1
|
Walsh F, Zhang M, Ritchie RO, Asta M, Minor AM. Multiple origins of extra electron diffractions in fcc metals. SCIENCE ADVANCES 2024; 10:eadn9673. [PMID: 39093961 PMCID: PMC11296326 DOI: 10.1126/sciadv.adn9673] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 06/27/2024] [Indexed: 08/04/2024]
Abstract
Diffuse intensities in the electron diffraction patterns of concentrated face-centered cubic solid solutions have been widely attributed to chemical short-range order, although this connection has been recently questioned. This article explores the many nonordering origins of commonly reported features using a combination of experimental electron microscopy and multislice diffraction simulations, which suggest that diffuse intensities largely represent thermal and static displacement scattering. A number of observations may reflect additional contributions from planar defects, surface terminations incommensurate with bulk periodicity, or weaker dynamical effects.
Collapse
Affiliation(s)
- Flynn Walsh
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mingwei Zhang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Davis, Davis, CA, USA
| | - Robert O. Ritchie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, USA
| | - Mark Asta
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, USA
| | - Andrew M. Minor
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, Berkeley, CA, USA
| |
Collapse
|
2
|
Han Y, Chen H, Sun Y, Liu J, Wei S, Xie B, Zhang Z, Zhu Y, Li M, Yang J, Chen W, Cao P, Yang Y. Ubiquitous short-range order in multi-principal element alloys. Nat Commun 2024; 15:6486. [PMID: 39090088 PMCID: PMC11294451 DOI: 10.1038/s41467-024-49606-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Accepted: 06/06/2024] [Indexed: 08/04/2024] Open
Abstract
Recent research in multi-principal element alloys (MPEAs) has increasingly focused on the role of short-range order (SRO) on material performance. However, the mechanisms of SRO formation and its precise control remain elusive, limiting the progress of SRO engineering. Here, leveraging advanced additive manufacturing techniques that produce samples with a wide range of cooling rates (up to 107 K s-1) and an enhanced semi-quantitative electron microscopy method, we characterize SRO in three CoCrNi-based face-centered-cubic (FCC) MPEAs. Surprisingly, irrespective of the processing and thermal treatment history, all samples exhibit similar levels of SRO. Atomistic simulations reveal that during solidification, prevalent local chemical order arises in the liquid-solid interface (solidification front) even under the extreme cooling rate of 1011 K s-1. This phenomenon stems from the swift atomic diffusion in the supercooled liquid, which matches or even surpasses the rate of solidification. Therefore, SRO is an inherent characteristic of most FCC MPEAs, insensitive to variations in cooling rates and even annealing treatments typically available in experiments.
Collapse
Affiliation(s)
- Ying Han
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Hangman Chen
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA, USA
| | - Yongwen Sun
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Jian Liu
- Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, MA, USA
| | - Shaolou Wei
- Department of Materials Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
- Max-Planck-Institut für Eisenforschung, Düsseldorf, Germany
| | - Bijun Xie
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA, USA
| | - Zhiyu Zhang
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Yingxin Zhu
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Meng Li
- Department of Petroleum and Chemical Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - Judith Yang
- Department of Petroleum and Chemical Engineering, University of Pittsburgh, Pittsburgh, PA, USA
- Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, NY, USA
| | - Wen Chen
- Department of Mechanical and Industrial Engineering, University of Massachusetts, Amherst, MA, USA
| | - Penghui Cao
- Department of Mechanical and Aerospace Engineering, University of California, Irvine, CA, USA.
| | - Yang Yang
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA.
