Article
Nanoscience & Nanotechnology
X. X. Dong, Y. F. Shen, W. Y. Xue, N. Jia
Summary: This study investigates the microstructure and mechanical properties of 0.56 wt % C TRIP steel under various deformation conditions, revealing that the steel exhibits excellent mechanical properties at 300 degrees C mainly due to the combined effects of TRIP and precipitation strengthening.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
Yuming Zou, Hua Ding, Zhengyou Tang
Summary: The increase in carbon content enhances the strength and ductility of medium Mn steels, promoting the diffusion of C and Mn atoms, increasing the stability and volume fraction of austenite, strengthening the TRIP effect, thus improving the work hardening and ductility of the material.
Article
Nanoscience & Nanotechnology
T. W. J. Kwok, P. Gong, R. Rose, D. Dye
Summary: Two different microstructures of medium Mn steel were obtained through different approaches in hot rolling mill, showing a simultaneous twinning induced plasticity and transformation induced plasticity (TWIP + TRIP) mechanism. However, twinning contributed relatively little to the strength of the alloy, mainly due to the small initial slip lengths that reduced the opportunity for grain work hardening.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Engineering, Civil
Aleksandra Kozlowska, Adam Grajcar, Aleksandra Janik, Krzysztof Radwanski, Ulrich Krupp, Krzysztof Matus, Mateusz Morawiec
Summary: Advanced medium-Mn sheet steels offer a cost-effective and lightweight solution for automotive parts, with improved safety and optimized environmental performance. The mechanical stability of retained austenite plays a crucial role in enhancing the strength-ductility balance, while benefiting from manganese addition in the range of 3-5%. Temperature dependence and stimulation by manganese addition were observed in the pronounced stability of retained austenite.
ARCHIVES OF CIVIL AND MECHANICAL ENGINEERING
(2021)
Article
Nanoscience & Nanotechnology
Baojia Hu, Qinyuan Zheng, Yi Lu, Chunni Jia, Tian Liang, Chengwu Zheng, Dianzhong Li
Summary: A novel processing route of intercritical Mn partitioning is proposed to stabilize the reverted austenite in a medium Mn steel, which consists of a core in low Mn content and a shell in relatively high Mn content. This distinctive microstructure allows for more retained austenite and excellent mechanical properties.
SCRIPTA MATERIALIA
(2023)
Article
Metallurgy & Metallurgical Engineering
Geng Tian, Zhen Li, Shun Yao, Rongjian Qie, Yifu Cui, Aimin Zhao
Summary: A high-strength medium Mn steel is produced through intercritical annealing and quenching processes. The steel composition used in the experiment is Fe-0.2C-8.0Mn-1.6Si-1.3Al (wt%). The resulting microstructures consist of ferrite/martensite and retained austenite phases. The carbon and manganese partitioning behavior during the intercritical annealing process is simulated using DICTRA. The sample annealed at 700 degrees C for 10 minutes exhibits the best mechanical properties, with a strength and elongation product of 47.25 GPa%.
STEEL RESEARCH INTERNATIONAL
(2023)
Article
Nanoscience & Nanotechnology
Adam Grajcar, Adam Skowronek, Krzysztof Radwanski
Summary: The research shows that controlling the microstructure and size of retained austenite in multiphase steels can affect their mechanical properties, and it is necessary to produce dispersed retained austenite of different sizes for the TRIP effect instead of striving for maximum fragmentation.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Metallurgy & Metallurgical Engineering
Bao-Jia Hu, Qin-Yuan Zheng, Chun-Ni Jia, Peng Liu, Yi-Kun Luan, Cheng-Wu Zheng, Dian-Zhong Li
Summary: By introducing precursor microstructure prior to normal austenite reverted transformation (ART) annealing, the intercritical annealing path in a 0.2C-5Mn medium-Mn steel can be optimized. Pre-annealing at high intercritical temperatures promotes precipitation and dissolution of carbides, accelerates austenite reversion, and assists in the formation of RA, leading to excellent strength-elongation balance in heat-treated samples.
ACTA METALLURGICA SINICA-ENGLISH LETTERS
(2022)
Article
Materials Science, Multidisciplinary
Lei Liu, Cainian Jing, Borong Shan, Zhihao Zhang, Shunzhi Zhao, Tao Lin, Jingrui Zhao
Summary: The effects of different annealing temperatures on the microstructure, C-element diffusion, and mechanical properties of medium-Mn steel using the one-step quenching and partitioning (Q&P) process combined with the annealing process were systematically studied. The results showed that the annealed test steel at 670 degrees Celsius exhibited excellent comprehensive mechanical properties.
