Article
Materials Science, Multidisciplinary
Abhishek Arora, Rajat Arora, Amit Acharya
Summary: This study demonstrates the significantly different responses of metal thin films in compression and shear, and successfully simulates this behavior using the Mesoscale Field Dislocation Mechanics (MFDM) model without any modification or additional fitting parameters. This research represents a crucial theoretical advancement in the field of strain gradient plasticity models.
Article
Materials Science, Multidisciplinary
Nicole K. Aragon, Jamie D. Gravell, Ill Ryu
Summary: Research demonstrates that grain boundaries play a crucial role in nanostructured metals, influencing plastic deformation by controlling dislocation propagation. Different samples with high angle grain boundaries and coherent twin boundaries show distinct mechanical responses in plastic deformation.
Article
Engineering, Mechanical
Songjiang Lu, Qianhua Kan, Michael Zaiser, Zhenhuan Li, Guozheng Kang, Xu Zhang
Summary: This study examines the effects of grain size and dislocation source properties on the yield stress of ultrafine-grained polycrystals using three-dimensional multiscale discrete dislocation dynamics. The simulation demonstrates a nonmonotonic dependency of flow stress on dislocation source length and deviations from the classical Hall-Petch relationship in the grain size dependence of yield stress. The study provides insights into the controlling factors of yield stress in the ultrafine-grained regime and proposes a theoretical model to explain the combined effects of source length, grain size, and initial dislocation density.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Materials Science, Multidisciplinary
Alexander Bergsmo, Yilun Xu, Benjamin Poole, Fionn P. E. Dunne
Summary: The study found that non-metallic inclusions and twin boundaries are preferred locations for fatigue crack nucleation in polycrystalline Ni-based superalloys. Through a multi-scale modelling strategy, the mechanism of fatigue crack nucleation was analyzed, revealing the involvement of inclusion fracture, twin boundary slip activation, and the accumulation of local geometrically necessary dislocations. These factors ultimately lead to the formation of fatigue cracks.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2022)
Article
Materials Science, Multidisciplinary
Aleksandr V. Korchuganov, Konstantin P. Zolnikov, Dmitrij S. Kryzhevich
Summary: This paper investigates the deformation behavior of a gradient grained FeNi sample under uniaxial tension using molecular dynamics simulations. The study shows that plasticity of the sample develops through sequential activation of different mechanisms including structural defect generation, grain boundary migration, and grain boundary sliding. Plasticity onset is provided by partial dislocations that produce stacking faults in large grains. Other mechanisms such as twinning and grain boundary migration gradually affect smaller grains.
Article
Materials Science, Multidisciplinary
Tawqeer Nasir Tak, Aditya Prakash, Shyam M. Keralavarma, Indradev Samajdar, P. J. Guruprasad
Summary: This study extended a single crystal dislocation creep model into polycrystalline ensemble, and simulated the mechanical behavior of polycrystalline aluminum. The results showed the relationship between strain rate and temperature, stress, and grain size, and revealed the controlling mechanism of dislocation interactions with static obstacles and grain boundaries.
JOURNAL OF THE MECHANICS AND PHYSICS OF SOLIDS
(2023)
Article
Nanoscience & Nanotechnology
Zhanfeng Wang, Junjie Zhang, Jinzhong Lu
Summary: This study investigates the deformation mechanisms of single crystal and bicrystal Cu workpieces under nanoindentation through experiments and molecular dynamics simulations. The results highlight the significant role of dislocation-grain boundary interactions and crystallographic orientation on the mechanical response of the materials.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Mechanical
Wenbo Dong, Hengjie Liu, Juan Du, Xu Zhang, Minsheng Huang, Zhenhuan Li, Ziguang Chen, Florin Bobaru
Summary: This paper presents a solution for discrete dislocation dynamics problems using the peridynamic-based superposition framework. The new scheme can simulate arbitrary domains without explicitly tracking boundaries and interfaces. The numerical results show that the new scheme is more accurate near dislocation cores compared to existing schemes.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Chemistry, Physical
Pandong Lin, Shugang Cui, Junfeng Nie, Lei He, Wendong Cui
Summary: This study investigates the interactions between displacement cascades and three types of structures (dislocations, dislocation loops, and grain boundaries) in BCC-Fe through molecular dynamics simulations. The results show that displacement cascades in systems interacting with these three types of structures tend to produce more defects. The changes in the atomic structures of dislocations, dislocation loops, and grain boundaries after displacement cascades are analyzed to understand the effects of irradiation damage on them.
