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Huang Y, Nie J, Bai W, Hu S, Wang X, Zhang L, Liu L. Diffusivities and Atomic Mobilities in BCC Ti-Fe-Cr Alloys. MATERIALS (BASEL, SWITZERLAND) 2024; 17:1927. [PMID: 38673284 PMCID: PMC11051987 DOI: 10.3390/ma17081927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 04/12/2024] [Accepted: 04/15/2024] [Indexed: 04/28/2024]
Abstract
In this research, the diffusion behaviors within the Ti-Fe-Cr ternary system were examined at the temperatures of 1273 K and 1373 K through the diffusion couple technique. This study led to the determination of both ternary inter-diffusion and impurity diffusion coefficients in the body-centered cubic (bcc) phase for the Ti-Fe-Cr alloy, utilizing the Whittle-Green and Hall methods. The statistics show that the average diffusion coefficients D˜FeFeTi and D˜CrCrTi measured at 1273 K were 1.34 × 10-12 and 3.66 × 10-13, respectively. At 1373 K, the average values of D˜FeFeTi and D˜CrCrTi were 4.89 × 10-12 and 1.43 × 10-12. By adopting the CALPHAD method, a self-consistent database for atomic mobility in the bcc phase of the Ti-Fe-Cr system was established. This database underwent refinement by comparing the newly acquired diffusion coefficients with data from the existing literature. Diffusion simulations for the diffusion couples were performed, drawing on the established database. The error between the simulated diffusion coefficient and the experimental measurement data is within 15%, and the simulated data of the component distance distribution and diffusion path are in good agreement with the experimental data. The simulations generated results that aligned well with the observed experimental diffusion characteristics, thereby affirming the reliability and accuracy of the database.
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Affiliation(s)
- Yi Huang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; (Y.H.); (J.N.); (S.H.); (X.W.)
- Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan 411105, China
| | - Jingjing Nie
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; (Y.H.); (J.N.); (S.H.); (X.W.)
- Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan 411105, China
| | - Weimin Bai
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; (Y.H.); (J.N.); (S.H.); (X.W.)
- Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan 411105, China
| | - Songsong Hu
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; (Y.H.); (J.N.); (S.H.); (X.W.)
- Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan 411105, China
| | - Xinming Wang
- School of Materials Science and Engineering, Xiangtan University, Xiangtan 411105, China; (Y.H.); (J.N.); (S.H.); (X.W.)
- Key Laboratory of Materials Design and Preparation Technology of Hunan Province, Xiangtan University, Xiangtan 411105, China
| | - Ligang Zhang
- School of Materials Science and Engineering, Central South University, Changsha 410083, China;
| | - Libin Liu
- School of Materials Science and Engineering, Central South University, Changsha 410083, China;
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Li MG, Hu M, Fan LM, Bao JD, Li PC. Quantifying the energy landscape in weakly and strongly disordered frictional media. J Chem Phys 2024; 160:024903. [PMID: 38189619 DOI: 10.1063/5.0178092] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2023] [Accepted: 12/19/2023] [Indexed: 01/09/2024] Open
Abstract
We investigate the "roughness" of the energy landscape of a system that diffuses in a heterogeneous medium with a random position-dependent friction coefficient α(x). This random friction acting on the system stems from spatial inhomogeneity in the surrounding medium and is modeled using the generalized Caldira-Leggett model. For a weakly disordered medium exhibiting a Gaussian random diffusivity D(x) = kBT/α(x) characterized by its average value ⟨D(x)⟩ and a pair-correlation function ⟨D(x1)D(x2)⟩, we find that the renormalized intrinsic diffusion coefficient is lower than the average one due to the fluctuations in diffusivity. The induced weak internal friction leads to increased roughness in the energy landscape. When applying this idea to diffusive motion in liquid water, the dissociation energy for a hydrogen bond gradually approaches experimental findings as fluctuation parameters increase. Conversely, for a strongly disordered medium (i.e., ultrafast-folding proteins), the energy landscape ranges from a few to a few kcal/mol, depending on the strength of the disorder. By fitting protein folding dynamics to the escape process from a metastable potential, the decreased escape rate conceptualizes the role of strong internal friction. Studying the energy landscape in complex systems is helpful because it has implications for the dynamics of biological, soft, and active matter systems.
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Affiliation(s)
- Ming-Gen Li
- Department of Physics, Shantou University, Shantou, Guangdong 515063, China
| | - Meng Hu
- Department of Mathematics and Physics, North China Electric Power University, Baoding 071003, China
| | - Li-Ming Fan
- College of Physical Science and Technology, Shenyang Normal University, Shenyang 110034, China
| | - Jing-Dong Bao
- Department of Physics, Beijing Normal University, Beijing 100048, China
| | - Peng-Cheng Li
- Department of Physics, Shantou University, Shantou, Guangdong 515063, China
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