Article
Engineering, Mechanical
Xu Zhang, Yang Gui, Minjie Lai, Xiaochong Lu, Ji Gu, Feng Wang, Tao Yang, Zhangwei Wang, Min Song
Summary: The microstructures, mechanical properties, and deformation substructures of gradient Mo0.3NiCoCr medium-entropy alloys with very coarse grain size created by pre-torsion have been investigated. The strength of these alloys increases with the increase of torsion angle, while the tensile elongation remains the same, suggesting the enhanced strength-ductility synergy. The combination of experimental characterization and theoretical modeling enables to clarify the underlying strengthening and strain hardening mechanisms, providing guidance for optimizing the mechanical performance of structural materials via tuning the design of gradient structure.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Nanoscience & Nanotechnology
Bo Li, Kaisheng Ming, Kang Tu, Zonglin Li, Lichen Bai, Shijian Zheng
Summary: A medium-entropy alloy containing niobium has been designed, which exhibits excellent mechanical properties and good ductility. The alloy is strengthened through the combined effects of nanoprecipitates, stacking faults, and nano-twins. The introduction of high-density stacking faults and nano-twins, as well as the precipitation of niobium-rich gamma '' nanoprecipitates, contribute to the enhancement of flow stress and the improvement of ultimate tensile strength and ductility.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Materials Science, Multidisciplinary
Xiaochong Lu, Yang Gui, Zhenghong Fu, Ni Ao, Shengchuan Wu, Xu Zhang
Summary: Surface mechanical attrition treatment (SMAT) was used to enhance the strength of metastable high entropy alloys (MHEAs) without sacrificing ductility. The study revealed the synergetic extra-strengthening effect caused by the gradient microstructures generated by SMAT and the hetero-deformation induced (HDI) hardening mechanism, providing guidance for the mechanical property design of MHEAs.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Multidisciplinary
Zibing An, Shengcheng Mao, Yinong Liu, Hao Zhou, Yadi Zhai, Zhiyong Tian, Cuixiu Liu, Ze Zhang, Xiaodong Han
Summary: This study investigated a multi-mechanism approach to enhancing the mechanical properties of a CoCrFeMnNi high-entropy alloy through non-equiatomic alloy design and processing. The alloy exhibited improved yield strength, tensile strength, and uniform elongation, as well as significantly increased toughness after rotationally accelerated shot peening treatment. The enhancement in strength was attributed to various strengthening mechanisms associated with the heterogeneous microstructure of the alloy. The occurrence of multiple deformation mechanisms contributed to achieving suitable strain hardening and ensuring steady plastic deformation for high toughness.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
Dongpeng Hua, Xiaorong Liu, Wan Wang, Qing Zhou, Qiaosheng Xia, Shuo Li, Junqin Shi, Haifeng Wang
Summary: In this study, the atomistic formation mechanism of the three-dimensional hierarchical twins in CoCrNi was investigated using molecular dynamics simulations. The effects of strain rate and deformation temperature were found to be important factors. Chemical inhomogeneity in CoCrNi can reduce the necessary kink height for conjugate twins, promoting the formation of twin networks. At room temperature, plastic deformation is dominated by primary twins and conjugate slips at a relatively lower strain rate. Higher strain rates activate hierarchical twins. At cryogenic temperatures, hierarchical twins are promoted within a large range of strain rates. The study provides insights into the twinning behavior and offers guidance for designing alloys with excellent mechanical performance by tuning microstructures.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Longfei Zeng, Luming Zeng, Peng Xu, Weijiang Liu, Tongxiang Liang, Weirong Li, Xuehui Zhang
Summary: Gradient microstructural design is a new strategy for enhancing the strength-ductility synergy of high/medium entropy alloys. This study reports a three-level gradient hierarchical nanostructure in Al0.3CoCrFeNi HEA achieved through ultrasonic surface rolling processing and aging treatment, which significantly increases yield strength without sacrificing ductility.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Engineering, Mechanical
Fengchao An, Junhua Hou, Jikui Liu, Bingnan Qian, Wenjun Lu
Summary: The degradation of ductility in low-temperature annealed face centered cubic (FCC) based alloys due to intermetallic phase embrittlement can be overcome by implementing brittle intermetallic phase (x) shearing and deformation twins in an equiatomic CoNiV medium entropy alloy (MEA) with high stacking fault energy. This approach improves the true ultimate tensile strengths and flow stress, which in turn enhances the deformability of the MEA. The combination of deformable intermetallic phase and high stress deformation twins proposes a new strengthening mechanism for improving the mechanical properties of FCC based alloys.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Ruolan Shi, Bo Song, Dabiao Xia, Tingting Liu, Qingshan Yang, Ning Guo, Shengfeng Guo
Summary: In this study, initial {10-12} twins were induced in the extruded AZ31 rod through pre-compression along the extrusion direction. The effects of these initial twins on twinning behavior during torsion were thoroughly investigated. The combination of pre-compression and torsion increased the relative proportions of specific twin boundaries. The transformation mechanisms involved basal slip, growth of initial twins, formation of new twin variants, and detwinning. Furthermore, the influence of pre-compression on torsion properties was also discussed.
