Article
Nanoscience & Nanotechnology
Yong Li, Wei Li, Shilei Li, Na Min, Laizhu Jiang, Qinglong Zhou, Xuejun Jin
Summary: By regulating the thermomechanical processing parameters, a multi-phase heterostructured microstructure with higher yield strength than the coarse grained counterpart was achieved in this study, with in-depth investigation on microscopic load transfer.
SCRIPTA MATERIALIA
(2021)
Article
Nanoscience & Nanotechnology
Mun Sik Jeong, Tak Min Park, Seunggyu Choi, Seok-Jae Lee, Jeongho Han
Summary: A novel resetting process is proposed in this study to recover the reduced ductility of cold-worked medium-Mn steels by restoring the original microstructure of the steel through simple heat treatment. The ductility of the reset steel is successfully recovered and its strength is improved, simplifying the manufacturing process of automotive components with conflicting attributes.
SCRIPTA MATERIALIA
(2021)
Article
Engineering, Mechanical
Xiaodan Zhang, Shangming Li, Xiaoqian Guo, Huamiao Wang, Qin Yu, Peidong Wu
Summary: In this study, an elastic visco-plastic self-consistent model with twinning and detwinning scheme, along with a torsion specific finite element approach, is used to simulate the deformation behavior of magnesium alloy solid rod with different initial textures. It was found that the deformation mechanisms, stress-strain response, Swift effect, and deformation texture vary significantly with different initial textures and loading paths, highlighting the importance of understanding the influence of these factors on mechanical properties.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2021)
Article
Nanoscience & Nanotechnology
Tak Min Park, Mun Sik Jeong, Chanwon Jung, Won Seok Choi, Pyuck-Pa Choi, Jeongho Han
Summary: By adding a micro-alloying element and forming precipitates, the steel exhibits higher strength without sacrificing ductility compared to steel without precipitates. The formation of precipitates changes the microstructure of the steel and enhances the strain hardening rate, leading to higher tensile strength.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Aniruddha Dutta, Tak Min Park, Jae-Hoon Nam, Sang-In Lee, Byoungchul Hwang, Won Seok Choi, Stefanie Sandloebes, Dirk Ponge, Jeongho Han
Summary: This study reveals that strain partitioning control is essential for improving the mechanical response of medium-Mn steels. By conducting micro digital image correlation analysis, it was found that intercritical annealing treatments can lead to enhanced strength, ductility, and toughness. The LA specimen, with smaller colonies of retained austenite grains, exhibits more homogeneous microstrain distribution and shows more globally TRIP and TWIP behaviors during plastic deformation.
MATERIALS CHARACTERIZATION
(2021)
Article
Materials Science, Multidisciplinary
R. V. Sundeev, A. V. Shalimova, S. O. Rogachev, O. P. Chernogorova, A. M. Glezer, A. V. Ovcharov, I. A. Karateev
Summary: This study investigates the possibility of forming a multi-metal composite by high-pressure torsion (HPT) at room temperature using two dissimilar alloys, Ti50Ni25Cu25 and Fe50Ni33B17. The results show that the consolidation of the dissimilar layers is achieved through mutual severe plastic deformation.
Article
Nanoscience & Nanotechnology
Mahsa Khorrami, Abbas Zarei Hanzaki, Hamid Reza Abedi, Mohammad Moallemi, Javad Mola, Guanghui Chen
Summary: The relationship between microstructure and mechanical properties in Ni-free high N transformation induced plasticity steels at room temperature was studied in this work. Tensile properties were influenced by the Mn content and transformation routes, affecting strain hardening rate and ductility. The formation of martensite before plastic deformation reduced strain partitioning and load transition, while higher strain compatibility between austenite and ferrite resulted in improved uniform elongation and moderate strain hardening rate in the alloy with higher Mn content.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Nanoscience & Nanotechnology
K. M. H. Bhadhon, X. Wang, J. R. McDermid
Summary: This study found that the starting microstructure, intercritical annealing parameters, and Sn micro-alloying significantly influenced the mechanical properties of the steels. A martensitic starting microstructure resulted in a higher volume fraction of stable retained austenite, leading to the desired mechanical properties of third generation advanced high strength steels.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Seok Gyu Lee, Yong Hee Jo, Taejin Song, Hyoung Seop Kim, Byeong-Joo Lee, Seok Su Sohn, Sunghak Lee
Summary: In this study, a new design strategy of high-entropy-alloy-cored multi-layered sheet (MLS) was proposed, named HEA/high-Mn MLS, to enhance the tensile behavior of materials. The interface remained strongly bonded after tensile deformation at both room and cryogenic temperatures, forming unique microstructures that significantly improved both strength and ductility. This design shows potential for developing strong alloys for cryogenic applications with a good strength-ductility balance compared to other high-entropy or medium-entropy alloys.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Metallurgy & Metallurgical Engineering
Chao Lv, Xingmin Huang, Yanhua Wang, Qinqin Fu, Juan Zhang, Min Wu
Summary: The microstructures and mechanical properties of hot-rolled Fe-0.35C-3.2Al-5Mn medium-manganese steels were systematically investigated, showing that ultrafine-grained duplex phases with bimodal morphologies can be obtained through intercritical annealing, resulting in high ultimate tensile strength and total elongation. The newly developed medium-manganese steels demonstrate great practical applications due to their excellent combination of mechanical properties.