MATERIALS TODAY COMMUNICATIONS
(2022)
Article
Materials Science, Multidisciplinary
Tao Lin, Yan Feng, Lei Liu, Cainian Jing, Zhonglin Wu, Zhaotong Li, Jingrui Zhao
Summary: The effect of partitioning temperature on the microstructure and mechanical properties of a hot-rolled medium manganese Q&P steel was studied. It was found that as the partition temperature increased, the fractions and size of the fresh massive martensite increased, while the initial lamellar martensite coarsened and decreased in amount. The amounts of lath-like retained austenite decreased, while bulky austenite increased. The steel partitioned at 260 degrees C showed the best comprehensive mechanical properties with a combination of high tensile strength, elongation, and good stability.
Article
Materials Science, Multidisciplinary
B. B. He, S. Pan
Summary: Increasing austenite stability through Mn alloying effectively suppresses martensitic transformation in medium Mn steel, resulting in higher nanohardness for large austenite grains. Despite grain boundary strengthening, the nanohardness of ferrite remains lower than that of austenite grains. The intrinsic nanohardness of austenite found in this study can provide valuable input parameters for modeling high strength steels with retained austenite.
MATERIALS CHARACTERIZATION
(2021)
Article
Metallurgy & Metallurgical Engineering
Ying Dong, Min Qi, Yu Du, Hongyan Wu, Xiuhua Gao, Linxiu Du
Summary: The effect of retained austenite stability on the yield point elongation phenomenon in a hot-rolled and intercritically annealed medium-Mn steel is investigated. It is found that the suppression of shear phase transition and the acceleration of intercritical austenite nucleation and growth contribute to refined martensite laths with high dislocation density. The occurrence of yield point elongation is attributed to the storage and transfer of stress in the retained austenite with higher stability.
STEEL RESEARCH INTERNATIONAL
(2022)
Article
Nanoscience & Nanotechnology
P. Kantanen, S. Anttila, P. Karjalainen, R. Latypova, M. Somani, A. Kaijalainen, J. Komi
Summary: The processing conditions to achieve the desired tensile strength and minimum retained austenite fraction in hot-rolled 3-4%Mn medium Mn steels were investigated using quenching and partitioning (QP) and austenite reverse transformation (ART) treatments. The results showed that both processes can achieve relatively high fractions of austenite, with comparable results to those predicted by thermodynamic equilibrium.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2022)
Article
Chemistry, Physical
Simon Vander Vennet, Silvia Leitner, Vsevolod Razumovskiy, Werner Ecker, Tom Depover, Kim Verbeken
Summary: This study investigates the effect of a constant load on hydrogen diffusion through a Q&P steel containing metastable retained austenite. The results show that hydrogen diffusion is delayed under all stressed conditions, even at stresses in the elastic regime, with the delay increasing with the applied load. Thermal desorption spectroscopy reveals the presence of a high temperature peak in the samples tested under load, indicating hydrogen effusion and release due to the transformation of retained austenite.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2023)
Article
Materials Science, Multidisciplinary
Maribel Arribas, Eider Del Molino, Teresa Gutierrez, Artem Arlazarov, David Martin, Daniele De Caro, Sudhindra Ayenampudi, Maria J. Santofimia
Summary: In this study, a medium Mn-Ni steel was treated through Quenching and Partitioning (Q&P) with different quenching temperatures (QT) and partitioning times (Pt) to investigate their influence on the stabilization of austenite and mechanical properties. It was found that the quenching temperature had a significant influence on the results. The Q&P cycle with quenching to room temperature and a high partitioning temperature produced a steel with a high retained austenite (RA) volume fraction and exceptional strength-ductility balance.
Article
Materials Science, Multidisciplinary
Yuhai Qu, Xiaoming Sun, Wanyuan Gui, Runguang Li, Zhihua Nie, Zhiyong Gao, Wei Cai, Yang Ren, Yandong Wang, Daoyong Cong
Summary: Magnetic-field-induced first-order magnetostructural transition (MFI-FOMST) has various magnetoresponsive effects, but practical applications have been limited by the high critical field. In this study, we achieved complete and reversible MFI-FOMST under a low field of 1.5 T in a prototype shape memory alloy. This was made possible by enlarging the distance between Curie transition and magnetostructural transition and manipulating the geometric compatibility between phases. The low critical field provides opportunities for low-field-induced large reversible magnetoresponsive effects and practical applications of MSMAs.
