Article
Nanoscience & Nanotechnology
Q. Zhang, X. Jin, X. H. Shi, J. W. Qiao, P. K. Liaw
Summary: The CrCoNi medium-entropy alloy exhibits higher plastic strength with slow cooling due to the inconsistency between residual stress and short-range orderings. Quantification of the roles of residual stress and SROs reveals that SROs contribute more to the strengthening effect.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
E. Antillon, C. Woodward, S. Rao, B. Akdim
Summary: Atomistic methods were used to anneal two BCC chemically complex alloys to evaluate the effect of chemical short-range order on alloy strength. It was found that annealing led to a softening of the BCC quaternary alloy but had minimal effect on solid solution strengthening in the ternary alloy. Results were modeled using an extension of the Suzuki model of substitutional solid solution strengthening, with good agreement between the model results and direct atomistic simulation data.
Article
Materials Science, Multidisciplinary
Nanjun Liu, Xintao Tian, Qiaojun Liu, Bin Gan, Jun Ding, En Ma, Zhangjie Wang
Summary: Nanoindentation is widely used to study the effect of CSRO on the strength of high- and medium-entropy alloys. In this study, the mechanism of extremely small pop-in events during nanoindentation was experimentally captured, revealing that the formation of stacking faults and nanotwins is responsible. It was also found that the twinning stress is elevated in alloys with higher CSRO levels.
SCIENCE CHINA-MATERIALS
(2023)
Article
Chemistry, Physical
Yongzhi Xi, Xiaofeng Yang, Xunlu Yin, Xinxin Liu, Xiancheng Zhang, Hao Chen
Summary: The interactive strengthening effect of twin boundary and local chemical ordering (LCO) structure was investigated in CoCrNi medium-entropy alloy (MEA). The results showed that both LCO and twin boundary enhance the hardness of the alloy. When LCO and twin boundary are coupled, a concurrent strengthening effect occurs, significantly improving the hardness. The twin boundary provides a slipping path for dislocations, while the LCO structure limits the slip of dislocations on the twin boundary.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Wei Chen, Lin Li, Qiang Zhu, Houlong Zhuang
Summary: Complex concentrated alloys (CCAs) have attracted significant attention for their wide range of applications and novel properties. Chemical short-range ordering (CSRO) in CCAs plays a crucial role in understanding their properties and phase stability. This article reviews recent experimental efforts in identifying and characterizing CSRO in CCAs, and discusses theoretical and computational techniques, such as density functional theory (DFT) and molecular dynamics (MD), used to investigate CSRO effects.
Article
Multidisciplinary Sciences
Xuefei Chen, Qi Wang, Zhiying Cheng, Mingliu Zhu, Hao Zhou, Ping Jiang, Lingling Zhou, Qiqi Xue, Fuping Yuan, Jing Zhu, Xiaolei Wu, En Ma
Summary: The study provides direct experimental evidence of chemical short-range atomic-scale ordering (CSRO) in a VCoNi medium-entropy alloy through diffraction and electron microscopy analysis. The research demonstrates that using specific crystallographic directions can reveal CSRO in face-centred-cubic VCoNi concentrated solution, offering insights into atomic packing configuration and dislocation interactions enhanced by CSROs.
Article
Nanoscience & Nanotechnology
Claudio Geraldo Schon
Summary: Short-range order (SRO) strengthening in alloys is attributed to increased resistance to dislocation slip caused by breaking favorable bonds. This study focuses on the dissipated energy due to the formation of a diffuse antiphase boundary (APB), showing that SRO strengthening is important in defining the friction stress on gliding dislocations.
SCRIPTA MATERIALIA
(2021)
Article
Materials Science, Multidisciplinary
Lingling Zhou, Qi Wang, Jing Wang, Xuefei Chen, Ping Jiang, Hao Zhou, Fuping Yuan, Xiaolei Wu, Zhiying Cheng, En Ma
Summary: This study provides experimental evidence for the existence of chemical short-range order (CSRO) in CrCoNi alloy through electron diffraction and atomic-resolution chemical mapping. The spatial correlations between different atomic pairs are revealed through quantitative covariance analysis. The findings are significant for understanding CSRO in multi-principal-element solutions.
Article
Materials Science, Multidisciplinary
Xuefei Chen, Fuping Yuan, Hao Zhou, Xiaolei Wu
Summary: In this study, we observed extra diffuse scattering from CSRO in the [111] and [112] directions in a VCoNi MEA using electron diffraction. We successfully constructed the L1(1)-type structure motif for CSRO and derived the flat cuboid spatial shape of CSRO through diffractions under different zone axis. Furthermore, we demonstrated methods to identify CSRO in lattice images.
