Article
Materials Science, Multidisciplinary
Suqin Zhu, Han-Cheng Shih, Xiangyuan Cui, Chung-Yi Yu, Simon P. Ringer
Summary: The study focuses on solute clustering in Al alloys and demonstrates the effects of pre-ageing treatment on clustering states and alloy properties. Utilizing atom probe tomography and density functional theory simulations, the atomic-scale microstructure arising from the thermomechanical process is revealed.
Article
Nanoscience & Nanotechnology
Z. H. Li, S. Gao, T. T. Sasaki, T. Nakata, S. Kamado, N. Tsuji, K. Hono
Summary: Clarifying the origin of the yielding phenomenon is crucial for improving the flow stability and surface finish of magnesium alloy sheet products. This study investigates the effect of Zn addition on discontinuous yielding in low-alloyed magnesium alloy sheets and reveals the significant impact of Zn on yield-drop. Transmission electron microscopy and atom probe tomography analysis demonstrate the influence of Ca-Zn co-clusters on dislocations, and different stretching directions of the sheet result in distinct Luders deformations.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Jae-Gil Jung, Amir R. Farkoosh, David N. Seidman
Summary: The precipitation behavior of two L1(2)-strengthened alloys with Mg and Y additions was studied. It was found that Si-added alloy forms beta-Mg2Si precipitates at around 200 degrees C, which act as nucleation sites for the L1(2)-nanoprecipitates and cause partial depletion of Si solute atoms, resulting in a microhardness peak at 475 degrees C. The Si-free alloy has superior creep properties due to a larger lattice parameter mismatch of the L1(2)-nanoprecipitates with the Al matrix provided by higher Sc/Er/Y concentrations. Both alloys exhibit slower L1(2) nanoprecipitation-kinetics and extremely high coarsening resistance.
Article
Chemistry, Physical
Atekeh Abolhasani, Brian Langelier, Michael J. Worswick, Mary A. Wells, Shahrzad Esmaeili
Summary: The effects of natural aging on the strengthening behavior and microstructural characteristics of AA7xxx alloys are investigated. The study employs hardness measurement, tensile testing, differential scanning calorimetry, and atom probe tomography. It is found that AA7xxx alloys with similar copper content exhibit similar evolution of yield strength and natural aging rates. Microstructural analysis identifies three types of precipitates in the as-quenched and naturally-aged conditions of AA7075. Nucleation of Zn-Mg precipitates is the dominant precipitation phenomenon during natural aging. A reverse yield strength modeling methodology is used to analyze the natural aging kinetics of different AA7xxx alloys and validate the results with experimental data. The research demonstrates that compositional similarities lead to similar precipitation kinetics during natural aging, and the model predictions agree well with experimental results.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Materials Science, Multidisciplinary
Zi Yang, Igor Erdle, Chunhui Liu, John Banhart
Summary: Differential scanning calorimetry (DSC) is a widely used technique for analyzing precipitation phenomena in alloys. However, the processes occurring during non-isothermal heating, such as cluster formation and evolution, are not well understood. In this study, we conducted experiments to measure heat, hardness, positron lifetime, electrical resistivity, and microstructure of an Al-Mg-Si alloy heated at different rates. We found that the precipitation process can be divided into stages with transition temperatures depending on the heating rate. Quenched-in excess vacancies were found to play an important role in cluster formation at lower temperatures. The results can be well simulated using a precipitation model. The methodology used in this study can be applied to investigate more complex nonisothermal heat treatments.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Z. H. Li, T. T. Sasaki, A. Uedono, K. Hono
Summary: This study investigates the role of Zn in the rapid age-hardening process of magnesium alloys. The results show that the addition of Zn facilitates the formation of Ca-Zn co-clusters, which contributes to the rapid age-hardening.