STEEL RESEARCH INTERNATIONAL
(2022)
Article
Nanoscience & Nanotechnology
Jin-Young Lee, Jin-Sung Hong, Seok-Hyeon Kang, Young-Kook Lee
Summary: In Fe-17Mn steel, the transition of deformation mechanism from TRIP to TWIP occurs at the late stage of tensile strain when the gamma-austenite grain size decreases and the apparent stacking fault energy increases significantly.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Engineering, Mechanical
Huamiao Wang, Xiaodan Zhang, Wei Wu, Peter K. Liaw, Ke An, Qin Yu, Peidong Wu
Summary: Extensive attention has been given to magnesium (Mg) alloys as potential lightweight structural materials. However, the processing and manufacturing of Mg materials with high strength and good ductility remain challenging. This is mainly due to a lack of understanding of the anisotropic mechanical behavior of Mg alloys under multiaxial stress states. In this study, the torsional and coupled torsion-tension/compression behaviors of a magnesium alloy subjected to large-strain deformation were investigated. Experimental validation was conducted and a model was proposed to capture the complex behavior of Mg alloys under different loading conditions. The findings of this study provide insights for designing and optimizing the properties of Mg alloys.
INTERNATIONAL JOURNAL OF PLASTICITY
(2022)
Article
Materials Science, Multidisciplinary
Alireza Tondro, Masoud Taherijam, Hamidreza Abdolvand
Summary: The presence of hydrogen in the lattice of polycrystalline metals can result in hydrogen embrittlement, and its diffusion and formation depend on various factors. The study combines a non-local crystal plasticity finite element model with hydrogen diffusion equations to investigate the effects of these factors on stress-assisted hydrogen diffusion in zirconium polycrystals. The concentration of hydrogen is found to peak at grain boundaries and triple-junction points, and its effect on trapped hydrogen content can be significant in localized deformation zones.
MECHANICS OF MATERIALS
(2023)
Article
Nanoscience & Nanotechnology
S. H. Sun, M. H. Cai, H. Ding, H. L. Yan, Y. Z. Tian, S. Tang, Peter Hodgson
Summary: This study reports a tri-phase hierarchical lamellar structure to achieve a balance between ultra-high yield strength and high ductility in a Si-Al added medium Mn lightweight TRIP/TWIP steel. By subjecting the warm-rolled sample to small cold rolling and low-temperature tempering, a nano-scale twins and martensitic laths were obtained in the austenitic matrix along with the hard delta-ferrite and nano-precipitates. The tempered sample exhibited a yield strength of 1403 MPa, which was 370 MPa higher than the warm-rolled counterpart. The propagation of plastic strain was confined by the hard zone (delta-ferrite), resulting in an intrinsic hetero-deformation induced (HDI) strengthening effect. The large ductility of 30% was attributed to the elongation of the yield point and enhanced strain hardening after the Luders strain, which were closely associated with HDI hardening and additional TRIP/TWIP effects.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Nanoscience & Nanotechnology
Praveen Sathiyamoorthi, Peyman Asghari-Rad, Gangaraju Manogna Karthik, Alireza Zargaran, Hyoung Seop Kim
Summary: Fe40Mn40Co10Cr10 twinning induced plasticity high-entropy alloy processed by high-pressure torsion shows no typical grain refinement, but retains original grain size with the formation of strain-induced HCP martensitic phase.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Yi Liu, Bo Gao, Ming Yang, Lirong Xiao, Jiaxin Wang, Jiaxin Ma, Xiangjie Chen, Hao Zhou, Yuntian Zhu
Summary: The improvement of strength in low-carbon steel usually leads to a reduction in ductility due to the low strain-hardening rate of ultrafine-grained materials. The heterostructured strategy, achieved through phase transformation, offers a new way to enhance the strain-hardening rate. In this study, intercritical annealing was used to produce a dual-phase heterostructure in low-carbon steel, leading to improved strength and ductility. The presence of ferrite and martensite in the heterostructured steel resulted in a higher density of low-angle grain boundaries and geometrically necessary dislocations, promoting strain partitioning and ultimately improving the combination of strength and ductility.
