1
|
He H, Naeem M, Zhang F, Zhao Y, Harjo S, Kawasaki T, Wang B, Wu X, Lan S, Wu Z, Yin W, Wu Y, Lu Z, Kai JJ, Liu CT, Wang XL. Stacking Fault Driven Phase Transformation in CrCoNi Medium Entropy Alloy. Nano Lett 2021; 21:1419-1426. [PMID: 33464087 DOI: 10.1021/acs.nanolett.0c04244] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Phase transformation is an effective means to increase the ductility of a material. However, even for a commonly observed face-centered-cubic to hexagonal-close-packed (fcc-to-hcp) phase transformation, the underlying mechanisms are far from being settled. In fact, different transformation pathways have been proposed, especially with regard to nucleation of the hcp phase at the nanoscale. In CrCoNi, a so-called medium-entropy alloy, an fcc-to-hcp phase transformation has long been anticipated. Here, we report an in situ loading study with neutron diffraction, which revealed a bulk fcc-to-hcp phase transformation in CrCoNi at 15 K under tensile loading. By correlating deformation characteristics of the fcc phase with the development of the hcp phase, it is shown that the nucleation of the hcp phase was triggered by intrinsic stacking faults. The confirmation of a bulk phase transformation adds to the myriads of deformation mechanisms available in CrCoNi, which together underpin the unusually large ductility at low temperatures.
Collapse
Affiliation(s)
- Haiyan He
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen Hi-Tech Industrial Park, Shenzhen, Guangdong 518057, China
| | - Muhammad Naeem
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen Hi-Tech Industrial Park, Shenzhen, Guangdong 518057, China
| | - Fan Zhang
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Yilu Zhao
- Department of Mechanical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Stefanus Harjo
- J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Takuro Kawasaki
- J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Bing Wang
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Xuelian Wu
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Si Lan
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China
| | - Zhenduo Wu
- Center for Neutron Scattering, City University of Hong Kong Dongguan Research Institute Song Shan Lake, Dongguan 523000, China
| | - Wen Yin
- China Spallation Neutron Source, Institute of High Energy Physics, Chinese Academy of Sciences, Dongguan 523000, China
| | - Yuan Wu
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhaoping Lu
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Ji-Jung Kai
- Department of Mechanical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Chain-Tsuan Liu
- Department of Mechanical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- Department of Materials Science and Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
| | - Xun-Li Wang
- Department of Physics, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, China
- City University of Hong Kong Shenzhen Research Institute, Shenzhen Hi-Tech Industrial Park, Shenzhen, Guangdong 518057, China
| |
Collapse
|
2
|
Hu C, Somani M, Misra R, Yang C. The significance of phase reversion-induced nanograined/ultrafine-grained structure on the load-controlled deformation response and related mechanism in copper-bearing austenitic stainless steel. J Mech Behav Biomed Mater 2020; 104:103666. [DOI: 10.1016/j.jmbbm.2020.103666] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2019] [Revised: 01/24/2020] [Accepted: 01/30/2020] [Indexed: 12/22/2022]
|
3
|
Naeem M, He H, Zhang F, Huang H, Harjo S, Kawasaki T, Wang B, Lan S, Wu Z, Wang F, Wu Y, Lu Z, Zhang Z, Liu CT, Wang XL. Cooperative deformation in high-entropy alloys at ultralow temperatures. Sci Adv 2020; 6:eaax4002. [PMID: 32258390 PMCID: PMC7101227 DOI: 10.1126/sciadv.aax4002] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 01/03/2020] [Indexed: 05/20/2023]
Abstract
High-entropy alloys exhibit exceptional mechanical properties at cryogenic temperatures, due to the activation of twinning in addition to dislocation slip. The coexistence of multiple deformation pathways raises an important question regarding how individual deformation mechanisms compete or synergize during plastic deformation. Using in situ neutron diffraction, we demonstrate the interaction of a rich variety of deformation mechanisms in high-entropy alloys at 15 K, which began with dislocation slip, followed by stacking faults and twinning, before transitioning to inhomogeneous deformation by serrations. Quantitative analysis showed that the cooperation of these different deformation mechanisms led to extreme work hardening. The low stacking fault energy plus the stable face-centered cubic structure at ultralow temperatures, enabled by the high-entropy alloying, played a pivotal role bridging dislocation slip and serration. Insights from the in situ experiments point to the role of entropy in the design of structural materials with superior properties.
