimental and ab initio models shows that a random arrangement of icosahedra (B12, B11C) interconnected by chains (CCC, CBC) are present in a-BxC. Afterward, Hybrid Reverse Monte Carlo (HRMC) technique is used to recreate a-BxC structures. The existing SW potential parameters of Boron are optimized for the α-rhombohedral (Icosahedral B12 …
Development Of Multicomponent Eam Potential For Ni-Based Superalloy, Muztoba Rabbani
Development Of Multicomponent Eam Potential For Ni-Based Superalloy, Muztoba Rabbani
MSU Graduate Theses
We initiated the development of multi-component EAM potentials for Aluminides and Carbides, key phases in Ni-based Superalloys. The goal is to utilize the MD simulation to understand the deformation dynamics that contribute to the formation of voids and creep initiation. For this purpose, we constructed the raw data from ab-initio (molecular dynamics) MD simulations fed into the potential development code and used Nickel as the base metal with the addition of a number of various elements including Aluminum, Chromium, Tungsten. We then developed the EAM potentials for the aluminide and carbide phases using the force-fitting code MEAMfit. Our generated potential …
Molecular Dynamics Study Of Creep Deformation In Nickel-Based Superalloy, Sabila Kader Pinky
Molecular Dynamics Study Of Creep Deformation In Nickel-Based Superalloy, Sabila Kader Pinky
MSU Graduate Theses
The present study employs molecular dynamics simulations of Ni-based superalloy to investigate the creep behavior under uniaxial compression test. Dislocation dynamics is analyzed for the nickel-based single crystal superalloy with the presence of void and with varying the distribution of gamma-prime phase The results show that multiple-void systems are more prone to yield than single-void systems and single-void systems are more prone to yield than the system without void. From the simulations, it has been determined that the creep mechanism in Ni/Ni3Al is subject to change on the applied stress depending on the distribution of gamma-prime phases change. Dislocation behavior …
Study Of Iron Ion Transit Through Three-Fold Channel Of Ferritin Cage, Shah Alam Limon
Study Of Iron Ion Transit Through Three-Fold Channel Of Ferritin Cage, Shah Alam Limon
MSU Graduate Theses
Ferritin is an iron-storage globular protein with an ability to uptake, mineralize and release iron ions in a controllable manner. The globular hollow shell allows storage of mineralized iron, with several channels responsible for the transit of ions into the shell and out of it. Understanding of the detailed molecular functioning of ferritin is required for rational design of biomimetic conjugate nano-biosystems containing ferritin-like constituents. In this work, ferritin was investigated both numerically by all-atom molecular dynamics (MD) simulations, and experimentally by Raman spectroscopy. Molecular dynamic simulations of a model system comprising iron ions (Fe2+) and a ferritin trimer expressing …
Development Of Many-Body Potential For Deformation Study In Al-Tin Nanolayered Composites, Paul Yaohan Simanjuntak
Development Of Many-Body Potential For Deformation Study In Al-Tin Nanolayered Composites, Paul Yaohan Simanjuntak
MSU Graduate Theses
A novel interatomic potential of ternary Al-Ti-N has been developed to study the deformation behavior of Al-TiN nanolaminates. The ternary nanolayered Al-TiN composite has attracted a lot of interest due to its combination of strength and ductility. The current analysis on the system has been primarily concentrated on continuum models which are inadequate to explain the key deformation events such as nucleation and interaction of dislocations. Progress in the preferred atomistic approach has been hampered however by the lack of available interatomic potential optimized for the ternary system. I developed a many-body potential based on embedded atomic model (EAM) by …
An Experimental And Computational Investigation Of The Mechanical, Structural, And Hydrothermal Properties Of Mesoporous Materials, Dayton Gage Kizzire
An Experimental And Computational Investigation Of The Mechanical, Structural, And Hydrothermal Properties Of Mesoporous Materials, Dayton Gage Kizzire
MSU Graduate Theses
Periodic mesoporous materials have tunable pore sizes and high surface to volume ratios. Some of the most anticipated applications are those that call for energy harvesting in extreme environments, and these materials have a great structural stability to withstand the harsh conditions. In this work, the structural properties of mesoporous materials SBA-15 silica and Al-SBA-15 aluminosilica have been investigated by pressure dependent in situ small angle x-ray scattering (SAXS) using a diamond anvil cell (DAC) up to ~12 GPa in pressure. Hydrothermal measurements were also made in this manner to near supercritical water/steam conditions (to 255 °C and ~ 114 …