Article
Materials Science, Multidisciplinary
Chaoqiang Liu, Xin Hu, Lin Qi, Houwen Chen, Zhiqiao Li, Xiaoyong Zhang, Hongge Yan, Kechao Zhou, Min Song, Yunzhi Wang, Jian-Feng Nie
Summary: Heterogeneous precipitation of the β phase at boundaries within α' martensite and dislocations greatly affects the mechanical properties of α+β titanium alloys. A novel phenomenon was observed in a Ti-4wt%Mo alloy where the β phase selectively precipitates on Mo-segregated twin boundaries within α' martensite. The unique orientation relationship between the β phase and α' is formed due to the similar structure of the twin boundary and Mo segregation, providing a template for β precipitation and potential improvement in mechanical properties.
Article
Materials Science, Multidisciplinary
Xuan Zhang, Liang Zhang, Zhihui Zhang, Xiaoxu Huang
Summary: First-principles calculations were used to study the segregation behavior of Mg and Cu in different Al grain boundaries and their effects on energy and mechanical properties. The results showed that Mg and Cu both segregated at the grain boundaries, with Cu having a stronger segregation tendency. Mg segregation reduced the grain boundary strength, while Cu segregation enhanced it.
MECHANICS OF MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Hong Ju, Hong Ning, Zhao-Yuan Meng, Cheng Wang, Hui-Yuan Wang
Summary: In this study, the segregation behavior of 19 solute atoms at twin boundaries (TBs) in magnesium alloys was systematically investigated. It was found that smaller solute atoms prefer to occupy compression sites of TBs, while larger solute atoms tend to locate at extension sites. The segregation of solute atoms into preferable sites is attributed to the combined effects of bond strengthening and alleviated lattice distortion in the vicinity of TBs. The results provide guidance for the design of novel magnesium alloys based on TB strengthening.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Jun Hui, Xiaoyong Zhang, Tao Liu, Wenguan Liu, Biao Wang
Summary: This study used first-principles calculations and tensile tests to investigate the effects of 14 metallic solutes on twin boundaries in Ti alloys. By calculating twin formation energies and examining segregation energy, the study identified how solutes influence twin boundary strength, ultimately determining maximum TB strength.
MATERIALS & DESIGN
(2022)
Article
Metallurgy & Metallurgical Engineering
Jiawei Tang, Yiren Wang, Yong Jiang, Jiangang Yao, Hao Zhang
Summary: This study systematically investigates the segregation behaviors of solute elements in Al alloys and their effects on grain boundary binding using first-principles energetics. The results show that solute elements can either enhance or weaken the grain boundary strength, and this effect is always mitigated to some extent by segregated vacancies at the grain boundary.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2022)
Article
Nanoscience & Nanotechnology
Wen-Yu Zhang, Qiu-Jie Chen, Shang-Yi Ma, Shao-Qing Wang
Summary: The local structural features of interfacial twin boundary (ITB) phases at {112}111f and {332}113f twin boundaries (TBs) in beta-Ti alloys are investigated using first-principles calculations. It is found that the formation of ITB-omega at (112)[111]f and (332)[113]f TBs is favorable in kinetics, and the former is further favorable in terms of interfacial energy. The ITB-omega phases are driven by the energy reduction induced by the beta ->omega transformation. On the other hand, the formation of ITB-alpha '' at (332)[113]f TB is infeasible in kinetics and it is likely to be the accompanying or untransformed alpha '' particle assisting (332)[113]f twinning. The origins and tailoring of the ITB-omega and ITB-alpha '' phases by beta-stabilizers such as Mo, Nb, and V are clearly demonstrated.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Multidisciplinary
Zhifeng Huang, Jian-Feng Nie
Summary: This study investigates the interaction of hydrogen with different alloying elements in magnesium alloys at a specific twin boundary, revealing that hydrogen prefers to bond with certain solute elements. These interactions can either enhance or weaken the cohesion of the twin boundary, showcasing the importance of understanding how hydrogen embrittlement occurs in magnesium alloys.