SCRIPTA MATERIALIA
(2022)
Article
Materials Science, Multidisciplinary
Sigurd Wenner, Constantinos Hatzoglou, Eva Anne Mortsell, Petter Asholt
Summary: High-Si aluminum foundry alloys gain strength through the formation of nanoprecipitates upon heat treatment. Room-temperature storage affects the kinetics of early aging, with Cu additions accelerating the formation of hardening precipitates. However, 1 month of room-temperature storage negates the positive effect of Cu. The solubility limits of Si and Mg during solution heat treatment temperature mainly limit the maximum achievable strength. This study contributes to understanding the solute balance, early aging kinetics, and differences between wrought and foundry alloys through transmission electron microscopy and atom probe tomography analysis.
Article
Materials Science, Multidisciplinary
S. Medrano, H. Zhao, B. Gault, F. De Geuser, C. W. Sinclair
Summary: The softening and strengthening effects in pre-deformed and aged Al-Mg-Cu alloys were evaluated using microscopy, mechanical testing and modeling. A refined model for work hardening response was found to accurately determine the precipitation hardening contribution. The mechanical response of these alloys was not significantly affected by Cu content, pre-deformation level or aging temperature, indicating robustness in terms of composition variations.
Article
Chemistry, Physical
Hisao Shishido, Yasuhiro Aruga, Yuya Murata, Calin Marioara, Olaf Engler
Summary: This study evaluated the characteristics of precipitates and clusters in two model Al-Mg-Si alloys with different Mg/Si ratios using TEM and APT. The relationship between precipitates and clusters significantly influences the mechanical properties of the alloys.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Chemistry, Physical
InSu Kim, MinYoung Song, JaeHwang Kim
Summary: The effects of Cu addition on clustering and two-step aging behavior in Al-Mg-Si-Cu alloys were analyzed, showing that cluster formation is influenced by Cu content and aging temperature, with different Cu contents resulting in different effects. Hardness testing can confirm the presence of clusters and thermal instability effects.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Peng Zhang, Kunkun Shi, Jianjun Bian, Jinyu Zhang, Yong Peng, Gang Liu, Alexis Deschamps, Jun Sun
Summary: The study investigates the effects of solute clusters on the mechanical properties of a commercial Al-Zn-Mg alloy during natural aging (NA). It is found that dense solute clusters enhance the yield strength and strain hardening ability of the alloy without affecting dislocation density evolution. Solute clusters undergo a dissolution-to-coarsening transition during deformation, potentially contributing to the high strain hardening rate observed.
Article
Nanoscience & Nanotechnology
Zi Yang, Xiaohe Jiang, Xingpu Zhang, Meng Liu, Zeqin Liang, David Leyvraz, John Banhart
Summary: During quenching of aluminium alloys, the preservation and loss of excess vacancies have a significant impact on the material properties, with different cooling rates leading to variations in the amount of excess vacancies. Interactions between excess vacancies and early-stage solute clusters play a role in equalizing vacancy fractions in differently quenched samples during the natural ageing process.
SCRIPTA MATERIALIA
(2021)
Article
Materials Science, Multidisciplinary
Zhen-Ming Hua, Cheng Wang, Tian-Shuai Wang, Chunfeng Du, Shen-Bao Jin, Gang Sha, Yipeng Gao, Hai -Long Jia, Min Zha, Hui -Yuan Wang
Summary: This study demonstrates that cyclic deformation of a Mg alloy at room temperature can significantly increase the yield strength while only slightly reducing the elongation to failure. The strength improvement is mainly attributed to the formation of high-density solute clusters. This work provides new insights into the strengthening mechanisms and has important implications for the development of Mg alloys with high strength-ductility synergy.
Article
Materials Science, Multidisciplinary
Jonas K. Sunde, Calin D. Marioara, Sigurd Wenner, Randi Holmestad
Summary: This study examined an Al-0.54Mg-0.38Si (at.%) conductor alloy (6101) subjected to two different thermomechanical processing routes. The results showed that re-ageing after rolling caused a rapid increase in electrical conductivity, which could largely be explained by two precipitate formation mechanisms leading to increased solute depletion of the Al matrix in the deformed material, as quantified by atom probe tomography. Clear differences in precipitate distributions between the deformed and undeformed material were also observed.