| |
Collapse
|
3
|
Vermale A, Khelladi L, Rojas-Nunez J, Baltazar S, Rogan J, Ramirez M, Roco F, Valencia FJ. Atomistic study of CoCrCuFeNi high entropy alloy nanoparticles: Role of chemical complexity. J Mol Graph Model 2024; 130:108776. [PMID: 38678645 DOI: 10.1016/j.jmgm.2024.108776] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2023] [Revised: 04/09/2024] [Accepted: 04/15/2024] [Indexed: 05/01/2024]
Abstract
High entropy alloy nanoparticles are envisaged as one of the most interesting materials compared to monoatomic materials due to their modulated properties in terms of their convenient surface-to-volume ratio. However, studies are still missing to unveil how composition or nanoparticle size can influence nanoparticle morphology. Based on molecular dynamics simulations, we perform a structural characterization as a function of nanoparticle size and the chemical composition of high entropy alloy nanoparticles subject to multiple annealing cycles. After the multiple thermal loads, we observe a substantial migration of copper atoms towards the np surface, consistent with the experimental results of Cu-based high entropy alloys. The resulting high entropy alloy nanoparticle behaves as a core-shell nanostructure with a rich fcc phase on the surface (50% of Cu) and 5% fcc phase in the nanoparticle core. Inspecting the nanoparticle surface, it is observed that high entropy alloy nanoparticles have a lack of surface facets, leading to a more spherical shape, quite different from mono-metallic nanoparticles with a high number of facets. Performing an average atoms simulation, it showed that nanoparticles are prone to form 111 surface facets independent of the nanoparticle size, suggesting that for high entropy alloy nanoparticles, the chemical complexity avoids the formation of surface facets. The latter can be explained in terms of the lattice distortion inducing tensile/compressive stress that drives the surface reconstruction. All in all our results match extremely well with experimental evidence of FeNiCrCoCu nanocrystalline materials, explaining the Cu segregation in terms of surface energy and mixing enthalpy criteria. We believe that our results provide a detailed characterization of high entropy nanoparticles focusing on how chemical complexity induces morphological changes compared to mono-crystalline nanoparticles. Besides, our findings are valuable for experimental works aimed at designing the shape and composition of multicomponent nanoparticles.
Collapse
Affiliation(s)
- Alice Vermale
- Polytech Clermont, Institut National Polytechnique Clermont Auvergne, 63100, France
| | - Lilian Khelladi
- Polytech Clermont, Institut National Polytechnique Clermont Auvergne, 63100, France
| | - Javier Rojas-Nunez
- Departamento de Física, Universidad de Santiago de Chile, Chile; Centro para el desarrollo de la Nanociencia y Nanotecnología, CEDENNA, Chile
| | - Samuel Baltazar
- Departamento de Física, Universidad de Santiago de Chile, Chile; Centro para el desarrollo de la Nanociencia y Nanotecnología, CEDENNA, Chile
| | - José Rogan
- Centro para el desarrollo de la Nanociencia y Nanotecnología, CEDENNA, Chile; Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, 7800024, Chile
| | - Max Ramirez
- Centro para el desarrollo de la Nanociencia y Nanotecnología, CEDENNA, Chile; Departamento de Física, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago, 7800024, Chile
| | - Fiorella Roco
- Departamento de Computación e Industria, Facultad de Ciencias de la Ingeniería, Universidad Católica del Maule, Talca, Chile
| | - Felipe J Valencia
- Centro para el desarrollo de la Nanociencia y Nanotecnología, CEDENNA, Chile; Departamento de Computación e Industria, Facultad de Ciencias de la Ingeniería, Universidad Católica del Maule, Talca, Chile.
| |
Collapse
|
4
|
Yeh CH, Hsu WD, Liu BH, Yang CS, Kuan CY, Chang YC, Huang KS, Jhang SS, Lu CY, Liaw PK, Shih CF. Low-frequency conductivity of low wear high-entropy alloys. Nat Commun 2024; 15:4554. [PMID: 38811587 PMCID: PMC11136967 DOI: 10.1038/s41467-024-49035-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 05/17/2024] [Indexed: 05/31/2024] Open
Abstract
High-entropy alloys (HEAs) provide new research avenues for alloy combinations in the periodic table, opening numerous possibilities in novel-alloy applications. However, their electrical characteristics have been relatively underexplored. The challenge in establishing an HEA electrical conductivity model lies in the changes in electronic characteristics caused by lattice distortion and complexity of nanostructures. Here we show a low-frequency electrical conductivity model for the Nb-Mo-Ta-W HEA system. The cocktail effect is found to explain trends in electrical-conductivity changes in HEAs, while the magnitude of the reduction is understood by the calculated plasma frequency, free electron density, and measured relaxation time by terahertz spectroscopy. As a result, the refractory HEA Nb15Mo35Ta15W35 thin film exhibits both high hardness and excellent conductivity. This combination of Nb15Mo35Ta15W35 makes it suitable for applications in atomic force microscopy probe coating, significantly improving their wear resistance and atomic-scale image resolution.