Article
Materials Science, Multidisciplinary
Zhifeng Huang, Jian-Feng Nie
Summary: This study investigates the interactions between common solutes in biodegradable zinc alloys using first-principles calculations. The energetically favorable configurations and segregation abilities of these solutes in the lattice and twin boundary are explored, along with their effects on alloy mechanical properties.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Jiwei Wang, Bin Shao, Debin Shan, Bin Guo, Yingying Zong
Summary: This study used first-principles calculations to investigate the formation of hydrogen-vacancy clusters at twin boundaries in alpha-titanium and their effect on the strength of the boundaries. It was found that the presence of vacancies weakens the twin boundaries by reducing Ti-Ti bonds, but the exact effect depends on the type of twin boundary and the number of hydrogen atoms trapped. These findings provide valuable insights into the role of hydrogen in the embrittlement of alpha-titanium.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Nanoscience & Nanotechnology
Yi-Jia Li, Yuan Fang, Cheng Wang, Zhen-Ming Hua, Yipeng Gao, Min Zha, Hui-Yuan Wang
Summary: The study discovered that twin boundary pinning is a new hardening mechanism in Mg-2Zn-0.5Ca alloy during bake-hardening, enhancing the strength-ductility synergy. The co-segregation of Zn and Ca atoms at twin boundaries effectively suppresses crack propagation, improving the material's ductility.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
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
Chemistry, Physical
Youzhi Gao, Xuyang Liu, Liangxiao Wei, Xuefeng Zhang, Min Chen
Summary: The segregation behavior of elements at the Ti/TiFe coherent interface and its impact on the nucleation, growth, and coarsening of TiFe precipitate were studied through calculation. The results showed that different elements exhibited distinct segregation tendencies at the interface and had varying effects on the TiFe precipitate.
SURFACES AND INTERFACES
(2022)
Article
Multidisciplinary Sciences
Cong He, Zhiqiao Li, Houwen Chen, Nick Wilson, Jian-Feng Nie
Summary: The authors report an unusual solute segregation phenomenon in a group of Mg alloys driven by chemical bonding, where solute atoms larger than Mg segregate to compression sites of specific fully coherent twin boundary.
NATURE COMMUNICATIONS
(2021)
Article
Materials Science, Multidisciplinary
Anna Sophie Ebner, Severin Jakob, Helmut Clemens, Reinhard Pippan, Verena Maier-Kiener, Shuang He, Werner Ecker, Daniel Scheiber, Vsevolod Razumovskiy
Summary: Grain boundary engineering is crucial in designing new materials, especially for nickel-based alloys. By combining advanced experimental and theoretical methods, the grain boundary chemistry of the 725 Ni-base alloy is revealed, providing a way to evaluate the interfacial excess based on the material's heat treatment history and chemistry.
Article
Materials Science, Multidisciplinary
N. S. Harsha Gunda, Richard A. Michi, Matthew F. Chisholm, Amit Shyam, Dongwon Shin
Summary: Al-Ni alloys are promising for high-temperature applications due to the strength of Al3Ni fibers, which are resistant to coarsening and spheroidization up to 400C. However, the characteristics of the interface between Al and Al3Ni phases have not been well understood. In this study, we constructed various supercells to model this interface and performed a first-principles study using density functional theory (DFT). We analyzed the correlation between the DFT Al/Al3Ni interfacial energies and characteristic features, such as excess free volume and the number of broken bonds. Further experimental and computational analysis is needed to improve the interface modeling of Al/Al3Ni.
COMPUTATIONAL MATERIALS SCIENCE
(2023)
Article
Materials Science, Multidisciplinary
Y. Liu, K. Zweiacker, C. Liu, J. T. McKeown, J. M. K. Wiezorek
Summary: The evolution of rapid solidification microstructure and solidification interface velocity of hypereutectic Al-20at.%Cu alloy after laser melting has been studied experimentally. It was found that the formation of microstructure was dominated by eutectic, alpha-cell, and banded morphology grains, and the growth modes changed with increasing interface velocity.