MATERIALS CHARACTERIZATION
(2021)
Article
Materials Science, Multidisciplinary
J. R. Famelton, C. A. Williams, C. Barbatti, P. A. J. Bagot, M. P. Moody
Summary: This study introduces a new method called point excess solute for quantifying solute segregation in datasets with limited spatial resolution. Experimental results show that this method can accurately reproduce the expected values in synthetic datasets and observe the inaccuracy of quantification when the dataset resolution is too low. The method is then applied to naturally aged solute clusters in the Al-Mg-Si-Cu system, showing that the formation of solute clusters is unaffected by the Cu content in the alloy.
MATERIALS CHARACTERIZATION
(2023)
Article
Chemistry, Physical
Peng Zhang, Majid Laleh, Anthony E. Hughes, Ross K. W. Marceau, Tim Hilditch, Mike Yongjun Tan
Summary: Although studies on hydrogen embrittlement have been conducted for a long time, there is a lack of systematic research on the susceptibility of steels to hydrogen embrittlement under different electrochemical charging conditions. This study focuses on this knowledge gap by evaluating the behavior of a typical pipeline steel (X65) after hydrogen-charging in different electrolytes that simulate industrial environments. The results show that the susceptibility to hydrogen embrittlement of X65 steel varies significantly with the hydrogen-charging electrolytes and, to a lesser extent, with the electrochemical charging variables.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Materials Science, Multidisciplinary
Mujin Yang, Chao Huang, Jiajia Han, Haichen Wu, Yilu Zhao, Tao Yang, Shenbao Jin, Chenglei Wang, Zhou Li, Ruiying Shu, Cuiping Wang, Huanming Lu, Gang Sha, Xingjun Liu
Summary: A typical G-phase strengthened ferritic model alloy was carefully studied using experimental and theoretical techniques. The study revealed nanoscale microstructural evolutions and elemental segregation during the solid solution and aging process, resulting in increased hardness and severe embrittlement. Cold rolling and aging process effectively suppressed brittle fracture and achieved superhigh yield strength.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Han Lin Mai, Xiang-Yuan Cui, Daniel Scheiber, Lorenz Romaner, Simon P. Ringer
Summary: This study investigates the segregation and co-segregation effects of phosphorus (P) and transition metal (TM) elements at grain boundaries (GBs) in steels. The findings reveal that while P alone is unlikely to cause intergranular fracture, its stronger segregation binding compared to TMs can explain its ubiquitous presence at GBs. The repulsive interactions and strong segregation binding of P deplete cohesion-enhancing solutes at general GBs and favor cohesion-lowering P-TM co-segregation combinations. These mechanisms contribute to P-induced temper embrittlement in alloyed steels and have significant implications for GB engineering.
Article
Materials Science, Multidisciplinary
Yong Chen, Hongmei Zhu, Pengbo Zhang, Zhongchang Wang, Meng Wang, Gang Sha, He Lin, Jingyuan Ma, Zhenyuan Zhang, Yong Song, Pengfei Zheng, Lihua Zhou, Sheng Li, Hao Liu, Longzhang Shen, Changjun Qiu
Summary: The effective strategy to enhance impurity tolerance in structural steel is to increase solidification rate. By using laser additive manufacturing, we successfully engineered C, N and O with high contents as interstitial atoms coordinated with Cr in the form of short-range ordered assembly, resulting in the development of an impurity-tolerant supersaturated austenitic stainless steel with high strength, good ductility, enhanced corrosion resistance, and acceptable thermal stability.