MATERIALS CHARACTERIZATION
(2023)
Article
Chemistry, Physical
Payam Edalati, Abbas Mohammadi, Mostafa Ketabchi, Kaveh Edalati
Summary: Dual-phase HEAs have attracted significant attention due to their promising mechanical properties, and experimental investigation on the AlFeCoNiCu alloy reveals diverse microstructural evolution behaviors of the two phases during plastic deformation, leading to a high microhardness of 495 Hv under high-pressure torsion.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Nanoscience & Nanotechnology
Lijing Lin, Xin Xian, Zhihong Zhong, Kuijing Song, Chengyong Wang, Guoqiang Wang, Yucheng Wu, Peter K. Liaw
Summary: The dual-phase FeCoCrMn alloy with alternating lamellar FCC and sigma phases showed high compression yield strength and limited ductility. Improved thermal activation process and strength decline at elevated temperatures were responsible for the increased ductility and decreased yield strength. Comparison of yield strength with other high-entropy alloys was also made.
ADVANCED COMPOSITES AND HYBRID MATERIALS
(2022)
Article
Chemistry, Physical
Xuanliang Chen, Minho O, Equo Kobayashi
Summary: This study applied cyclic deformation to an Al-Mg-Cu alloy and found that it increased the strength and ductility of the alloy by introducing dislocations and promoting cluster formation. The aging behaviors of the cyclically-strengthened (CS) samples were studied, and it was found that recovery and precipitation promotion occurred regardless of pre-aging. Pre-aged CS samples showed higher strength, but interestingly, after subsequent aging, the mechanical properties of pre-aged and non-pre-aged CS samples became the same.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Lou Li-Yan, Chen Shu-nan, Liu Yi, Ji Gang, Chen Hai-Dong, Jia Yun-Jie, Li Chang-Jiu, Li Cheng-Xin
Summary: A novel lightweight refractory high entropy alloys AlxCrNbTiV have been prepared by vacuum arc melting. The alloys exhibit a BCC phase with significant dendrite structure and a low density. The addition of Al enhances the hardness of the alloys. Al0.2CrNbTiV alloy shows a good combination of strength and ductility at room temperature, while Al0.5CrNbTiV and Al0.8CrNbTiV alloys exhibit typical brittle behavior. The hot compression process activates both DDRX and CDRX, resulting in softening and increased ductility of the alloys. The theoretical yield stress of AlxCrNbTiV is calculated, indicating that the degree of solid solution affects the accuracy of estimation.
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
(2022)
Article
Chemistry, Physical
Hoang-Giang Nguyen, Te-Hua Fang, Dinh-Quan Doan
Summary: The impact of temperature and strain rates on the cyclic plasticity of AlCrCuFeNi high entropy alloy (HEA) was investigated using molecular dynamics (MD) simulations. The results revealed that interactions between partial dislocations in the HEA caused lattice disorders, which minimized the Bauschinger effect. The study also highlighted the influence of temperature, strain rates, and grain boundaries on lattice disorder and provided new insights into the deformation mechanism of AlCrCuFeNi HEA.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Engineering, Mechanical
Feng He, Zhongsheng Yang, Shaofei Liu, Da Chen, Weitong Lin, Tao Yang, Daixiu Wei, Zhijun Wang, Jincheng Wang, Ji-jung Kai
Summary: A Ni2CoCrFeTi0.24Al0.2 HEA was developed with a yield strength of approximately 1.3 GPa and tensile elongation of 20% through single-step heat treatment. The excellent strength-ductility combination is attributed to the grain scale heterogeneous structure with L1(2) precipitates ranging from 10 to 100 nm. Additionally, the efficient hetero-deformation induced strain hardening effect allows for the good ductility of the HEA.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Chemistry, Physical
J. Y. Zhang, B. Xiao, Q. Li, B. X. Cao, J. X. Hou, S. F. Liu, J. X. Zhang, W. C. Xiao, J. H. Luan, Y. L. Zhao, C. T. Liu, T. Yang
Summary: In this study, the microstructural evolution and mechanical behavior of (Ni2Co2FeCr)(92)Al4Nb4 HEAs alloy at different aging temperatures were systematically investigated. The results showed that the aging temperature had a significant impact on the phase structure and mechanical properties of the alloy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
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)