Collapse
Affiliation(s)
- Cheng-Hsien Yeh
- Department of Electrical Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Wen-Dung Hsu
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
- Applied High Entropy Technology (AHET) Center, National Cheng Kung University, Tainan, 70101, Taiwan.
- Program on Semiconductor Packaging and Testing, Academy of Innovative Semiconductor and Sustainable Manufacture, National Cheng Kung University, Tainan, 70101, Taiwan.
| | - Bernard Haochih Liu
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
- Applied High Entropy Technology (AHET) Center, National Cheng Kung University, Tainan, 70101, Taiwan.
| | - Chan-Shan Yang
- Applied High Entropy Technology (AHET) Center, National Cheng Kung University, Tainan, 70101, Taiwan.
- Institute and Undergraduate Program of Electro-Optical Engineering, National Taiwan Normal University, Taipei, 11677, Taiwan.
| | - Chen-Yun Kuan
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Yuan-Chun Chang
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Kai-Sheng Huang
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Song-Syun Jhang
- Department of Materials Science and Engineering, National Cheng Kung University, Tainan, 70101, Taiwan
| | - Chia-Yen Lu
- Institute and Undergraduate Program of Electro-Optical Engineering, National Taiwan Normal University, Taipei, 11677, Taiwan
| | - Peter K Liaw
- Department of Materials Science and Engineering, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Chuan-Feng Shih
- Department of Electrical Engineering, National Cheng Kung University, Tainan, 70101, Taiwan.
- Applied High Entropy Technology (AHET) Center, National Cheng Kung University, Tainan, 70101, Taiwan.
- Program on Semiconductor Packaging and Testing, Academy of Innovative Semiconductor and Sustainable Manufacture, National Cheng Kung University, Tainan, 70101, Taiwan.
| |
Collapse
|
5
|
Khort A, Dahlström A, Roslyakov S, Odnevall I. Smallest unit of maximal entropy as novel experimental criterion for parametric characterization of middle- and high-entropy materials. Phys Chem Chem Phys 2024; 26:11271-11276. [PMID: 38563160 DOI: 10.1039/d4cp00776j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/04/2024]
Abstract
Materials with multiple principal elements (middle- and high-entropy materials), are used in emerging applications in various fields due to their unique properties, driven by configuration entropy. Improved understanding and experimental investigations of the impact of the entropy of mixing on the properties of these materials are of large practical interest. Here we show a simplified limited area calculation approach for assessing the entropy of mixing using a CoCuFeNi model nanoalloy. Based on our calculations we propose a new parametric entropy-based criterion, which defines critical scale parameter transition from the maximal entropy state to the entropy-depleted state of the system. The criterion could be used for generalized mechanistic assessment of the effect of the entropy of mixing on the characteristics of the materials with multiple principal elements and for the development and characterization of existing and new middle- and high-entropy materials with both simple single-, and more complex, multiple-sublattice structures.
Collapse
Affiliation(s)
- Alexander Khort
- KTH Royal Institute of Technology, Stockholm, 10044, Sweden.
| | | | - Sergey Roslyakov
- University of Science and Technology ''MISIS'', Moscow, 119049, Russia
| | - Inger Odnevall
- KTH Royal Institute of Technology, Stockholm, 10044, Sweden.
- AIMES - Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden
- Karolinska Institutet, Department of Neuroscience, Stockholm SE-171 77, Sweden
| |
Collapse
|
6
|
Naghdi A, Domínguez-Gutiérrez FJ, Huo WY, Karimi K, Papanikolaou S. Dynamic Nanoindentation and Short-Range Order in Equiatomic NiCoCr Medium-Entropy Alloy Lead to Novel Density Wave Ordering. PHYSICAL REVIEW LETTERS 2024; 132:116101. [PMID: 38563927 DOI: 10.1103/physrevlett.132.116101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Revised: 12/27/2023] [Accepted: 02/09/2024] [Indexed: 04/04/2024]
Abstract
Chemical short-range order is believed to be a key contributor to the exceptional properties of multicomponent alloys. However, its direct validation and confirmation has been highly elusive in most compounds. Recent studies for equiatomic NiCoCr alloys have shown that thermal treatments (i.e., annealing and aging) may facilitate and manipulate such ordering. In this work, by using molecular simulations, we show that nanomechanical probes, such as nanoindentation, may be utilized toward further manipulation of chemical short-range order, providing explicit validation pathways. By using well established interatomic potentials, we perform hybrid molecular-dynamics-Monte Carlo at room temperature to demonstrate that particular dwell nanoindentation protocols can lead, through thermal Monte Carlo equilibration, to local reorganization under the indenter tip, toward a density-wave stripe pattern. We characterize the novel density-wave structures, which are highly anisotropic and dependent on local, nanoindentation-induced stress concentrations, and we show how they deeply originate from intrinsic features of interelemental interactions. Furthermore, we show that these novel patterns consistently scale with the incipient plastic zone, under the indenter tip, justifying their observation at experimentally feasible nanoindentation depths.
