Article
Materials Science, Multidisciplinary
Jingliang Wang, Masato Enomoto, Chengjia Shang
Summary: First-principles calculations were conducted to investigate the Sigma 5(310) grain boundary in Fe with B, C, and P, revealing the embrittlement caused by P and the de-embrittling effect of B and C. The energetic preference of interstitial B and C over interstitial P was found, with only substitutional P exacerbating grain boundary cohesion. The study demonstrated that the influence of these elements on the grain boundary cohesion is a complex interplay between mechanical and chemical contributions.
Article
Materials Science, Multidisciplinary
Kazuma Ito, Yuta Tanaka, Kazumasa Tsutsui, Tomohiko Omura
Summary: The development of high-strength steels is essential for achieving a decarbonized society. The addition of molybdenum (Mo) has been proven effective in addressing the problem of hydrogen embrittlement, but its underlying mechanism remains unclear. In this study, a calculation method was developed to evaluate the impact of adding alloying elements on the grain boundary segregation of hydrogen (H) using first-principles calculations. The results showed that a small amount of Mo segregates to α-Fe grain boundaries and reduces the grain boundary H concentration due to repulsive interactions between Mo and H. This information can contribute to the development of high-strength steels with excellent resistance to hydrogen embrittlement.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Nanoscience & Nanotechnology
Kazuho Okada, Akinobu Shibata, Taisuke Sasaki, Hisashi Matsumiya, Kazuhiro Hono, Nobuhiro Tsuji
Summary: This study aimed to improve the resistance against hydrogen embrittlement by increasing the concentration of carbon segregated at prior austenite grain boundary (PAGB), XPAGB, in low-carbon martensitic steels. The specimens with and without carbon segregation treatment (Non-seg and Seg specimens, respectively) had similar microstructures, except for higher XPAGB in the Seg specimen. The Seg specimen exhibited higher maximum stress and smaller fraction of intergranular fracture surface under hydrogen-charged conditions, indicating that segregated carbon suppressed hydrogen accumulation and increased cohesive energy of PAGB.
SCRIPTA MATERIALIA
(2023)
Article
Nanoscience & Nanotechnology
Heena Khanchandani, Baptiste Gault
Summary: High strength twinning induced plasticity (TWIP) steels have potential for applications in the automotive industry, but they are susceptible to hydrogen embrittlement (HE) and galvanic corrosion. This study investigates the susceptibility towards HE and oxidation of a model Fe 27Mn 0.3C (wt%) TWIP steel using atom probe tomography. The segregation of hydrogen and oxygen at grain boundaries, correlated with manganese depletion, is measured. The study suggests a correlation between HE and oxidation mechanisms in TWIP steels, which can contribute to hydrogen enhanced decohesion of grain boundaries.
SCRIPTA MATERIALIA
(2023)
Article
Nuclear Science & Technology
Elin Toijer, Par A. T. Olsson, Par Olsson
Summary: This study investigates the impact of phosphorus impurities on the grain boundary strength of nickel using Density Functional Theory (DFT) modeling. Three different DFT based methods were employed, showing varying results on whether phosphorus strengthens or weakens the nickel grain boundary. The discrepancies in results are attributed to the applied model, partition scheme and interpretation of outcomes, emphasizing the importance of accurately describing the fracture process.
NUCLEAR MATERIALS AND ENERGY
(2021)
Article
Materials Science, Multidisciplinary
Man Long, Zhengjun Yao, Wenbo Du, Changqing Shu, Xiangshan Kong, Shasha Zhang
Summary: This research focuses on the co-segregation behavior of solute atoms and hydrogen atoms at specific grain boundaries in aluminum alloys. The study reveals that the co-segregation energy is influenced by the segregation behaviors of solute atoms and their interactions with hydrogen atoms. The interactions between different solute atoms are influenced by elastic and charge interactions.
COMPUTATIONAL MATERIALS SCIENCE
(2024)
Article
Materials Science, Multidisciplinary
X. H. Chen, X. Q. Zhuang, J. W. Mo, J. Y. He, T. Yang, X. Y. Zhou, W. H. Liu
Summary: The study demonstrates that boron doping can effectively reduce the ductility loss and enhance the resistance to hydrogen embrittlement in CrCoNi medium-entropy alloy, by improving grain-boundary cohesion and reducing hydrogen diffusivity.
MATERIALS RESEARCH LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Boning Zhang, Kai Xiong, Maoqiu Wang, Zhenbao Liu, Kun Shen, Yong Mao, Hao Chen
Summary: This study investigates solute-hydrogen interactions at different grain boundaries using first-principles calculations, and identifies effective descriptors for grain boundary engineering strategies, providing fundamental insights for designing high-performance alloys resistant to hydrogen embrittlement.