MATERIALS RESEARCH LETTERS
(2022)
Review
Materials Science, Multidisciplinary
Xiaolei Wu
Summary: High-entropy alloys are complex solid solutions with chemical short-range orders that differ fundamentally from traditional alloys. These short-range orders play a crucial role in dislocation behavior and mechanical properties. However, it has been challenging to experimentally observe and characterize these short-range orders. Recently, the use of advanced transmission electron microscopy has allowed for the identification and characterization of these chemical short-range orders in high-entropy alloys, providing valuable insights into the relationship between microstructure and mechanical properties.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Chemistry, Physical
Hui Zheng, Lauren T. W. Fey, Xiang-Guo Li, Yong-Jie Hu, Liang Qi, Chi Chen, Shuozhi Xu, Irene J. Beyerlein, Shyue Ping Ong
Summary: In this study, the influence of short-range ordering (SRO) on dislocation glide in MoNbTi and TaNbTi RMPEAs is investigated using a multi-scale modeling approach. The results show that MoNbTi exhibits a higher degree of SRO than TaNbTi, and the local composition directly affects the unstable stacking fault energies (USFEs). Increasing SRO leads to higher mean USFEs and stress required for dislocation glide. Gliding dislocations experience significant hardening due to pinning and depinning caused by random compositional fluctuations, with higher SRO decreasing the degree of USFE dispersion and amount of hardening. Lastly, the applied stress is shown to affect the morphology of an expanding dislocation loop.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Yi-Siang Lin, Ying-Chou Lu, Chun-Hway Hsueh
Summary: A series of (CoCrNi)100-xGdx (x = 0/0.1/0.3/0.5/1.0) medium entropy alloys (MEAs) were fabricated and the effects of Gd additions on the microstructures and mechanical properties of CoCrNi MEAs were studied. With increasing Gd concentration, the phase transformed from face-centered cubic (FCC) to hexagonal close-packed (HCP) precipitates in the FCC matrix. The CoCrNi99.5Gd0.5 MEA exhibited significantly enhanced mechanical properties compared to the single-phase CoCrNi MEA.
Article
Physics, Applied
Michael Xu, Shaolou Wei, C. Cem Tasan, James M. LeBeau
Summary: The presence of short-range chemical order in metals can significantly affect their mechanical behavior. However, determining the distribution of chemical order in complex alloy systems is challenging. In this study, we use aberration corrected scanning transmission electron microscopy (STEM) and spatial statistics methods to identify and quantify chemical order in the BCC-TiVNbHf(Al) system. Through null hypothesis tests, we differentiate the experimental data from random chemical distribution and find that the experimental results deviate significantly from both random solid solution and fully ordered structures. We also observe and quantify the enhancement of short-range order with the addition of Al. These findings provide valuable insights into the local chemical order in TiVNbHf(Al) alloys and demonstrate the usefulness of spatial statistics in characterizing nanoscale short-range order in complex systems.
APPLIED PHYSICS LETTERS
(2023)
Article
Physics, Fluids & Plasmas
Chae Woo Ryu, Takeshi Egami
Summary: This article discusses the influence of short-range order (SRO) and medium-range order (MRO) on the physical properties of liquids and glasses, showing that MRO plays a critical role in the viscosity of supercooled liquids.
Article
Physics, Condensed Matter
LiJun Yuan, Ran Tao, PengCheng Wen, Jing Li, Shen Wang, Da Li
Summary: The strengthening effect and micro mechanism of CSRO on FCC FeNiCrCoAlx alloys were studied using Molecular Dynamics simulation method. The results show that CSRO can increase the alloy's yield strength, reduce dislocation slip, and has a more significant strengthening effect at room and low temperatures.
PHYSICA B-CONDENSED MATTER
(2023)
Article
Engineering, Mechanical
Xue-Wei Zhang, Jian-Feng Wen, Xian-Cheng Zhang, Xiao-Gang Wang, Shan-Tung Tu
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2019)
Article
Engineering, Mechanical
Tao Wang, Jian-Feng Wen, Yun-Jae Kim, Shan-Tung Tu
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2020)
Article
Engineering, Mechanical
Yuhan Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2020)
Article
Engineering, Mechanical
Valery Shlyannikov, Dmitry Kosov, Dmitry Fedorenkov, Xian-Chen Zhang, Shan-Tung Tu
Summary: The investigation focused on crack propagation under creep-fatigue interaction in C(T) specimens of P2M steel, with numerical calculations determining stress-strain state fields and stress intensity factors at the crack front. The experimental results were interpreted using traditional and new cyclic fracture diagrams, showing differences in crack growth behavior under creep-dominated stress intensity factors. The crack growth rate increased monotonically in specimens with the same geometry under creep-fatigue interaction compared to harmonic fatigue, indicating a significant increase in total crack growth rate when fatigue and creep contributions are combined.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2021)
Article
Engineering, Multidisciplinary
Wei Peng, Wenchun Jiang, Qiang Jin, Yu Wan, Yun Luo, Linchang Ren, Kai Zhang, Shan-Tung Tu
Summary: The study investigates the welding residual stresses in a cracked head-cylinder joint of a large rectifying tower. Factors such as welding layer sequence, cover welding direction, and weld reinforcement were found to have significant effects on stress distribution. Unreasonable welding processes and structural discontinuities were identified as the main reasons for cracking, while proper welding techniques and sequences can alleviate stress concentration issues.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2021)
Article
Engineering, Multidisciplinary
J. Z. He, G. Z. Wang, S. T. Tu, F. Z. Xuan
Summary: The study established creep crack initiation time equations for a Cr-Mo-V steel at 566 degrees C under different constraints, and predicted crack initiation times for specimens with different geometries and dimensions under various constraint levels. The predictions aligned well with experimental data and finite element simulations, suggesting the applicability of the methods for high-temperature components under static loads.
INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING
(2021)
Article
Engineering, Mechanical
Kai Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
Summary: This paper investigates the effects of crack sizes, plate geometries, and material properties on the creep fracture mechanics parameter C* for plate structures with semi-elliptic surface cracks under different loads. Creep influence functions Hc were obtained to calculate C* values, which were fitted into equations and verified through finite element calculations. The solutions for C* obtained from these equations are suitable for various crack sizes, plate geometries, and materials.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Kai Wang, Guozhen Wang, Shantung Tu, Fuzhen Xuan
Summary: In this study, the authors investigated the unified creep constraint parameter for plate structures with different surface crack sizes using finite element analysis. They analyzed the effects of material properties, crack sizes, loading modes, and plate thickness on the parameter and proposed a method for assessing the life of cracked plates.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Le Xu, Run-Zi Wang, Lei He, Xian-Cheng Zhang, Shan-Tung Tu, Hideo Miura, Takamoto Itoh
Summary: Investigations into creep-fatigue life and failure mechanisms are crucial for ensuring structural integrity. This study performed strain-controlled fatigue and creep-fatigue tests at different temperatures and analyzed the microstructure evolution. Results showed that strain energy density had better relevance than ductility in relation to creep failure. A temperature-dependent critical strain energy density and an equivalent failure strain energy density, considering geometric effect, were incorporated into the current energy-based model, enabling scatter in creep-fatigue life within a factor of 1.5. Microstructure observations revealed that multi-slip activations and severe slip interactions were responsible for lifetime reductions under creep-fatigue conditions.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2022)
Article
Engineering, Mechanical
Jinyong Xiao, Guozhen Wang, Fuzhen Xuan, Shantung Tu
Summary: In this study, the relationship between ductile fracture toughness and a new unified constraint parameter A(d)* for bi-material interfaces with different mechanical mismatches was investigated. The results showed that both increasing crack depth and mechanical mismatch level led to a decrease in the J-R curves and fracture toughness of bi-material interfaces. A general correlation equation between fracture toughness and constraint parameter was obtained, which can be used to predict fracture toughness in different material and geometric constraint situations.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Kang-Kang Wang, Jian-Feng Wen, Xian-Xi Xia, Run-Zi Wang, Guo-Dong Zhang, Xian-Cheng Zhang, Shan-Tung Tu
Summary: This study evaluates the damages caused by cyclic loading and high temperature effects and proposes an improved life assessment method. The models based on the LDS rule perform well, and the developed oxidation damage equation improves the accuracy of life prediction. Model selection criteria are recommended to evaluate the prediction capabilities of the models.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Binhan Sun, Xizhen Dong, Jianfeng Wen, Xian-Cheng Zhang, Shan-Tung Tu
Summary: Hydrogen embrittlement is the sudden loss of mechanical property of a material due to the ingress of hydrogen atoms and interactions with the material. The development of microstructure design strategies to mitigate hydrogen embrittlement is challenging due to limited understanding of its fundamental mechanisms. However, recent progress has been made in this field. This article provides an overview of established microstructural approaches to mitigate hydrogen embrittlement in metallic materials, comparing their effectiveness and applicability. The operating mechanisms, advantages, and limitations of these approaches are also discussed to guide future development and successful industrial application.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
Article
Engineering, Mechanical
Chuanyang Lu, Peng Wang, Silu Zheng, Xijia Wu, Rong Liu, Yanming He, Jianguo Yang, Zengliang Gao, Shan-Tung Tu
Summary: To ensure the structural integrity of the nuclear reactor pressure vessel (RPV) during severe accidents, in-vessel retention (IVR) is essential for nuclear power generation as a carbon-neutral energy source. This study develops a simplified deformation-mechanism-based true-stress (DMTS) model to accurately predict the creep behavior and life of SA508 Gr.3 steel, a typical RPV material, above the phase transformation temperatures. Experimental observations show that the simplified DMTS model achieves excellent agreement with the predicted time to specific creep strain and rupture, compared to empirical methods such as Orr-Sherby-Dorn (OSD) and Larson-Miller (LM). Metallurgical examinations are conducted to discuss the controlling deformation mechanisms, providing a physical basis for the model development and application.
FATIGUE & FRACTURE OF ENGINEERING MATERIALS & STRUCTURES
(2023)
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)