Collapse
Affiliation(s)
- Muhammad Naeem
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Haiyan He
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Fan Zhang
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Hailong Huang
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Stefanus Harjo
- J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Takuro Kawasaki
- J-PARC Center, Japan Atomic Energy Agency, Tokai, Ibaraki 319-1195, Japan
| | - Bing Wang
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Si Lan
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
- Herbert Gleiter Institute of Nanoscience, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China
| | - Zhenduo Wu
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Feng Wang
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Yuan Wu
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhaoping Lu
- State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing 100083, China
| | - Zhongwu Zhang
- Institute for Metallic Materials, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, China
| | - Chain T. Liu
- Department of Materials Science and Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
- Department of Mechanical Engineering, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
| | - Xun-Li Wang
- Department of Physics, City University of Hong Kong, 83 Tat Chee Avenue, Kowloon, Hong Kong
- City University of Hong Kong Shenzhen Research Institute, 8 Yuexing 1st Road, Shenzhen Hi-Tech Industrial Park, Shenzhen 518057, China
- Corresponding author.
| |
Collapse
|
4
|
Zhou X, Li X, Lu K. Size Dependence of Grain Boundary Migration in Metals under Mechanical Loading. Phys Rev Lett 2019; 122:126101. [PMID: 30978032 DOI: 10.1103/physrevlett.122.126101] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2018] [Revised: 01/23/2019] [Indexed: 06/09/2023]
Abstract
The greatly increased grain boundary (GB) mobility in nanograined metals under mechanical loading is distinguished from that in their coarse-grained counterparts. The feature leads to softening of nanograined materials and deviation of strength from the classical Hall-Petch relationship. In this Letter, grain size dependences of GB migration in nanograined Ag, Cu, and Ni under tension were investigated quantitatively in a wide size range. As grain size decreases from submicron, GB migration intensifies and then diminishes below a critical grain size. The GB migration peaks at about 80, 75, and 38 nm in Ag, Cu, and Ni, respectively. The suppression of GB migration below a critical size can be attributed to GB relaxation during sample processing or by postthermal annealing. With relaxed GBs the governing deformation mechanism of nanograins shifts from GB migration to formation of through-grain twins or stacking faults. GB relaxation, analogous to GB segregation, offers a novel approach to stabilizing nanograined materials under mechanical loading.
Collapse
Affiliation(s)
- Xin Zhou
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China
- School of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Xiuyan Li
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China
| | - K Lu
- Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016, China
| |
Collapse
|
5
|
Louhichi A, Tamborini E, Oberdisse J, Cipelletti L, Ramos L. Viscoelasticity of colloidal polycrystals doped with impurities. Phys Rev E Stat Nonlin Soft Matter Phys 2015; 92:032307. [PMID: 26465473 DOI: 10.1103/physreve.92.032307] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Indexed: 06/05/2023]
Abstract
We investigate how the microstructure of a colloidal polycrystal influences its linear visco-elasticity. We use thermosensitive copolymer micelles that arrange in water in a cubic crystalline lattice, yielding a colloidal polycrystal. The polycrystal is doped with a small amount of nanoparticles, of size comparable to that of the micelles, which behave as impurities and thus partially segregate in the grain boundaries. We show that the shear elastic modulus only depends on the packing of the micelles and varies neither with the presence of nanoparticles nor with the crystal microstructure. By contrast, we find that the loss modulus is strongly affected by the presence of nanoparticles. A comparison between rheology data and small-angle neutron-scattering data suggests that the loss modulus is dictated by the total amount of nanoparticles in the grain boundaries, which in turn depends on the sample microstructure.
Collapse
Affiliation(s)
- Ameur Louhichi
- Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, Montpellier F-34095, France
| | - Elisa Tamborini
- Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, Montpellier F-34095, France
| | - Julian Oberdisse
- Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, Montpellier F-34095, France
| | - Luca Cipelletti
- Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, Montpellier F-34095, France
| | - Laurence Ramos
- Laboratoire Charles Coulomb (L2C), UMR 5221 CNRS-Université de Montpellier, Montpellier F-34095, France
| |
Collapse
|
6
|
Abstract
We use confocal microscopy and time-resolved light scattering to investigate plasticity in a colloidal polycrystal, following the evolution of the network of grain boundaries as the sample is submitted to thousands of shear deformation cycles. The grain boundary motion is found to be ballistic, with a velocity distribution function exhibiting nontrivial power law tails. The shear-induced dynamics initially slow down, similarly to the aging of the spontaneous dynamics in glassy materials, but eventually reach a steady state. Surprisingly, the crossover time between the initial aging regime and the steady state decreases with increasing probed length scale, hinting at a hierarchical organization of the grain boundary dynamics.
Collapse
Affiliation(s)
- Elisa Tamborini
- Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France
| | - Luca Cipelletti
- Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France
| | - Laurence Ramos
- Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France and CNRS, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France
| |
Collapse
|
7
|
Abstract
A new physical mechanism of plastic flow in solids is suggested and theoretically described. The mechanism represents stress-driven rotations of grain boundaries (GBs) in subsurface areas of solids. The stress and energy characteristics of the GB rotations are calculated. In the case of nickel, we find that such rotations are energetically favorable processes in a wide range of GB parameters. Our theory is consistent with the experimental observation [D. Jang and J. R. Greer, Scr. Mater. 64, 77 (2011).] of GB rotations in deformed nanocrystalline nickel nanopillars.