SCRIPTA MATERIALIA
(2024)
Article
Chemistry, Multidisciplinary
Ali Ahmadian, Daniel Scheiber, Xuyang Zhou, Baptiste Gault, Lorenz Romaner, Reza D. Kamachali, Werner Ecker, Gerhard Dehm, Christian H. Liebscher
Summary: The embrittlement of metallic alloys by liquid metals is a serious problem that affects their structural integrity. This study reveals how boron segregation can mitigate the detrimental effects of zinc, a prime embrittler, in a specific type of grain boundary in alpha-Fe (4 at.% Al). Zinc induces nanoscale segregation patterns that result in complex grain boundary states. Ab initio simulations show that boron inhibits zinc segregation and compensates for the loss of grain boundary cohesion caused by zinc. This research sheds new light on how interstitial solutes can modify grain boundaries and suggests their potential use as dopants to prevent material failure.
ADVANCED MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Ge Zhang, Guoqing Chen, Chinnapat Panwisawas, Xinyan Teng, Yaorui Ma, Rong An, Yongxian Huang, Jian Cao, Xuesong Leng
Summary: This study systematically investigates the effect of oxygen segregation on the embrittlement of molybdenum grain boundaries. It is found that oxygen segregation weakens the grain boundary cohesion and increases the intergranular cleavage tendency of molybdenum. However, oxygen segregation does not always trigger grain boundary embrittlement under certain conditions.
Article
Materials Science, Multidisciplinary
M. C. Niu, C. J. Chen, W. Li, K. Yang, J. H. Luan, W. Wang, Z. B. Jiao
Summary: Understanding the solute interaction effects on grain boundary segregation, precipitation, and fracture of Fe-Ni-Ti-(Mo) maraging steels is crucial for the development of improved steel performance. The addition of Mo effectively suppresses intergranular embrittlement by reducing the segregation of Ni and Ti, inhibiting the formation of coarse Ni3Ti precipitates and precipitate-free zones at grain boundaries, and enhancing grain boundary cohesion.
Article
Materials Science, Multidisciplinary
Q. Li, J. W. Mo, S. H. Ma, F. H. Duan, Y. L. Zhao, S. F. Liu, W. H. Liu, S. J. Zhao, C. T. Liu, P. K. Liaw, T. Yang
Summary: In this study, it was found that the long-standing problem of hydrogen embrittlement (HE) in metallic materials can be effectively eliminated in Fex(CrCoNi)1-x face-centered cubic (fcc) high-entropy alloys (HEAs) by triggering localized segregation of Cr at grain boundaries (GBs). Increasing the Fe concentration significantly improves the HE resistance, reduces ductility loss, and transforms the fracture mode. The increased Fe concentration promotes nanoscale Cr segregation at GBs, enhancing the GBs' cohesive strength and suppressing local hydrogen segregation, thus achieving outstanding HE resistance.
Article
Engineering, Mechanical
Kaidi Li, Bin Tang, Mengqi Zhang, Liguo Zhao, Xudong Liu, Jiangkun Fan, Jinshan Li
Summary: This study developed a hydrogen diffusion model that considers the effects of grain boundaries on hydrogen transportation. The study found that the GB energy plays a control role in and near the GB regions, and that hydrogen exhibits a preference for localization near high-angle grain boundaries and triple junctions. Additionally, in alloys with medium grain size, hydrogen typically had low average concentration with a more uniform distribution.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Petr Rehak, Monika Vsianska, Miroslav Cerny
Summary: In this paper, the segregation of six sp-impurities to the Sigma 5(310)[001] grain boundary in bcc iron is studied from first principles. It is found that while the vibrational contribution to the crystal energy can be relatively high in some cases, the segregation preference of Al, Ga, In, Sn, Sb, and Te remains constant with increasing temperature. Additionally, the presence of segregated impurity atoms is predicted to reduce the grain boundary cohesion based on calculations of the cleavage energy.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Review
Metallurgy & Metallurgical Engineering
Boning Zhang, Yong Mao, Zhenbao Liu, Jianxiong Liang, Jun Zhang, Maoqiu Wang, Jie Su, Kun Shen
Summary: Hydrogen embrittlement poses a serious threat to the safety of metallic materials used in aerospace, ocean, and transportation. Recent research has focused on utilizing microstructural features to trap hydrogen atoms and enhance resistance to hydrogen embrittlement. This review highlights the use of ab initio calculations based on density functional theory (DFT) to predict trapping parameters and understand the electronic/atomistic mechanisms of hydrogen trapping in metallic materials. The challenges and prospects in simulating defect interactions, interpreting experimental characterizations, and developing microstructure-based diffusion prediction models are discussed. The importance of incorporating DFT data to guide composition and microstructure design for hydrogen embrittlement-resistant materials is emphasized.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2023)
Article
Chemistry, Physical
S. Sampath, R. Rementeria, X. Huang, J. D. Poplawsky, C. Garcia-Mateo, F. G. Caballero, R. Janisch
JOURNAL OF ALLOYS AND COMPOUNDS
(2016)
Article
Chemistry, Physical
Emily J. Rabe, Kathryn L. Corp, Xiang Huang, Johannes Ehrmaier, Ryan G. Flores, Sabrina L. Estes, Andrzej L. Sobolewski, Wolfgang Domcke, Cody W. Schlenker
JOURNAL OF PHYSICAL CHEMISTRY C
(2019)
Article
Chemistry, Physical
Kathryn L. Corp, Emily J. Rabe, Xiang Huang, Johannes Ehrmaier, Mitchell E. Kaiser, Andrzej L. Sobolewski, Wolfgang Domcke, Cody W. Schlenker
JOURNAL OF PHYSICAL CHEMISTRY C
(2020)
Article
Chemistry, Physical
Johannes Ehrmaier, Xiang Huang, Emily J. Rabe, Kathryn L. Corp, Cody W. Schlenker, Andrzej L. Sobolewski, Wolfgang Domcke
JOURNAL OF PHYSICAL CHEMISTRY A
(2020)
Article
Chemistry, Physical
Sebastian Pios, Xiang Huang, Wolfgang Domcke
Summary: This study employed ab initio computational methods to investigate the production of hydrated electrons by photodetaching excess hydrogen atoms from the heptazinyl radical, showing that it is a feasible approach and can be achieved from water.