Article
Materials Science, Multidisciplinary
Zizheng Song, Ranming Niu, Xiangyuan Cui, Elena V. Bobruk, Maxim Yu. Murashkin, Nariman A. Enikeev, Ji Gu, Min Song, Vijay Bhatia, Simon P. Ringer, Ruslan Z. Valiev, Xiaozhou Liao
Summary: Superplastic deformation of polycrystalline materials is usually achieved by diffusion-assisted grain boundary sliding at high temperatures. Recent research has shown that room-temperature superplasticity can be achieved in ultrafine-grained Al-Zn based alloys, but the underlying mechanism is still unclear. This study utilized in-situ tensile straining, electron microscopy characterization, and atomistic density functional theory simulation to reveal that the superplasticity at room temperature is achieved by grain boundary sliding and grain rotation, facilitated by the continuous diffusion of Zn. The diffusion of Zn atoms from grains to grain boundaries forms a Zn nanolayer, acting as a solid lubricant to lower the energy barrier of grain boundary sliding.
Article
Multidisciplinary Sciences
Qiang Lu, Jianchuan Wang, Hongcheng Li, Shenbao Jin, Gang Sha, Jiangbo Lu, Li Wang, Bo Jin, Xinyue Lan, Liya Li, Kai Li, Yong Du
Summary: Coarsening of precipitates in medium and high temperatures causes reduction in strength of Al alloys. Here, the authors design an Al-Cu-Mg-Ag-Si-Sc alloy with multiple interface structures, showing an excellent combination of strength and heat resistance compared to conventional Al alloys.
NATURE COMMUNICATIONS
(2023)
Article
Chemistry, Multidisciplinary
Hongwei Liu, Keita Nomoto, Anna V. Ceguerra, Jamie J. Kruzic, Julie Cairney, Simon P. Ringer
Summary: This study develops a new software tool for calculating Pair distribution function (PDF) from electron diffraction patterns (EDPs). The software tool features accurate background subtraction and automatic conversion of different diffraction intensity profiles into a PDF. The study also evaluates the effects of background subtraction and elliptical distortion on PDF profiles. The EDP2PDF software provides a reliable tool for analyzing the atomic structure of both crystalline and non-crystalline materials.
JOURNAL OF APPLIED CRYSTALLOGRAPHY
(2023)
Article
Nanoscience & Nanotechnology
X. Zhou, J. Chen, R. Ding, H. Wu, J. Du, J. He, W. Wang, W. Sun, Y. Liu, G. Sha, H. Pan
Summary: A novel C-doped high entropy alloy (Al0.5CoFeNiC0.1) with nano-scale coherent precipitates was successfully designed and fabricated by arc-melting. The effect of nano-sized particles on the mechanical behavior of the alloy has been evaluated by tensile testing. DFT simulation shows that C triggers the ordered arrangement of Al and Fe/Ni/Co, thus promoting the formation of k' phase. The addition of 2.8 at.% C to as-cast Al0.5CoFeNi leads to a high volume fraction of k0 precipitates with an average size of -35 nm, enhancing dramatically the yield strength compared to its carbon-free counterpart.
MATERIALS TODAY NANO
(2023)
Article
Engineering, Mechanical
Xiyuan Zhang, Guisen Liu, Linfeng Jiang, Dian Jiao, Jimiao Jiang, Chun Chen, Zhiqiang Gao, Jialin Niu, Gang Sha, Yao Shen, Hua Huang, Guangyin Yuan
Summary: In this study, a Zn-2Cu-0.8Li alloy with both high strength and high ductility is developed via a unique hierarchical structure. The alloy consists of a hard beta-LiZn4 matrix, a soft eta-Zn phase, and dispersive epsilon-CuZn4 nanoprecipitates. The alloy exhibits excellent mechanical properties due to the unique microstructure and shows great potential for broader biomedical applications.
