Article
Engineering, Multidisciplinary
Mojtaba Shariati, Babak Azizi, Mohammad Hosseini, Mohammad Shishesaz
Summary: This research focuses on the calibration of small-scale parameters of non-classical continuum theories for circular nanoplates, using various methods and techniques such as GDQR and molecular dynamics simulation. It was found that the nonlocal strain gradient method aligns well with the results of molecular dynamics in predicting natural frequencies, while other methods such as stress-driven nonlocal and strain-driven nonlocal elasticity have discrepancies in their predictions. These findings are valuable for researchers in non-classical continuum mechanics.
INTERNATIONAL JOURNAL OF ENGINEERING SCIENCE
(2021)
Article
Materials Science, Multidisciplinary
Dayton G. Kizzire, Alex D. Greenhalgh, Max L. Neveau, Collin M. Pekol, Michael J. Thompson, Orlando Rios, David J. Keffer
Summary: A Modified Embedded Atom Method (MEAM) potential for γ-Ce has been generated for use in MD simulations, providing accurate estimates of material properties across a broad temperature range.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Engineering, Mechanical
Xiaomo Yu, Allam Maalla, Zohre Moradi
Summary: This study introduces an analytical strategy for investigating the stability and frequency characteristics of nano-sized rectangular plates by modifying the nonlocal couple stress theory, discussing the impact of size-dependent factors on the performance of piezoelectric NEMS. The results show that the length of the nanoplate and l/h factor directly affect the performance of piezoelectric nanoplates, but in some cases, like when the l/h factor is large, frequency performance may not change.
MECHANICAL SYSTEMS AND SIGNAL PROCESSING
(2022)
Article
Chemistry, Physical
Xin Song, Fangjun Shao, Zijiang Zhao, Xiaonian Li, Zhongzhe Wei, Jianguo Wang
Summary: In this study, a single-atom Ni-modified Al2O3-supported Pd catalyst was proposed for the selective semi-hydrogenation of alkynes with high activity at low temperatures and pressures. The catalyst exhibited good stability and achieved efficient reactions at lower temperatures and pressures, benefiting from the synergistic effect of Pd and Ni.
Article
Materials Science, Multidisciplinary
Murray S. Daw, Michael Chandross
Summary: We extend the parametric form of Embedded Atom Method interatomic potentials for FCC metals to treat alloys and study the dependence of alloy properties on model parameters. We introduce the concept of spread alloys, where constituent elements are defined as perturbations from an average FCC metal, and show that the model can describe the clustering and ordering tendencies of metal alloys. We prove a general theorem that alloy properties in random equimolar alloys differ from a simple rule of mixtures only based on the standard deviation among constituent parameters, independent of the number of constituents.
Article
Materials Science, Multidisciplinary
Murray S. Daw, Michael Chandross
Summary: We propose a simple parametric form for interatomic potentials of the Embedded Atom Method (EAM-X) for pure FCC metals and investigate the relationship between basic properties and input parameters. Instead of fitting a set of functions to experimental data or density functional theory calculations, we adopt an inside-out approach to understand how complex properties depend on the EAM-X parameters. This method enables the identification of desired parameter regions and the matching of those parameters to real elements.
Article
Chemistry, Physical
Jung Soo Lee, Young-Bum Chun, Won-Seok Ko
Summary: A new PtTi binary interatomic potential was developed by improving the existing interatomic potential, which successfully simulated the physical properties and phase transformations of PtTi alloy.
Article
Materials Science, Multidisciplinary
Mario Muralles, Joo Tien Oh, Zhong Chen
Summary: In this study, interatomic potentials for binary systems were developed using the second nearest-neighbor modified embedded-atom method (2NN MEAM) formalism. These potentials accurately reproduce essential physical properties and can be used to study multicomponent alloys and high entropy alloys, deepening our understanding of their unique properties at the atomic scale.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Biochemistry & Molecular Biology
Hyok-Chol Ri, Hak-Son Jin, Jong-Chol Cha, He Yang
Summary: The modified embedded atom method (MEAM) potentials were used to calculate mono- and bi-vacancy properties as well as phonon dispersions for hexagonal close-packed (HCP) metals Be, Co, Hf, Mg, and Re. The results show better agreement with experimental data compared to previous calculations with the unimproved embedded atom model.
JOURNAL OF MOLECULAR MODELING
(2021)
Article
Materials Science, Multidisciplinary
Henan Zhou, Doyl E. Dickel, Michael Baskes, Sungkwang Mun, Mohsen Asle Zaeem
Summary: A semi-empirical interatomic potential for bismuth based on the modified embedded-atom method (MEAM) has been developed, accurately reproducing physical properties and showing good agreement with experimental data and density functional theory calculations. This potential is useful for studying material and mechanical behaviors of pure bismuth under different conditions and lays the groundwork for developing potentials for bismuth alloys or compounds.