Article
Chemistry, Physical
Tiancheng Li, Haiyang Chen, Zaifeng Zhou, Shilei Li, Yan-Dong Wang
Summary: A high-entropy alloy with superior strength and ductility was designed using a core-shell structure and adjusting the structural gradient to achieve synergistic strength-ductility effects.
Article
Nanoscience & Nanotechnology
Zhenchang Hou, Zhihua Nie, Zhichao Liu, Jun Gao, Fang Hao, Chengwen Tan, Yandong Wang
Summary: An as-cast Ni81W10Al9 alloy with remarkable mechanical properties was developed by adjusting the alloying element with appropriate enthalpy of mixing. The yield strength of the alloy reached about 640 MPa, which is approximately three times higher than its Al-free counterpart. Extensive L12 phase nanoscale precipitations were generated in the alloy, providing strong strengthening effects by blocking dislocation sliding.
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2023)
Article
Physics, Fluids & Plasmas
Xiuxuan Duan, Shuoxue Jin, Yamin Song, Yanli Wang, Yi Xiong, Weiping Zhang, Shilei Li, Xingzhong Cao
Summary: The effect of pre-irradiation defects on helium trapping and diffusion behaviors was analyzed using a slow positron beam. Microscopic defects were observed in Si ion irradiated specimens. Low energy helium atoms could diffuse into deeper regions in metals without displacement damage. During the diffusion process, the helium atoms would be trapped by the Si-ion pre-irradiation defects. The formation of He-vacancy complexes affected the annihilation of positrons with electrons, leading to decreased S parameters. Shallow defects induced by 300 keV irradiation hindered helium diffusion more effectively than deep defects induced by 6 MeV irradiation. Therefore, pre-introduced defects can effectively trap helium atoms and hinder their diffusion.
Article
Nanoscience & Nanotechnology
Yan-Dong Wang, Youkang Wang, Shilei Li, Runguang Li
Summary: High-energy X-ray diffraction and X-ray microdiffraction techniques are powerful tools for characterizing localized stress/microstructural gradients in heterostructured materials, and have been used to study their mechanical heterogeneity.
SCRIPTA MATERIALIA
(2023)
Review
Materials Science, Multidisciplinary
Jie Yan, Weixia Dong, Peijian Shi, Tianyi Li, Wenjun Liu, Yan-Dong Wang, Xun-Li Wang, Yuntian Zhu, Yang Ren
Summary: Heterostructured materials (HSMs) have the potential to break the strength-ductility tradeoff, but understanding their deformation physics and strengthening mechanisms is challenging due to their complex structures. Synchrotron x-rays provide powerful techniques for studying HSMs at different length scales. This article introduces in situ high-energy x-ray diffraction and Laue x-ray microdiffraction techniques and their application in studying stress partitioning, phase transformations, and deformation microstructures in HSMs.
Review
Materials Science, Multidisciplinary
H. A. I. Y. A. N. G. CHEN, X. I. A. N. G. Y. U. ZHANG, Y. U. R. O. N. G. NIU, D. A. O. Y. O. N. G. CONG, Y. A. N. G. REN, YAN-DONG WANG
Summary: In the field of structural materials, creating a heterogeneous structure has been proven to effectively enhance comprehensive mechanical properties. The improvement of mechanical properties is essential for metallic functional materials known as shape memory alloys (SMAs) to exhibit associated functional responses. The microstructural heterogeneity of SMAs plays a crucial role in resisting irreversible deformation and regulating the nature of martensitic transformation. This review focuses on recent advances in SMAs reinforced by heterogeneous microstructures spanning various length scales, which exhibit favorable mechanical and functional properties under external stimuli. These findings provide insight into the potential for programmatically triggering novel and specific functionalities in SMAs through the design of hierarchical microstructures.