Article
Materials Science, Multidisciplinary
Bharat Gwalani, Julian Escobar, Miao Song, Jonova Thomas, Joshua Silverstein, Andrew Chihpin Chuang, Dileep Singh, Michael P. Brady, Yukinori Yamamoto, Thomas R. Watkins, Arun Devaraj
Summary: Castable alumina forming austenitic alloys exhibit superior creep life and oxidation resistance at high temperatures. This study reveals the mechanism behind the enhanced creep performance of these alloys by suppressing primary carbide formation and offers a promising alloy design strategy for high-temperature applications.
Article
Materials Science, Multidisciplinary
Jian Song, Qi Zhang, Songsong Yao, Kunming Yang, Houyu Ma, Jiamiao Ni, Boan Zhong, Yue Liu, Jian Wang, Tongxiang Fan
Summary: Recent studies have shown that achieving an atomically flat surface for metals can greatly improve their oxidation resistance and enhance their electronic-optical applications. Researchers have explored the use of graphene as a covering layer to achieve atomically flat surfaces. They found that high-temperature deposited graphene on copper surfaces formed mono-atomic steps, while annealed copper and transferred graphene on copper interfaces formed multi-atomic steps.
Article
Materials Science, Multidisciplinary
Jennifer A. Glerum, Jon-Erik Mogonye, David C. Dunand
Summary: Elemental powders of Al, Ti, Sc, and Zr are blended and processed via laser powder-bed fusion to create binary and ternary alloys. The microstructural analysis and mechanical testing show that the addition of Ti results in the formation of primary precipitates, while the addition of Sc and Zr leads to the formation of fine grain bands. The Al-0.25Ti-0.25Zr alloy exhibits comparable strain rates to Al-0.5Zr at low stresses, but significantly higher strain rates at higher stresses during compressive creep testing. Finite element modeling suggests that the connectivity of coarse and fine grain regions is a critical factor affecting the creep resistance of the alloys.
Article
Materials Science, Multidisciplinary
P. Jannotti, B. C. Hornbuckle, J. T. Lloyd, N. Lorenzo, M. Aniska, T. L. Luckenbaugh, A. J. Roberts, A. Giri, K. A. Darling
Summary: This work characterizes the thermo-mechanical behavior of bulk nanocrystalline Cu-Ta alloys under extreme conditions. The experiments reveal that the alloys exhibit unique mechanical properties, behaving differently from conventional nanocrystalline Cu. They do not undergo grain coarsening during extrusion and exhibit behavior similar to coarse-grained Cu.
Article
Materials Science, Multidisciplinary
Yiqing Wei, Jingwei Li, Daliang Zhang, Bin Zhang, Zizhen Zhou, Guang Han, Guoyu Wang, Carmelo Prestipino, Pierric Lemoine, Emmanuel Guilmeau, Xu Lu, Xiaoyuan Zhou
Summary: This study proposes a new strategy to modify microstructure by phase regulation, which can simultaneously enhance carrier mobility and reduce lattice thermal conductivity. The addition of Cu in layered SnSe2 induces a phase transition that leads to increased grain size and reduced stacking fault density, resulting in improved carrier mobility and lower lattice thermal conductivity.
Article
Materials Science, Multidisciplinary
Jia Chen, Zhengyu Zhang, Eitan Hershkovitz, Jonathan Poplawsky, Raja Shekar Bhupal Dandu, Chang-Yu Hung, Wenbo Wang, Yi Yao, Lin Li, Hongliang Xin, Honggyu Kim, Wenjun Cai
Summary: In this study, the structural origin of the pH-dependent repassivation mechanisms in multi-principal element alloys (MPEA) was investigated using surface characterization and computational simulations. It was found that selective oxidation in acidic to neutral solutions leads to enhanced nickel enrichment on the surface, resulting in reduced repassivation capability and corrosion resistance.
Article
Materials Science, Multidisciplinary
X. Y. Xu, C. P. Huang, H. Y. Wang, Y. Z. Li, M. X. Huang
Summary: The limited slip systems of magnesium (Mg) and its alloys hinder their wide applications. By conducting tensile straining experiments, researchers discovered a rate-dependent transition in the dislocation mechanisms of Mg alloys. At high strain rates, glissile dislocations dominate, while easy-glide dislocations dominate at low strain rates. Abundant glissile dislocations do not necessarily improve ductility.