Article
Materials Science, Multidisciplinary
Masato Wakeda, Takahito Ohmura
Summary: This study evaluates the resistance for dislocation transmission across tilt/twist low-angle grain boundaries (LAGBs) and found that the twist LAGB is a stronger obstacle compared to the tilt LAGB. The barrier effect of the grain boundary (GB) on the transmission is stronger for the screw component than for the edge component. The dominant factors of the GB-strengthening effect in LAGB are the incident lattice dislocation type, the structure of GB dislocations, and dislocation-dislocation reactions.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Kai Hu, Jun Yi, Bo Huang, Xilei Bian, Gang Wang
Summary: This study overcomes the trade-off between strength and ductility in pure nickel materials by using grain boundary relaxation and optimizing grain size. The results show that grain boundary relaxation can improve both tensile strength and uniform elongation of nickel, and enhance the plastic deformation through controlling dislocation activities.
APPLIED MATERIALS TODAY
(2022)
Article
Nanoscience & Nanotechnology
Yang Su, Thanh Phan, Liming Xiong, Josh Kacher
Summary: This paper combines in situ high-resolution electron backscattered diffraction (EBSD) with concurrent atomistic-continuum (CAC) simulations to investigate the interactions between dislocation-mediated slip and grain boundaries (GBs) in Ni. The study shows that the local stress at slip-GB intersections initially increases with the pileup of dislocations and remains high, even after the nucleation of dislocations in the neighboring grain. The local stress only relaxes when the nucleated dislocations propagate away from the GB due to more incoming dislocations participating in the pileup. The relaxation of local stress is accompanied by the reconfiguration of atomic-scale GB structure, which not only affects subsequent dislocation transmission but also the configuration of dislocations away from the GB. These findings highlight the importance of incorporating local stress history in higher length scale models, such as crystal plasticity finite element.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Multidisciplinary
Sheng Qian, Yifeng Ni, Yi Gong, Fan Yang, Qi Tong
Summary: This study finds that using a gradient nanograined structure can enhance the damping capacity of metals. The GB orientations in the gradient grains can facilitate GB sliding, thus increasing the damping capacity. This structure can also maintain the level of material strength and achieve a synergy of strength, ductility, and damping.
Article
Materials Science, Multidisciplinary
Ronan Madec, Luc Portelette, Bruno Michel, Jonathan Amodeo
Summary: The mechanical behavior of UO2 single crystal, especially the unexpected multi-slip observations, has been studied in this research. A multi-scale model based on composite slip is proposed, in which dislocation density can be transferred from primary slip systems to secondary systems under the effect of cross-slip. This approach accurately describes the anisotropic mechanical response of UO2 single crystal, providing new insights into the links between dislocation microstructures and mechanical properties. The composite slip mechanism appears to be a candidate for explaining unexpected plastic behaviors in complex materials with multiple slip modes, suggesting that slip activation may be more complex than in usual constitutive laws.
Article
Materials Science, Multidisciplinary
Qiongjiali Fang, Frederic Sansoz
Summary: This study investigates the effects of grain boundary (GB) strain accommodation on plastic deformation in columnar-grained nanocrystalline nanotwinned (nt) face-centered cubic metals. The research findings show that CTB strengthening effects are increasingly more pronounced in columnar-grained nt metals as their shear modulus increases.
Article
Nanoscience & Nanotechnology
Jie Zhang, Xiaoyang Chen, MingJian Ding, Jiaqiang Chen, Ping Yu
Summary: This study enhances the compositional inhomogeneity of relaxor ferroelectric thin films to improve their dielectric temperature stability. The prepared films exhibit a relatively high dielectric constant and a very low variation ratio of dielectric constant over a wide temperature range.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xiaoyu Chen, Ranran Zhang, Hao Zou, Ling Li, Qiancheng Zhu, Wenming Zhang
Summary: Polyaniline-manganese dioxide composites exhibit high conductivity, long discharge platform, and stable circulation, and the specific capacity is increased by providing additional H+ ions to participate in the reaction.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xutao Huang, Yinping Chen, Jianjun Wang, Gang Lu, Wenxin Wang, Zan Yao, Sixin Zhao, Yujie Liu, Qian Li
Summary: This study aims to establish a novel approach to better understand and predict the behavior of materials with multi-scale lamellar microstructures. High-resolution reconstruction and collaborative characterization methods are used to accurately represent the microstructure. The mechanical properties of pearlite are investigated using crystal plasticity simulation and in-situ scanning electron microscopy tensile testing. The results validate the reliability of the novel strategy.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Cheng Chen, Fanchao Meng, Jun Song
Summary: This study systematically investigated the unfaulting mechanism of single-layer interstitial dislocation loops in irradiated L12-Ni3Al. The unfaulting routes of the loops were uncovered and the symmetry breaking during the unfaulting processes was further elucidated. A continuum model was formulated to analyze the energetics of the loops and predict the unfaulting threshold.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Darshan Bamney, Laurent Capolungo