Article
Materials Science, Multidisciplinary
Bin Hu, Guohui Shen, Zheng Wang, Shilei Li, Yandong Wang, Haiwen Luo
Summary: We have developed a new type of ultrastrong medium Mn steel with a density reduced to 7.39 g cm-3. This steel has a unique tri-phase microstructure consisting of a hierarchical martensitic matrix, ultra-fine-retained austenite grains, and compressed and {200} oriented 8-ferrite lamellas. The high Al and Si contents in the alloying contribute to the formation of 8-ferrite lamellas and the reduction of density. Through in-situ synchrotron-based high-energy X-ray diffraction examinations, it is revealed that the residual compressive stress in 8-ferrite, dislocation multiplication in all three phases, and the gamma-to-alpha' transformation contribute to the remarkable work hardening increment. This study facilitates the development of novel strategies for fabricating ultrastrong but light steels.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Zhongguo Yang, Fusheng Li, Jing Yao, Shilei Li, Yanli Wang
Summary: In our research, we discovered the presence of zeta-hydride as an intermediate phase in the alpha-Zr/8-hydride interface in electropolished Zircaloy-4 TEM lamella. High-resolution transmission electron microscopy confirmed the existence of zeta-hydride in the alpha-8 interface with a specific orientation relationship. This finding suggests that the formation of zeta-hydride as an intermediate phase in the alpha-8 interface can reduce local interphase stress.
Article
Nanoscience & Nanotechnology
Delun Gong, Haoliang Wang, Qiushuang Wang, Shujun Li, Kun Lin, Yandong Wang, Rui Yang, Yulin Hao
Summary: The temperature coefficient of elastic modulus in titanium alloys can be positive or negative depending on the phase present. By aging treatment in a Ti-Nb-based alloy, the coefficient can be tuned from positive to negative through a phase transition process. This study shows that the coefficient can be continuously adjusted by a compositionally-modulated dual-phase microstructure induced by spinodal decomposition. These findings provide a new strategy for achieving Elinvar effect through heat treatments.
SCRIPTA MATERIALIA
(2023)
Article
Materials Science, Multidisciplinary
Minghe Zhang, Lihui Sun, Yaliang Liu, Yunli Feng, Ning Xu, Haiyang Chen, Yan-Dong Wang
Summary: A novel Cu-added medium-Mn steel was designed and subjected to intercritical annealing, which resulted in increased yield strength and decreased elongation. The addition of Cu led to the precipitation of Cu-rich nanoparticles, which contributed to the discrepancy in yield strength between ferrite and austenite.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
D. L. Gong, H. L. Wang, S. H. Hao, P. Liu, X. Yang, Y. N. Jiang, W. J. Wang, K. Lin, B. Li, K. Du, Y. D. Wang, R. Yang, Y. L. Hao
Summary: By adjusting the phase decomposition in Ti-Nb-based titanium alloy, the Elinvar effect in a wide temperature range and a high strength-to-modulus ratio can be achieved. The aged alloy has an almost constant elastic modulus with temperature, as well as high yield strength, good ductility, and a high elastic admissible strain. This study provides a new strategy to extend the temperature range of Elinvar and enhance strength by tuning the crystal ordering of decomposition alloys.
JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
T. Yin, Z. W. Zhu, J. Mu, J. Wang, R. G. Li, Y. Ren, Y. D. Wang, Y. Li
Summary: In this study, in-situ high-energy X-ray diffraction and post-mortem transmission electron microscopy were used to investigate the deformation mechanism of a Ti-42Zr-13Nb alloy exhibiting two-stage yielding behavior under tension. It was found that the first yielding stage is influenced by the reorientation of pre-existing α phase and the preferential induction of α variants during martensitic transformation. The second yielding stage is mainly dominated by the reorientation of stress-induced α martensite. These findings provide new insights into the reorientation scenarios and work-hardening behavior of Ti-based shape memory alloys.
MATERIALS CHARACTERIZATION
(2023)
Article
Nanoscience & Nanotechnology
Zhiran Yan, Kiranbabu Srikakulapu, Yi Gao, Hailong Qin, Yi Rong, Zhongnan Bi, Qingge Xie, Ke An, Yan-dong Wang, Qing Tan
Summary: The ?′-size effect on microstructure and grain rotation in a polycrystalline Ni-based superalloy during tensile deformation was investigated using in-situ neutron diffraction. Diffraction profile analysis revealed dislocation shearing and Orowan dislocation bypassing in alloys with fine and coarse ?′, respectively. The coarse ?' specimen exhibited higher strain hardening due to accelerated dislocation accumulation, and also resulted in weaker fiber texture components.
SCRIPTA MATERIALIA
(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.
