Article
Materials Science, Multidisciplinary
Huizi Chen, Jian Wang, Xiangchen Meng, Yuming Xie, Yulong Li, Long Wan, Yongxian Huang
Summary: Utilizing friction stir processing, an ultrafine-grained structure was achieved in Mg-Zn-Y-Zr alloy leading to extraordinary superplasticity. Grain refinement and homogeneous dispersion of precipitates were promoted by the coupled thermo-mechanical effect, resulting in an ultra-fined grains size of 1.9 +/- 0.4 μm and a superplastic elongation of 642%. Grain boundary sliding was considered as the predominant superplastic deformation mechanism in ultrafine-grained materials.
Article
Materials Science, Multidisciplinary
Wenwei Gao, Hai Wang, Konrad Koenigsmann, Shuyuan Zhang, Ling Ren, Ke Yang
Summary: In this study, a series of Ti-15Zr-xCu alloys were designed and fabricated to refine the grain size and suppress grain growth. Experimental results showed that Cu alloying significantly improved the mechanical properties of the alloys, resulting in better comprehensive mechanical performance.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2022)
Article
Materials Science, Multidisciplinary
Xiaoyan Feng, Xue Pang, Xu He, Ruihong Li, Zili Jin, Huiping Ren, Tingting Liu
Summary: In this study, the hot workability of Mg-1Li-1Al (LA11) alloy was evaluated through a uniaxial compression test. The flow stress was found to increase with higher strain rates and lower deformation temperatures, and a constitutive equation was established based on the hyperbolic sine equation. The activation energy was determined to be 116.5 kJ/mol, and the dynamic recrystallization mechanism was investigated using the Avrami equation. The relationship between DRX volume fraction and deformation parameter was verified based on microstructure evolution.
Article
Materials Science, Multidisciplinary
Mozhgan Shokri, Abbas Zarei-Hanzaki, Hamid Reza Abedi, Jae Hyung Cho
Summary: The study investigated the correlation between microstructure/texture evolutions and high temperature flow behavior in Mg alloy containing long period stacking order (LPSO) phases. The annealing treatment effectively strengthened the alloy and decreased ductility, with blocky LPSO assisting dynamic recrystallization and lamellar LPSO increasing alloy strength. The findings suggest that microstructure and texture evolution play a significant role in the high-temperature behavior of the Mg alloy.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Chemistry, Physical
Boning Wang, Feng Wang, Zhi Wang, Le Zhou, Zheng Liu, Pingli Mao
Summary: In this study, ultrafine-grained Mg-3Zn-1.2Ca-0.6Zr alloy was prepared using a novel extrusion-shear process. The compressive deformation process was found to follow three stages with twinning and dislocation slip playing a significant role in the evolution of the alloy's microstructure. Increase in strain rate promoted interaction between twin and dislocation slip, leading to enhanced deformation, while the dominance of dislocation mechanism was observed in the later stage with increasing dislocation density.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Z. Aalipour, A. Zarei-Hanzaki, A. Moshiri, H. R. Abedi, Daudi Waryoba, A. Kisko, L. P. Karjalainen
Summary: The microstructure and microtexture changes of an extruded and annealed magnesium alloy were investigated under different strain and processing conditions. The results showed that the material underwent noticeable refinement even at low applied compressive strain. Recrystallization process was completed at a true strain of 0.3, and grain refinement was attributed to the LSN and CDRX mechanisms. At higher strain levels, most grains were found in deformed states and the microtexture only changed in terms of intensity.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2022)
Article
Nanoscience & Nanotechnology
B. Tripathy, S. R. K. Malladi, P. P. Bhattacharjee