Article
Materials Science, Multidisciplinary
M. S. Szczerba, M. J. Szczerba
Summary: Inverse temperature dependences of the detwinning stress were observed in face-centered cubic deformation twins in Cu-8at.%Al alloy. The detwinning stress increased with temperature when the pi detwinning mode was involved, but decreased when the pi/3 mode was involved. The dual effect of temperature on the detwinning stress was due to the reduction of internal stresses pre-existing within the deformation twins. The complete reduction of internal stresses at about 530 degrees C led to the equivalence of the critical stresses of different detwinning modes and a decrease in the yield stress anisotropy of the twin/matrix structure.
Article
Materials Science, Multidisciplinary
Taowen Dong, Tingting Qin, Wei Zhang, Yaowen Zhang, Zhuoran Feng, Yuxiang Gao, Zhongyu Pan, Zixiang Xia, Yan Wang, Chunming Yang, Peng Wang, Weitao Zheng
Summary: The interaction between the electrode and the electric double layer (EDL) significantly influences the energy storage mechanism. By studying the popular alpha-Fe2O3 electrode and the EDL interaction, we find that the energy storage mechanism of the electrode can be controlled by modulating the EDL.
Article
Materials Science, Multidisciplinary
Matthew R. Barnett, Jun Wang, Sitarama R. Kada, Alban de Vaucorbeil, Andrew Stevenson, Marc Fivel, Peter A. Lynch
Summary: The elastic-plastic transition in magnesium alloy Mg-4.5Zn exhibits bursts of deformation, which are characterized by sudden changes in grain orientation. These bursts occur in a coordinated manner among nearby grains, with the highest burst rate observed at the onset of full plasticity. The most significant burst events are associated with twinning, supported by the observation of twinned structures using electron microscopy. The bursts are often preceded and followed by a stasis in peak movement, indicating a certain "birth size" for twins upon formation and subsequent growth at a later stage.
Article
Materials Science, Multidisciplinary
Vaidehi Menon, Sambit Das, Vikram Gavini, Liang Qi
Summary: Understanding solute segregation thermodynamics is crucial for investigating grain boundary properties. The spectral approach and thermodynamic integration methods can be used to predict solute segregation behavior at grain boundaries and compare with experimental observations, thus aiding in alloy design and performance control.
Article
Materials Science, Multidisciplinary
Feiyu Qin, Lei Hu, Yingcai Zhu, Yuki Sakai, Shogo Kawaguchi, Akihiko Machida, Tetsu Watanuki, Yue-Wen Fang, Jun Sun, Xiangdong Ding, Masaki Azuma
Summary: This study reports on the negative and zero thermal expansion properties of Cd2Re2O7 and Cd1.95Ni0.05Re2O7 materials, along with their ultra-low thermal conductivity. Through investigations of their structures and phonon calculations, the synergistic effect of local structure distortion and soft phonons is revealed as the key to achieving these distinctive properties.
Article
Materials Science, Multidisciplinary
Thomas Beerli, Christian C. Roth, Dirk Mohr
Summary: A novel testing system for miniature specimens is designed to characterize the plastic response of materials for which conventional full-size specimens cannot be extracted. The system has an automated operation process, which reduces the damage to specimens caused by manual handling and improves the stability of the test results. The experiments show that the miniature specimens extracted from stainless steel and aluminum have high reproducibility, and the results are consistent with those of conventional-sized specimens. A correction procedure is provided to consider the influence of surface roughness and heat-affected zone caused by wire EDM.
Article
Materials Science, Multidisciplinary
Rani Mary Joy, Paulius Pobedinskas, Nina Baule, Shengyuan Bai, Daen Jannis, Nicolas Gauquelin, Marie-Amandine Pinault-Thaury, Francois Jomard, Kamatchi Jothiramalingam Sankaran, Rozita Rouzbahani, Fernando Lloret, Derese Desta, Jan D'Haen, Johan Verbeeck, Michael Frank Becker, Ken Haenen
Summary: This study investigates the influence of film microstructure and composition on the Young's modulus and residual stress in nanocrystalline diamond thin films. The results provide insights into the mechanical properties and intrinsic stress sources of these films, and demonstrate the potential for producing high-quality nanocrystalline diamond films under certain conditions.