Article
Chemistry, Physical
Maxim F. Gelin, Xiang Huang, Weiwei Xie, Lipeng Chen, Nada Doslic, Wolfgang Domcke
Summary: An ab initio theoretical framework is presented for simulating femtosecond time-resolved transient absorption pump-probe spectra using quasi-classical trajectories, based on a classical approximation to the representation of third-order four-wave-mixing signals. The method involves stochastic sampling of classical trajectories from a positive definite doorway distribution and evaluation of signals by averaging over a positive definite window distribution, to describe nonadiabatic excited-state dynamics. The approach has been demonstrated through simulations of different contributions to the TA PP spectrum of gas-phase pyrazine using the second-order algebraic-diagrammatic construction method.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Chemistry, Physical
Xiang Huang, Wolfgang Domcke
Summary: Polymeric carbon nitrides consisting of heptazine building blocks, particularly the derivative trianisole-heptazine (TAHz), have shown promise as potent photocatalysts for oxidizing various substrates through excited-state proton-coupled electron-transfer reactions. Detailed mechanisms and quantitative insights can be obtained through ab initio computation of energy profiles and reaction dynamics simulations to understand the water oxidation and hydrogen evolution processes.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Physical
Xiang Huang, Weiwei Xie, Nada Doslic, Maxim F. Gelin, Wolfgang Domcke
Summary: The passage discusses the technique of 2D electronic spectroscopy and its application in simulating molecular photodynamics. By using ab initio theoretical framework and classical trajectory simulations, researchers can gain detailed insights into the ultrafast photodynamics of molecules.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2021)
Article
Chemistry, Physical
Siying Zhan, Maxim F. Gelin, Xiang Huang, Kewei Sun
Summary: By using the DW protocol, we conducted ab initio simulations of peak evolutions and beating maps of electronic 2D spectra for a polyatomic molecule in the gas phase. The chosen molecule, pyrazine, is a typical example of photodynamics dominated by CIs. The DW protocol is shown to be a numerically efficient method suitable for simulating 2D spectra for a wide range of excitation/detection frequencies and population times. The peak evolutions and beating maps not only provide information about the timescales of transitions through CIs but also identify the coupling and tuning modes active at these CIs.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Tobias Kaczun, Adrian L. Dempwolff, Xiang Huang, Maxim F. Gelin, Wolfgang Domcke, Andreas Dreuw
Summary: Transient absorption UV pump X-ray probe spectroscopy is a versatile technique for exploring ultrafast photoinduced dynamics in valence-excited states. This work presents an ab initio theoretical framework for simulating time-resolved UV pump X-ray probe spectra. The simulation method is based on the classical doorway-window approximation and a surface-hopping algorithm for nonadiabatic nuclear excited-state dynamics. Results indicate that spectra measured at the nitrogen K edge provide richer information about ultrafast nonadiabatic dynamics in valence-excited states than those measured at the carbon K edge.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Xiang Huang, Wolfgang Domcke
Summary: The excited-state proton-coupled electron-transfer (PCET) reaction in hydrogen-bonded complexes of trianisoleheptazine (TAHz) with phenol derivatives was studied using time-resolved photoluminescence quenching and pump-probe experiments. The PCET reactivity was found to depend on the electron-donating/electron-withdrawing character of the substituents on phenol. Nonadiabatic dynamics simulations provided insights into the PCET reactions in TAHz-phenol complexes, showing faster reaction rates in TAHz-methoxyphenol complexes due to a lower H-atom-transfer barrier.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Sebastian Pios, Xiang Huang, Andrzej L. Sobolewski, Wolfgang Domcke
Summary: Heptazine and its derivatives play crucial roles in photocatalysis and organic optoelectronics, with their unique feature of inverted singlet-triplet gap contributing to efficiency and stability.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2021)
Article
Chemistry, Physical
Xiang Huang, Juan-Pablo Aranguren, Johannes Ehrmaier, Jennifer A. Noble, Weiwei Xie, Andrzej L. Sobolewski, Claude Dedonder-Lardeux, Christophe Jouvet, Wolfgang Domcke
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2020)