Summary: The microstructure and properties of cobalt-free AlCrFe2Ni2 high entropy alloy were investigated both in the as-cast condition and after severe cold-rolling and annealing. The alloy showed a heterogeneous microstructure with a high fraction of ductile FCC phase, allowing heavy cold-rolling and resulting in intriguing microstructural features. After annealing, the alloy exhibited ultrafine microduplex structure with significant resistance to grain growth, leading to high yield and tensile strength coupled with appreciable elongation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
Yi Li, Yanjin Guan, Hu Chen, Jiqiang Zhai, Jun Lin, Liang Chen
Summary: During hot compression, the samples of LA43M Mg-Li alloy undergo twinning and dynamic recrystallization processes, where twinning influences the occurrence of dynamic recrystallization and plays a crucial role in microstructure development.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Nanoscience & Nanotechnology
Yan Long, Kebo Liao, Xiaolong Huang
Summary: The study found the formation of dynamic recrystallization-induced micro shear bands in an ultrafine-grained Ti-6Al-4V alloy under quasi-static compression. The localized strain regions experienced a two-step recrystallization process, resulting in refined DRX grains and nanograins. Micro shear bands nucleated, widened, multiplied, and propagated with increasing local strains.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Materials Science, Multidisciplinary
T. S. Orlova, D. I. Sadykov, D. V. Danilov, N. A. Enikeev, M. Yu. Murashkin
Summary: By modifying the alloy's defect structure, the elongation to failure of ultrafine-grained Al-Cu-Zr alloy can be notably increased. This phenomenon is discussed in terms of interfacial dislocation emission and interaction of dislocations with grain boundaries in different states.
Article
Metallurgy & Metallurgical Engineering
Yuxuan Liu, Yangxin Li, Qingchun Zhu, Huan Zhang, Xixi Qi, Duofei Zheng, Yunliang Li, Dezhi Zhang, Xiaoqin Zeng
Summary: The local deformation behavior and dynamic recrystallization of shock compressed Mg-1Zn alloy were investigated using EBSD and TEM. The suppression of dislocation slipping and twinning during high strain-rate deformation activated a more flexible kinking deformation, facilitating slipping and twinning within the kinks. The kink bands evolved into deformation bands with recrystallized nano-grains due to slow heat dissipation and local temperature elevation. This finding provides a new perspective on kinking-facilitated nanocrystallization in Mg alloys and other anisotropic metallic materials.
JOURNAL OF MAGNESIUM AND ALLOYS
(2023)
Article
Materials Science, Multidisciplinary
Ling Zhang, Xiaoyu Wu, Xindong Yang, Yinglong Li
Summary: A study was conducted to investigate the static recrystallization and precipitation behavior of a forged Mg-8.7Gd-4.18Y-0.42Zr alloy annealed at 250-400 degrees Celsius using OM, SEM, TEM, and EBSD methods. The forging process resulted in the formation of coarse grains with parallel and intersecting twins in the microstructure, as well as smaller grains with only parallel twins. During annealing, the presence of twins promoted continuous static recrystallization, with the intersected extension twins being less stable in coarse grains but more conducive to nucleation for recrystallization. Precipitation occurred concurrently with static recrystallization, impeding the growth of the recrystallized grains.
MATERIALS TODAY COMMUNICATIONS
(2023)
Article
Metallurgy & Metallurgical Engineering
Qian Cheng, Liang Chen, Jianwei Tang, Guoqun Zhao, Lu Sun, Cunsheng Zhang
Summary: The microstructure evolution of Mg-5.65Zn-0.66Zr alloy was studied through hot compression tests, revealing the significant impact of dynamic recrystallization on grain structure. High temperature and strain rate affected flow stress and resulted in the split of basal texture.