Summary: This work investigates the formation of adjoining twin pairs (ATPs) at grain boundaries (GBs) in hexagonal close-packed (hcp) metals, focusing on the co-nucleation (CN) of pairs of deformation twins. A continuum defect mechanics model is proposed to study the energetic feasibility of CN of ATPs resulting from GB dislocation dissociation. The model reveals that CN is preferred over the nucleation of a single twin variant for low misorientation angle GBs. Further analysis considering GB character and twin system alignment suggests that CN events could be responsible for ATP formation even at low m' values.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Bing Han, Zhengqian Fu, Guoxiang Zhao, Xuefeng Chen, Genshui Wang, Fangfang Xu
Summary: This study investigates the behavior of electric-field induced antiferroelectric to ferroelectric (AFE-FE) phase transition and reveals the evolution of atomic displacement ordering as the cause for the transition behavior changing from sharp to diffuse. The novel semi-ordered configuration results from the competing interaction between long-range displacement modulation and compositional inhomogeneity, which leads to a diffuse AFE-FE transition while maintaining the switching field.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Akib Jabed, Golden Kumar
Summary: This study demonstrates that cryogenic rejuvenation promotes homogeneous-like flow and increases ductility in metallic glass samples. Conversely, annealing has the opposite effect, resulting in a smoother fracture surface.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Xin Ji, Yan Chong, Satoshi Emura, Koichi Tsuchiya
Summary: A heterogeneous microstructure in Ti-15Mo-3Al alloy with heterogeneous distributions of Mo element and omega(iso) precipitates has achieved a four-fold increase in tensile ductility without a loss of tensile strength, by blocking the propagation of dislocation channels and preventing the formation of micro-cracks.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Amit Samanta, Prasanna Balaprakash, Sylvie Aubry, Brian K. Lin
Summary: This study proposes a combined large-scale first principles approach with machine learning and materials informatics to quickly explore the chemistry-composition space of advanced high strength steels (AHSS). The distribution of aluminum and manganese atoms in iron is systematically explored using first principles calculations to investigate low stacking fault energy configurations. The use of an automated machine learning tool, DeepHyper, speeds up the computational process. The study provides insights into the distribution of aluminum and manganese atoms in systems containing stacking faults and their effects on the equilibrium distribution.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Guowei Zhou, Yuanzhe Hu, Zizheng Cao, Myoung Gyu Lee, Dayong Li
Summary: In this work, a physics-constrained neural network is used to predict grain-level responses in FCC material by incorporating crystal plasticity theory. The key feature, shear strain rate of slip system, is identified based on crystal plasticity and incorporated into the loss function as physical constitutive equations. The introduction of physics constraints accelerates the convergence of the neural network model and improves prediction accuracy, especially for small-scale datasets. Transfer learning is performed to capture complex in-plane deformation of crystals with any initial orientations, including cyclic loading and arbitrary non-monotonic loading.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Pengfei Yang, Qichang Li, Zhongying Wang, Yuxiao Gao, Wei Jin, Weiping Xiao, Lei Wang, Fusheng Liu, Zexing Wu
Summary: In this study, the HER performance of Ru-based catalysts is significantly improved through the dual-doping strategy. The obtained catalyst exhibits excellent performance in alkaline freshwater and alkaline seawater, and can be stably operated in a self-assembled overall water splitting electrolyzer.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Ilias Bikmukhametov, Garritt J. Tucker, Gregory B. Thompson
Summary: Depositing a Ni-1at. % P film can facilitate the formation of multiple quintuple twin junctions, resulting in a five-fold twin structure and a pentagonal pyramid surface topology. The ability to control material structures offers opportunities for creating novel surface topologies, which can be used as arrays of field emitters or textured surfaces.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Zening Yang, Weiwei Sun, Zhengyu Sun, Mutian Zhang, Jin Yu, Yubin Wen
Summary: Multicomponent oxides (MCOs) have wide applications and accurately predicting their thermal expansion remains challenging. This study introduces an innovative attention-based deep learning model, which achieves improved performance by using two self-attention modules and demonstrates adaptability and interpretability.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Ze Liu, Cai Chen, Yuanxun Zhou, Lanting Zhang, Hong Wang
Summary: This study attempts to address the gap in cooling rates between thin film deposition and bulk metallic glass (BMG) casting by correlating the glass-forming range (GFR) determined from combinatorial materials chips (CMCs) with the glass-forming ability (GFA) of BMG. The results show that the full-width at half maximum (FWHM) of the first sharp diffraction peak (FSDP) is a good indicator of BMG GFA, and strong positive correlations between FWHM and the critical casting diameter (Dmax) are observed in various BMG systems. Furthermore, the Pearson correlation coefficients suggest possible similarities in the GFA natures of certain BMG pairs.
SCRIPTA MATERIALIA
(2024)
Article
Nanoscience & Nanotechnology
Mike Schneider, Jean-Philippe Couzinie, Amin Shalabi, Farhad Ibrahimkhel, Alberto Ferrari, Fritz Koermann, Guillaume Laplanche
Summary: This work aims to predict the microstructure of recrystallized medium and high-entropy alloys, particularly the density and thickness of annealing twins. Through experiments and simulations, a database is provided for twin boundary engineering in alloy development. The results also support existing theories and empirical relationships.
SCRIPTA MATERIALIA
(2024)