Collapse
Affiliation(s)
- A Naghdi
- NOMATEN Centre of Excellence, National Center for Nuclear Research, ulica A. Sołtana 7, 05-400 Swierk/Otwock, Poland
- IDEAS NCBR, ulica Chmielna 69, 00-801 Warsaw, Poland
| | - F J Domínguez-Gutiérrez
- NOMATEN Centre of Excellence, National Center for Nuclear Research, ulica A. Sołtana 7, 05-400 Swierk/Otwock, Poland
| | - W Y Huo
- NOMATEN Centre of Excellence, National Center for Nuclear Research, ulica A. Sołtana 7, 05-400 Swierk/Otwock, Poland
- College of Mechanical and Electrical Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - K Karimi
- NOMATEN Centre of Excellence, National Center for Nuclear Research, ulica A. Sołtana 7, 05-400 Swierk/Otwock, Poland
| | - S Papanikolaou
- NOMATEN Centre of Excellence, National Center for Nuclear Research, ulica A. Sołtana 7, 05-400 Swierk/Otwock, Poland
| |
Collapse
|
7
|
Yang Y, Yin S, Yu Q, Zhu Y, Ding J, Zhang R, Ophus C, Asta M, Ritchie RO, Minor AM. Rejuvenation as the origin of planar defects in the CrCoNi medium entropy alloy. Nat Commun 2024; 15:1402. [PMID: 38365867 PMCID: PMC10873362 DOI: 10.1038/s41467-024-45696-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 01/30/2024] [Indexed: 02/18/2024] Open
Abstract
High or medium- entropy alloys (HEAs/MEAs) are multi-principal element alloys with equal atomic elemental composition, some of which have shown record-breaking mechanical performance. However, the link between short-range order (SRO) and the exceptional mechanical properties of these alloys has remained elusive. The local destruction of SRO by dislocation glide has been predicted to lead to a rejuvenated state with increased entropy and free energy, creating softer zones within the matrix and planar fault boundaries that enhance the ductility, but this has not been verified. Here, we integrate in situ nanomechanical testing with energy-filtered four-dimensional scanning transmission electron microscopy (4D-STEM) and directly observe the rejuvenation during cyclic mechanical loading in single crystal CrCoNi at room temperature. Surprisingly, stacking faults (SFs) and twin boundaries (TBs) are reversible in initial cycles but become irreversible after a thousand cycles, indicating SF energy reduction and rejuvenation. Molecular dynamics (MD) simulation further reveals that the local breakdown of SRO in the MEA triggers these SF reversibility changes. As a result, the deformation features in HEAs/MEAs remain planar and highly localized to the rejuvenated planes, leading to the superior damage tolerance characteristic in this class of alloys.
Collapse
Affiliation(s)
- Yang Yang
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA.
| | - Sheng Yin
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Qin Yu
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Yingxin Zhu
- Department of Engineering Science and Mechanics and Materials Research Institute, The Pennsylvania State University, University Park, PA, USA
| | - Jun Ding
- Center for Alloy Innovation and Design (CAID), State Key Laboratory for Mechanical Behavior of Materials, Xi'an Jiaotong University, Xi'an, China
| | - Ruopeng Zhang
- Department of Materials Science and Engineering, University of California, Berkeley, CA, USA
| | - Colin Ophus
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Mark Asta
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, CA, USA
| | - Robert O Ritchie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science and Engineering, University of California, Berkeley, CA, USA
| | - Andrew M Minor
- National Center for Electron Microscopy, Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Materials Science and Engineering, University of California, Berkeley, CA, USA.