Collapse
Affiliation(s)
- S V Bobylev
- Institute of Problems of Mechanical Engineering, Russian Academy of Sciences, Bolshoj 61, Vasilievskii Ostrov, St. Petersburg 199178, Russia
| | | |
Collapse
|
8
|
Hofmann F, Song X, Abbey B, Jun TS, Korsunsky AM. High-energy transmission Laue micro-beam X-ray diffraction: a probe for intra-granular lattice orientation and elastic strain in thicker samples. J Synchrotron Radiat 2012; 19:307-318. [PMID: 22514163 DOI: 10.1107/s0909049512003044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/09/2011] [Accepted: 01/24/2012] [Indexed: 05/31/2023]
Abstract
An understanding of the mechanical response of modern engineering alloys to complex loading conditions is essential for the design of load-bearing components in high-performance safety-critical aerospace applications. A detailed knowledge of how material behaviour is modified by fatigue and the ability to predict failure reliably are vital for enhanced component performance. Unlike macroscopic bulk properties (e.g. stiffness, yield stress, etc.) that depend on the average behaviour of many grains, material failure is governed by `weakest link'-type mechanisms. It is strongly dependent on the anisotropic single-crystal elastic-plastic behaviour, local morphology and microstructure, and grain-to-grain interactions. For the development and validation of models that capture these complex phenomena, the ability to probe deformation behaviour at the micro-scale is key. The diffraction of highly penetrating synchrotron X-rays is well suited to this purpose and micro-beam Laue diffraction is a particularly powerful tool that has emerged in recent years. Typically it uses photon energies of 5-25 keV, limiting penetration into the material, so that only thin samples or near-surface regions can be studied. In this paper the development of high-energy transmission Laue (HETL) micro-beam X-ray diffraction is described, extending the micro-beam Laue technique to significantly higher photon energies (50-150 keV). It allows the probing of thicker sample sections, with the potential for grain-level characterization of real engineering components. The new HETL technique is used to study the deformation behaviour of individual grains in a large-grained polycrystalline nickel sample during in situ tensile loading. Refinement of the Laue diffraction patterns yields lattice orientations and qualitative information about elastic strains. After deformation, bands of high lattice misorientation can be identified in the sample. Orientation spread within individual scattering volumes is studied using a pattern-matching approach. The results highlight the inability of a simple Schmid-factor model to capture the behaviour of individual grains and illustrate the need for complementary mechanical modelling.
Collapse
Affiliation(s)
- Felix Hofmann
- Chemistry Department, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139-4307, USA.
| | | | | | | | | |
Collapse
|
9
|
Wang YM, Ott RT, Hamza AV, Besser MF, Almer J, Kramer MJ. Achieving large uniform tensile ductility in nanocrystalline metals. Phys Rev Lett 2010; 105:215502. [PMID: 21231320 DOI: 10.1103/physrevlett.105.215502] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/20/2010] [Indexed: 05/30/2023]
Abstract
Synchrotron x-ray diffraction and high-resolution electron microscopy revealed the origin of different strain hardening behaviors (and dissimilar tensile ductility) in nanocrystalline Ni and nanocrystalline Co. Planar defect accumulations and texture evolution were observed in Co but not in Ni, suggesting that interfacial defects are an effective passage to promote strain hardening in truly nanograins. Twinning becomes less significant in Co when grain sizes reduce to below ~15 nm. This study offers insights into achieving excellent mechanical properties in nanocrystalline materials.
Collapse
Affiliation(s)
- Y M Wang
- Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
| | | | | | | | | | | |
Collapse
|
10
|
Cheng S, Zhao Y, Wang Y, Li Y, Wang XL, Liaw PK, Lavernia EJ. Structure modulation driven by cyclic deformation in nanocrystalline NiFe. Phys Rev Lett 2010; 104:255501. [PMID: 20867394 DOI: 10.1103/physrevlett.104.255501] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2010] [Indexed: 05/29/2023]
Abstract
Theoretical modeling suggests that the grain size remains unchanged during fatigue crack growth in nanocrystalline metals. Here we demonstrate that a modulated structure is generated in a nanocrystalline Ni-Fe alloy under cyclic deformation. Substantial grain coarsening and loss of growth twins are observed in the path of fatigue cracks, while the grains away from the cracks remain largely unaffected. Statistical analyses suggest that the grain coarsening is realized through the grain lattice rotation and coalescence and the loss of growth twins may be related to the detwinning process near crack tip.
Collapse
Affiliation(s)
- Sheng Cheng
- Department of Materials Science and Engineering, The University of Tennessee, Knoxville, Tennessee 37996, USA.
| | | | | | | | | | | | | |
Collapse
|
11
|
Abstract
Low strain hardening has hitherto been considered an intrinsic behavior for most nanocrystalline (NC) metals, due to their perceived inability to accumulate dislocations. In this Letter, we show strong strain hardening in NC nickel with a grain size of approximately 20 nm under large plastic strains. Contrary to common belief, we have observed significant dislocation accumulation in the grain interior. This is enabled primarily by Lomer-Cottrell locks, which pin the lock-forming dislocations and obstruct dislocation motion. These observations may help with developing strong and ductile NC metals and alloys.
Collapse
Affiliation(s)
- X L Wu
- State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
| | | | | | | |
Collapse
|