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2021)
Article
Chemistry, Physical
Joonho Ji, Byeong-Joo Lee
Summary: In this paper, a Li-Ni-O interatomic potential is developed to analyze and gain insight into cathode materials for Li-ion batteries. The potential is validated by reproducing fundamental properties and lithium diffusion characteristics in good agreement with experiments and first-principles calculations. It can be easily extended to other related systems and has significant application value in the Li-ion battery field.
JOURNAL OF POWER SOURCES
(2022)
Article
Multidisciplinary Sciences
Feihong Chu, Xianlin Qu, Yongcai He, Wenling Li, Xiaoqing Chen, Zilong Zheng, Miao Yang, Xiaoning Ru, Fuguo Peng, Minghao Qu, Kun Zheng, Xixiang Xu, Hui Yan, Yongzhe Zhang
Summary: The authors design a hybrid interface by tuning the pyramid apex-angle to improve the interfacial morphology of c-Si/a-Si:H in silicon solar cells. This hybrid interface prevents both c-Si epitaxial growth and nanotwin formation, leading to improved interfacial morphology. This method can be widely applied to all silicon-based solar cells without any additional industrial preparation processes.
NATURE COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Keita Nomoto, Xiang-Yuan Cui, Andrew Breen, Anna Ceguerra, Ivan Perez-Wurfl, Gavin Conibeer, Simon P. Ringer
Summary: Thermal annealing temperature has a significant effect on the growth and dopant distribution of Si nanocrystals. Raising the annealing temperature promotes the growth and increased phosphorus concentration of Si nanocrystals, but does not affect the incorporation of boron atoms. Boron atoms tend to locate at the interface between Si nanocrystals and the SiO2 matrix. Oxygen vacancies play a crucial role in regulating the growth and dopant distribution of Si nanocrystals.
Article
Physics, Applied
Susmita Biswas, Anupam Nandi, Ujjwal Ghanta, Biswajit Jana, Sumita Mukhopadhyay, Hiranmay Saha, Syed Minhaz Hossain
Summary: A colloidal suspension of silicon/silicon oxide core/shell nanoparticles was synthesized using a mechanochemical approach. The core size distribution was confirmed to be quasi-mono-dispersed, with optical properties dependent on excitation photon energy. The nanoparticles exhibited enhanced hot-carrier lifetime when embedded in a hard matrix, showing potential for applications in hot-carrier solar cells.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Physics, Applied
Dhanunjaya Munthala, A. Mangababu, S. V. S. Nageswara Rao, S. Pojprapai, A. P. Pathak, D. K. Avasthi
Summary: This study reports on the formation of silver nanoparticles induced by swift heavy ions embedded in hafnium oxide matrix, with research done on the evolution of particle properties using various techniques. It reveals the tunability of surface plasmon resonance wavelength up to 120 nm through ion fluence.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Multidisciplinary
Deepak K. Gupta, Fred van Keulen, Matthijs Langelaar
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2020)
Article
Engineering, Multidisciplinary
Elena De Lazzari, Sanne J. van den Boom, Jian Zhang, Fred van Keulen, Alejandro M. Aragon
Summary: Enriched finite element methods have been increasingly used for modeling problems involving material interfaces and cracks. While NURBS can accurately preserve interface geometries, they do not significantly improve the extraction of stress intensity factors for cracked specimens, and the complexity of exact geometry representation outweighs the benefits in low-order elements.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Emiel van de Ven, Can Ayas, Matthijs Langelaar, Robert Maas, Fred van Keulen
Summary: Additive manufacturing and topology optimization have a synergistic relationship, with TO providing high-performance parts that leverage the form freedom of AM; Recently, TO has been tailored towards AM by including a minimum allowable overhang angle as a design constraint to allow designs to be built without support structures. This study introduces an accessibility-aware overhang filter to improve part performance and convergence behavior.
INTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING
(2021)
Article
Computer Science, Interdisciplinary Applications
S. J. van den Boom, J. Zhang, F. van Keulen, A. M. Aragon
Summary: Smooth geometry description is crucial in design optimization, and combining level set description with a new enriched topology optimization methodology can generate correct topologies without the drawbacks of existing enriched methods.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2021)
Article
Instruments & Instrumentation
R. J. F. Bijster, F. van Keulen
Summary: Multilayer cantilever beams are utilized for measuring near-field radiative heat transfer, and analytical model is employed for design to enhance system performance. Constraints are placed on thermal noise, temperature drift, and spring constant, while maximizing optical reflectance and sensitivity.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2021)
Article
Engineering, Multidisciplinary
S. J. van den Boom, F. van Keulen, A. M. Aragon
Summary: An immersed enriched finite element method is proposed for analyzing phononic crystals with completely decoupled finite element meshes from geometry. The method effectively transforms non-conforming discretization into an enriched node-to-node periodic discretizations and eliminates the need for generating matching or fitted meshes during the design process. This approach shows the same performance as standard finite element analysis on fitted meshes in analyzing phononic crystals in structured meshes.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Grzegorz Misiun, Emiel van de Ven, Matthijs Langelaar, Hubert Geijselaers, Fred van Keulen, Ton van den Boogaard, Can Ayas
Summary: This study combines additive manufacturing simulation and topology optimization to propose a solution to the distortion issue in powder bed additive manufacturing, modeling and optimizing for two possible causes of failure. The formulated constraints were found to effectively prevent excessive part distortion and associated build failures.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2021)
Article
Engineering, Multidisciplinary
Jian Zhang, Fred van Keulen, Alejandro M. Aragon
Summary: The study proposes a fully immersed topology optimization procedure for designing structures with tailored fracture resistance in brittle materials under linear elastic fracture mechanics assumptions. By using a level set function and the Interface-enriched Generalized Finite Element Method (IGFEM), accurate structural responses are obtained. The technique approximates energy release rates (ERRs) of all potential cracks using topological derivatives after a single enriched finite element analysis, and demonstrates the ability to tailor fracture resistance through several numerical examples.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Computer Science, Interdisciplinary Applications
Coen Bakker, Lidan Zhang, Kristie Higginson, Fred van Keulen
Summary: This study focuses on optimizing the topology and layout of stiffened shells and plates by introducing modular design and density-based topology optimization. The method is able to generate clear topologies for any number of modules, demonstrating distinct layouts of stiffeners on the base shell or plate.
STRUCTURAL AND MULTIDISCIPLINARY OPTIMIZATION
(2021)
Article
Engineering, Mechanical
Yong Zhang, Marcel Tichem, Fred van Keulen
Summary: Metastructures composed of snapping beams can deform into stable states with different curvatures, and the beam thickness is crucial for tuning the snap-through response. Curvature can be adjusted by changing the beam height and span.
EXTREME MECHANICS LETTERS
(2022)
Article
Engineering, Multidisciplinary
S. Koppen, M. Langelaar, F. van Keulen
Summary: In this paper, a novel method is proposed to efficiently calculate responses and design sensitivities in multi-partition problems for gradient-based topology optimization. The method is applicable to various linear problems and shows particular effectiveness in the topology optimization of small-displacement multi-input-multi-output compliant mechanisms. Numerical experiments demonstrate its efficiency for large-scale multi-partition problems.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2022)
Article
Engineering, Mechanical
S. Koppen, M. Langelaar, F. van Keulen
Summary: Flexures are crucial in high-tech equipment for precise manipulation and measurement. This study proposes a novel topology optimization formulation for designing short-stroke flexures, based on strain energy measures. It demonstrates versatility in flexure types and additional design requirements.
MECHANISM AND MACHINE THEORY
(2022)
Article
Engineering, Manufacturing
R. Ranjan, Z. Chen, C. Ayas, M. Langelaar, F. Van Keulen
Summary: Overheating is a major issue in metal Additive Manufacturing (AM) processes, leading to poor surface quality, lack of dimensional precision, inferior performance and/or build failures. This study presents a 3D density-based topology optimization (TO) method that integrates a simplified AM thermal model and a thermal constraint to address the issue of local overheating during metal AM. The proposed physics-based method reduces the risk of overheating and delivers efficient designs compared to commonly used geometry-based TO methods.
ADDITIVE MANUFACTURING
(2023)
Article
Engineering, Multidisciplinary
Sanne J. van den Boom, Reza Abedi, Fred van Keulen, Alejandro M. Aragon
Summary: Phononic crystals can exhibit band gaps, which are frequency ranges with strong attenuation in the material. The working principle is based on destructive interference of waves reflecting from the periodic arrangement of material interfaces. However, the commonly used density-based representation in topology optimization methods leads to diffuse staircased boundaries, resulting in large and expensive optimization problems. This paper demonstrates the adverse effect of density-based boundary description and proposes a level set-based topology optimization procedure with an enriched finite element method for improved performance.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
Article
Engineering, Multidisciplinary
Weiming Wang, Fred van Keulen, Jun Wu
Summary: Additive manufacturing of metal parts often leads to distortion due to phase transformations and high temperature gradients. This paper proposes a computational framework that optimizes the fabrication sequence to minimize distortion in multi-axis additive manufacturing. By encoding the fabrication sequence using a continuous pseudo-time field and using gradient-based numerical optimization, the framework successfully reduces distortion by orders of magnitude compared to planar fabrication.
COMPUTER METHODS IN APPLIED MECHANICS AND ENGINEERING
(2023)