Article
Materials Science, Multidisciplinary
X. X. Dong, Y. F. Shen, Y. T. Zhu
Summary: A principle is proposed and verified that an optimized moderate strain hardening rate is desired for producing the best mechanical properties for metallic materials. It is demonstrated that moderate strain hardening rate is desired for better ductility and high yield strength in a medium carbon TRIP steel. By adjusting the temperature for bainitic transformation, the TRIP kinetics were tailored to produce moderated but long-lasting strain hardening for high ductility and high yield strength.
MATERIALS RESEARCH LETTERS
(2023)
Article
Engineering, Mechanical
Hao Zhang, Xiaoqin Ou, Song Ni, Hongge Yan, Xiaozhou Liao, Min Song
Summary: The twinning mechanisms in pure Ti, including {11 (2) over bar1} twinning and {11 (2) over bar2}-{11 (2) over bar1} double twinning, are systematically investigated using molecular dynamics simulations. The migration of {11 (2) over bar1} twin boundaries is mainly carried out by the slip of twinning dislocations. Two double twinning mechanisms, involving the formation and growth of {11 (2) over bar1} twin at the {11 (2) over bar2} twin tip, are discovered. The interfacial structures of {11 (2) over bar1} twins exhibit terraced character with short coherent facets and coherent twin boundary segments.
INTERNATIONAL JOURNAL OF PLASTICITY
(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
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.
Letter
Materials Science, Multidisciplinary
Hao Zhang, Bingqiang Wei, Xiaoqin Ou, Song Ni, Xiaozhou Liao, Min Song
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Wenyu Chen, Rui Zhou, Wanpeng Li, Yen-Hsiang Chen, Tzu-Hsiu Chou, Xu Wang, Yong Liu, Yuntian Zhu, J. C. Huang
Summary: The corrosion behaviors of selective laser melted FeCoCrNi multi-principal element alloys with carbon or nitrogen addition in 0.5 M H2SO4 solution were investigated. Carbon and nitrogen additions refined the grains and introduced a heterogeneous structure, but had opposite effects on corrosion behavior. Doped carbon participated as nano-sized carbides and caused localized galvanic corrosion, while doped nitrogen formed CrN chemical clusters and resulted in a protective passive film with higher Cr2O3/Cr(OH)3 ratio.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Multidisciplinary Sciences
Tingting Song, Zibin Chen, Xiangyuan Cui, Shenglu Lu, Hansheng Chen, Hao Wang, Tony Dong, Bailiang Qin, Kang Cheung Chan, Milan Brandt, Xiaozhou Liao, Simon P. P. Ringer, Ma Qian
Summary: This study demonstrates a series of titanium-oxygen-iron compositions with outstanding tensile properties, achieved through alloy design and additive manufacturing. These alloys, strengthened by the abundant elements of oxygen and iron, offer potential for diverse applications and the industrial-scale use of waste sponge titanium. Additionally, they have significant economic and environmental potential for reducing the carbon footprint of energy-intensive sponge titanium production.
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
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
Nanoscience & Nanotechnology
Yanfang Liu, Jie Ren, Jian Liu, Yang Cao, Wei Liu, Tianyi Li, Yuntian Zhu, Wen Chen
Summary: The AM CoCrFeMnNi alloy, produced by laser powder-bed fusion, exhibits prominent cellular dislocation structures and exceptional thermal stability with high hardness at elevated temperatures. The low crystallographic misorientations across the dislocation cell walls, sluggish atomic diffusion, and pinning effects of oxide nanoprecipitates are the key factors contributing to this outstanding thermal stability.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
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
L. K. Huang, F. Liu, M. X. Huang
Summary: The bainite transformation in medium Mn steels has been experimentally and theoretically studied, and it has been found that the transformation kinetics is slow. However, the introduction of dislocations can significantly accelerate the transformation rate. A new "carbon depletion mechanism" is proposed to explain the role of dislocations in the acceleration of bainite transformation, and a physical model is developed to quantitatively understand the kinetics of bainite transformation.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2024)
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.