INTERNATIONAL JOURNAL OF PLASTICITY
(2023)
Article
Materials Science, Multidisciplinary
Xuzhou Gao, Wei Jiang, Yiping Lu, Zhigang Ding, Jizi Liu, Wei Liu, Gang Sha, Tongming Wang, Tingju Li, Isaac T. H. Chang, Yonghao Zhao
Summary: In this study, a face-centered cubic non-equiatomic Cr26Mn20Fe20Co20Ni14 high-entropy alloy with a low stacking fault energy was prepared and demonstrated excellent strength and ductility over a wide temperature range, including cryogenic temperatures. The microstructural analysis revealed different deformation mechanisms at different temperatures, contributing to the superior tensile properties at cryogenic temperatures. This study provides experimental evidence for the potential cryogenic applications of high-entropy alloys.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Xudong Liu, Jiangkun Fan, Dian Jiao, Bin Tang, Hongchao Kou, Gang Sha, Jinshan Li
Summary: Nanoscale delta phases and multiple deformation mechanisms were introduced into Inconel 625 superalloy via short-term stress-aging treatment (SAT), which is 10 times more efficient than the conventional aging method. The SAT alloy exhibits superior yield strength (779.6 MPa) and elongation (53.8%), surpassing all Inconel 625 superalloys reported in the past decade, including additive manufacturing and forging alloys. The high yield strength is attributed to the blocking effect of nanoscale delta phases and LomerCottrell (L-C) locks. Transmission electron microscopy observations reveal the synergistic effect of L-C locks, dislocation slip, and twinning in improving work hardening ability during tensile deformation. These findings provide new insights for enhancing the mechanical properties of Ni-based superalloys.
SCRIPTA MATERIALIA
(2023)
Article
Chemistry, Physical
Haijiao Lu, Nasir Uddin, Zhehao Sun, Zibin Chen, Zackaria Mahfoud, Yilan Wu, Ary Anggara Wibowo, Zhicheng Su, Xinmao Yin, Chi Sin Tang, Xiaozhou Liao, Simon P. Ringer, Xiu Song Zhao, Andrew T. S. Wee, Michel Bosman, Zongyou Yin
Summary: By integrating plasmonic bismuth nanoparticles and non-plasmonic redox heterojunctions, we have successfully achieved high activity and selectivity in the transformation of CO2 into methanol. This is achieved through the use of localized surface plasmon resonances (LSPRs) to direct the reaction pathways and optimize product selectivity.
Article
Engineering, Manufacturing
Bryan Lim, Keita Nomoto, Amy J. Clarke, Sudarsanam Suresh Babu, Sophie Primig, Xiaozhou Liao, Andrew J. Breen, Simon P. Ringer
Summary: Complex geometries and topology optimisations are driving the additive manufacturing of Ni-based superalloys, but there are thermal signature differences in complex components compared to commonly studied test coupons, leading to unaccounted microstructure-property variations. The effects of topological changes, such as engineered internal voids, on the mechanical performance of as-fabricated Haynes 282 monolith are investigated, revealing the influence of changing thermal conditions on the local mechanical property response.
ADDITIVE MANUFACTURING
(2023)
Article
Engineering, Manufacturing
Nana Kwabena Adomako, Nima Haghdadi, James F. L. Dingle, Ernst Kozeschnik, Xiaozhou Liao, Simon P. Ringer, Sophie Primig
Summary: Metal additive manufacturing is an ideal technique for producing complex shaped engineering parts, but advanced control of microstructures and properties through modeling is necessary. This study presents a computational modeling approach to predict and optimize the microstructures and properties during metal additive manufacturing.
ADDITIVE MANUFACTURING
(2023)
Article
Materials Science, Multidisciplinary
Zhiheng Zhang, Hansheng Chen, Jiaying Jin, Bryan Lim, Xiaolian Liu, Wei Li, Mi Yan, Simon P. Ringer
Summary: This study presents a multi-main-phase Nd-Dy-Fe-B magnet with a Dy-lean core-Dy-rich shell microstructure, which exhibits high magnetic performance and thermal stability. The formation mechanism of the core-shell microstructure is explained through experimental and simulation analysis, highlighting the potential application of the magnet in large-scale production.
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.