| |
Collapse
|
8
|
Rasooli N, Chen W, Daly M. Deformation mechanisms in high entropy alloys: a minireview of short-range order effects. NANOSCALE 2024; 16:1650-1663. [PMID: 38180135 DOI: 10.1039/d3nr05251f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
The complex atomic scale structure of high entropy alloys presents new opportunities to expand the deformation theories of mechanical metallurgy. In this regard, solute-defect interactions have emerged as critical piece in elucidating the operation of deformation mechanisms. While notable progress has been made in understanding solute-defect interactions for random solute arrangements, recent interest in high entropy alloys with short-range order adds a new layer of structural complexity for which a cohesive picture has yet to emerge. To this end, this minireview synthesizes the current understanding of short-range order effects on defect behavior through an examination of the key recent literature. This analysis centers on the nanoscale metallurgy of deformation mechanisms, with the order-induced changes to the relevant defect energy landscapes serving as a touchstone for discussion. The topics reviewed include dislocation-mediated strengthening, twinning and phase transformation-based mechanisms, and vacancy-mediated processes. This minireview concludes with remarks on current challenges and opportunities for future efforts.
Collapse
Affiliation(s)
- Novin Rasooli
- Department of Civil, Materials, and Environmental Engineering, University of Illinois Chicago, 842 W. Taylor St, 2095 ERF (MC 246), Chicago, IL, 60607, USA.
| | - Wei Chen
- Department of Mechanical, Materials, and Aerospace Engineering, Illinois Institute of Technology, Chicago, IL 60616, USA
- Department of Materials Design and Innovation, University at Buffalo, The State University of New York, Buffalo, NY 14260, USA.
| | - Matthew Daly
- Department of Civil, Materials, and Environmental Engineering, University of Illinois Chicago, 842 W. Taylor St, 2095 ERF (MC 246), Chicago, IL, 60607, USA.
| |
Collapse
|
9
|
Huang Z, Li T, Li B, Dong Q, Smith J, Li S, Xu L, Wang G, Chi M, Hu L. Tailoring Local Chemical Ordering via Elemental Tuning in High-Entropy Alloys. J Am Chem Soc 2024; 146:2167-2173. [PMID: 38214166 DOI: 10.1021/jacs.3c12048] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2024]
Abstract
Due to the large multi-elemental space desired for property screening and optimization, high-entropy alloys (HEAs) hold greater potential over conventional alloys for a range of applications, such as structural materials, energy conversion, and catalysis. However, the relationship between the HEA composition and its local structural/elemental configuration is not well understood, particularly in noble-metal-based HEA nanomaterials, hindering the design and development of nano-HEAs in energy conversion and catalysis applications. Herein, we determined precise atomic-level structural and elemental arrangements in model HEAs composed of RhPtPdFeCo and RuPtPdFeCo to unveil their local characteristics. Notably, by changing just one constituent element in the HEA (Rh to Ru), we found dramatic changes in the elemental arrangement from complete random mixing to a local single elemental ordering feature. Additionally, we demonstrate that the local ordering in RuPtPdFeCo can be further controlled by varying the Ru concentration, allowing us to toggle between local Ru clustering and distinct heterostructures in multicomponent systems. Overall, our study presents a practical approach for manipulating local atomic structures and elemental arrangements in noble-metal-based HEA systems, which could provide in-depth knowledge to mechanistically understand the functionality of noble-metal-based HEA nanomaterials in practical applications.
Collapse
Affiliation(s)
- Zhennan Huang
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Tangyuan Li
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Boyang Li
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Qi Dong
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Jacob Smith
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Shuke Li
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Lin Xu
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| | - Guofeng Wang
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261, United States
| | - Miaofang Chi
- Center for Nanophase Materials Science, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Liangbing Hu
- Department of Materials Science and Engineering, University of Maryland, College Park, Maryland 20742, United States
| |
Collapse
|
10
|
Gao H, Guo N, Gong Y, Bai L, Wang D, Zheng Q. Sub-Ångstrom-scale structural variations in high-entropy oxides. NANOSCALE 2023. [PMID: 37987086 DOI: 10.1039/d3nr05176e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
High-entropy oxides (HEOs) are a special class of materials that utilize the concept of high-entropy alloys (HEAs) with five or more elements randomly distributing at a single sublattice in near-equiatomic proportions. HEOs have been attracting increasing attention owing to their many outstanding physical and chemical properties. However, unlike HEAs, for which local chemical compositions, order/disorder behaviors, and property-structure relationships have been comprehensively investigated, detailed information on the atomic-scale chemical and structural features and their correlations with functionalities in HEOs so far is still not sufficient. Herein, we select four typical HEOs with pyrochlore, spinel, perovskite and rock-salt type structures, and directly observe and quantify sub-Ångstrom-scale structure variations in different manners by means of advanced aberration-corrected scanning transmission electron microscopy techniques. Visualization and quantification of local structural variations and lattice distortions in the current work may show a valuable example for future investigations on local fluctuating structures and their relationships with properties in more systems of HEOs.