JOURNAL OF MAGNESIUM AND ALLOYS
(2021)
Article
Chemistry, Physical
T. S. Orlova, T. A. Latynina, M. Y. Murashkin, F. Chabanais, L. Rigutti, W. Lefebvre
Summary: The paper investigates the effect of high pressure torsion on the microstructure, mechanical properties, and electrical conductivity of Al-0.53Mg-0.27Zr alloy preliminarily aged at T = 375 degrees C for 366 h. It was found that HPT processing leads to a significant increase in strength and good electrical conductivity and ductility in the alloy. The study also highlights the key role of Mg alloying elements in strengthening the material.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Chemistry, Physical
Xiaohuan Pan, Lifei Wang, Yongqiao Li, Liangliang Xue, Pengbin Lu, Guangsheng Huang, Bin Xing, Liuwei Zheng, Hongxiang Wang, Fugang Qi, Maurizio Vedani
Summary: This study investigates the interrelation of dynamic recrystallization and detwinning behaviors in a commercial rolled AZ31 Mg alloy sheet. The results show that the dynamic recrystallization and detwinning have different influences on the microstructure evolution at different temperatures. The activation of non-basal slips at elevated temperatures affects the dynamic recrystallization behaviors and accommodates deformation strain.
JOURNAL OF ALLOYS AND COMPOUNDS
(2022)
Article
Microscopy
A. J. Breen, A. C. Day, B. Lim, W. J. Davids, S. P. Ringer
Summary: In this study, a method was developed to enhance the contrast of poles and zone lines in atom probe data by plotting crystallographically correlated metrics. This method can be applied to a wide range of crystalline datasets where crystallographic information is not readily apparent from existing methods, and it helps to gain a deeper understanding of field evaporation behavior during atom probe experiments.
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
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.
Letter
Materials Science, Multidisciplinary
Hao Zhang, Bingqiang Wei, Xiaoqin Ou, Song Ni, Xiaozhou Liao, Min Song
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
Multidisciplinary Sciences
Yangyang Liu, Can Li, Chunhui Tan, Zengxia Pei, Tao Yang, Shuzhen Zhang, Qianwei Huang, Yihan Wang, Zheng Zhou, Xiaozhou Liao, Juncai Dong, Hao Tan, Wensheng Yan, Huajie Yin, Zhao-Qing Liu, Jun Huang, Shenlong Zhao
Summary: The chlor-alkali process is important in the chemical industry due to the diverse usage of chlorine gas. However, current chlorine evolution reaction (CER) electrocatalysts have inefficiencies that result in high energy consumption. This study presents a highly active single-atom ruthenium catalyst for the electro synthesis of chlorine in seawater-like solutions. The catalyst exhibits low overpotential and high stability and selectivity, offering potential for efficient chlorine production from seawater.
NATURE COMMUNICATIONS
(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
Chemistry, Multidisciplinary
Xiang Ding, Xiangyuan Cui, Li-Ting Tseng, Yiren Wang, Jiangtao Qu, Zengji Yue, Lina Sang, Wai Tung Lee, Xinwei Guan, Nina Bao, Ci Sathish, Xiaojiang Yu, Shibo Xi, Mark B. H. Breese, Rongkun Zheng, Xiaolin Wang, Lan Wang, Tom Wu, Jun Ding, Ajayan Vinu, Simon P. Ringer, Jiabao Yi
Summary: In this work, Ni/NiO nanocomposites were fabricated by depositing Ni and NiO thin layers alternately and annealing them at specific temperatures. It was found that the samples annealed at 473 K exhibited a significantly enhanced saturation magnetization exceeding 607 emu cm-3 at room temperature, surpassing that of pure Ni (480 emu cm-3). Material characterizations and density functional theory calculations confirmed that the NiO nanoclusters embedded in the Ni matrix were primarily responsible for the high magnetization, as they were ferromagnetically coupled with Ni.
Article
Microscopy
Levi Tegg, Andrew J. Breen, Siyu Huang, Takanori Sato, Simon P. Ringer, Julie M. Cairney
Summary: The CAMECA Invizo 6000 atom probe microscope utilizes unique ion optics, including dual antiparallel deep ultraviolet lasers, a flat counter electrode, and various lenses, to enhance the field-of-view without compromising the mass resolving power. This study demonstrates the performance of the Invizo 6000 through three material case studies, using both air and vacuum-transfer between instruments. The results show that the Invizo 6000 significantly improves the field-of-view compared to a LEAP 4000 X Si and enhances specimen yield, particularly for difficult samples like oxides.
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.