Collapse
Affiliation(s)
- Hanbin Gao
- Henan Institute of Advanced Technology, Zhengzhou University, Zhengzhou 450003, China
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
| | - Ning Guo
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Yue Gong
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 101408, China
| | - Lu Bai
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
| | - Dongwei Wang
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
| | - Qiang Zheng
- CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing 100190, China.
- University of Chinese Academy of Sciences, Beijing 101408, China
| |
Collapse
|
11
|
Wu Y, Shao J. Unraveling Anisotropy in Crystalline Orientation under Shock-Induced Dynamic Responses in High-Entropy Alloy Co 25Ni 25Fe 25Al 7.5Cu 17.5. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:2446. [PMID: 37686954 PMCID: PMC10490121 DOI: 10.3390/nano13172446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 08/21/2023] [Accepted: 08/28/2023] [Indexed: 09/10/2023]
Abstract
Shock-induced plastic deformation and spall damage in the single-crystalline FCC Co25Ni25Fe25Al7.5Cu17.5 high-entropy alloy (HEA) under varying shock intensities were systematically investigated using large-scale molecular dynamics simulations. The study reveals the significant influence of crystalline orientation on the deformation mechanism and spall damage. Specifically, the shock wave velocities in the [110] and [111] directions are significantly higher than that in the [001] direction, resulting in a two-zone elastic-plastic shock wave structure observed in the [110] and [111] samples, while only a single-wave structure is found in the [001] sample. The plastic deformation is dominated by the FCC to BCC transformation following the Bain path and a small amount of stacking faults during the compression stage in the [001] sample, whereas it depends on the stacking faults induced by Shockley dislocation motion in the [110] and [111] samples. The stacking faults and phase transformation in the [001] sample exhibit high reversibility under release effects, while extensive dislocations are present in the [110] and [111] samples after release. Interestingly, tension-strain-induced FCC to BCC phase transformation is observed in the [001] sample during the release stage, resulting in increased spall strength compared to the [110] and [111] samples. The spall strength estimated from both bulk and free surface velocity history shows reasonable consistency. Additionally, the spall strength remains stable with increasing shock intensities. The study discusses in detail the shock wave propagation, microstructure change, and spall damage evolution. Overall, our comprehensive studies provide deep insights into the deformation and fracture mechanisms of Co25Ni25Fe25Al7.5Cu17.5 HEA under shock loading, contributing to a better understanding of dynamic deformation under extreme environments.
Collapse
Affiliation(s)
- Yongchao Wu
- State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China;
| | - Jianli Shao
- State Key Laboratory of Explosion Science and Technology, Beijing Institute of Technology, Beijing 100081, China;
- Explosion Protection and Emergency Disposal Technology Engineering Research Center of the Ministry of Education, Beijing 100039, China
| |
Collapse
|
12
|
Walsh F, Zhang M, Ritchie RO, Minor AM, Asta M. Extra electron reflections in concentrated alloys do not necessitate short-range order. NATURE MATERIALS 2023; 22:926-929. [PMID: 37524815 DOI: 10.1038/s41563-023-01570-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/02/2023]
Affiliation(s)
- Flynn Walsh
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Graduate Group in Applied Science & Technology, University of California, Berkeley, CA, USA
| | - Mingwei Zhang
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science & Engineering, University of California, Berkeley, CA, USA
| | - Robert O Ritchie
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science & Engineering, University of California, Berkeley, CA, USA
| | - Andrew M Minor
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- National Center for Electron Microscopy, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Materials Science & Engineering, University of California, Berkeley, CA, USA
| | - Mark Asta
- Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
- Department of Materials Science & Engineering, University of California, Berkeley, CA, USA.
| |
Collapse
|