Article
Energy & Fuels
Nor Anisa Arifin, Abd Halim Shamsuddin, Robert Steinberger-Wilckens
Summary: This study evaluates the influence of carbon deposition on the performance of Ni/YSZ and Ni/ScSZ solid oxide fuel cells operating in simulated biogas. The results show that carbon deposition affects performance, with Ni/ScSZ cells having higher carbon content but better performance than Ni/YSZ cells.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2021)
Article
Chemistry, Physical
Paul W. Hoffrogge, Daniel Schneider, Florian Wankmueller, Matthias Meffert, Dagmar Gerthsen, Andre Weber, Britta Nestler, Matthias Wieler
Summary: FIB-SEM measurements are used to study the as-processed Ni-YSZ solid oxide fuel cell (SOFC) anodes. Multiphase-field simulations are then conducted to investigate the microstructure and performance of the anodes under different operating conditions. The results are used to estimate anode performance and long-term stability using a transmission-line model (TLM).
JOURNAL OF POWER SOURCES
(2023)
Article
Chemistry, Physical
Mengmeng Wang, Naizhi Li, Zhongxu Wang, Chusheng Chen, Zhongliang Zhan
Summary: In this study, a dual-layer anode composed of Ni-Fe alloy layer and Ni-YSZ cermet layer was explored for solid oxide fuel cells (SOFCs). The results showed that the cell supported on the dual-layer anode with straight pore paths exhibited higher maximum power density and better oxidation-reduction cycle performance.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Electrochemistry
Qiangqiang Li, Dingxi Xue, Chongyang Feng, Xiongwen Zhang, Guojun Li
Summary: The performance degradation of solid oxide fuel cells is directly related to the damage and fracture of electrode microstructures. In this study, the fracture of anode microstructures is simulated using the phase field fracture method, and the effects of boundary constraints, thermal load, and the presence of Ni phase on the fracture are investigated.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2022)
Article
Electrochemistry
Jiashen Tian, Ryan J. Milcarek
Summary: The study found that the impact of siloxane on the anode of solid oxide fuel cells is irreversible, and carbon is also an important factor in siloxane contamination.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Chemistry, Physical
An He, Jiaming Gong, Junya Onishi, Naoki Shikazono
Summary: A numerical model is developed to optimize the 3D multiphase electrode microstructure for solid oxide fuel cells. The Ni-YSZ microstructure is deformed to maximize the total reaction current, and the multiphase level-set model and adjoint method are used for sensitivity analysis. A radius constraint is imposed to improve computational accuracy and manufacturability of the optimized microstructure.
Article
Electrochemistry
Yuanfeng Zou, Taicheng Lin, Yi Sun, Zhiyi Chen, Chengzhi Guan, Yang Li, San Ping Jiang, Na Ai, Kongfa Chen
Summary: For solid oxide fuel cells, an intimate anode/electrolyte interface can be created by applying anodic polarization current, leading to enhanced electrocatalytic activity and operating stability. The strong interfacial bonding induced by anodic polarization mitigates microstructure coarsening of Ni anodes, contributing to the enhanced stability.
ELECTROCHIMICA ACTA
(2021)
Article
Thermodynamics
Quanrong Fu, Zhiyi Li, Wei Wei, Fengxia Liu, Xiaofei Xu, Zhijun Liu
Summary: The study developed a fully coupled multi-field model to predict the performance degradation of SOFC due to Ni-particle coarsening, addressing the long-term stability and durability challenges. Results demonstrated that optimizing operating conditions and anode microstructure can enhance electrical performance and reduce degradation rate of SOFC.
ENERGY CONVERSION AND MANAGEMENT
(2021)
Article
Chemistry, Physical
Satoru Sakama, Merika Chanthanumataporn, Katsunori Hanamura
Summary: This study experimentally investigated the influence of electrochemical reactions on carbon deposition in solid oxide fuel cells using methane as fuel. The results showed that electrochemical reactions play an important role in suppressing carbon deposition by providing oxygen ions and increasing water concentration inside the anode. The amount of H2O supplied in fuel and the amount of oxygen ion produced by electrochemical reaction are the determining factors for carbon deposition.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Physical
Qingshan Li, Kunbin Kuang, Yuanna Sun, Yifeng Zheng, Qinglin Liu, Siew Hwa Chan, Hui Zhang, Weiguo Wang, Tingshuai Li, Junbo Wang
Summary: Deficient or non-linear hydrogen production is observed for the first time in large-scale steam electrolysis cells. Steam starvation affects the linearity of hydrogen production, with the Ni/NiO redox process playing a role in SOEC operations. The SOEC shows endurance to 10 hours of extreme polarization through electric conduction and oxygen vacancy transportation.
INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
(2022)
Article
Energy & Fuels
Jiashen Tian, Ryan J. Milcarek
Summary: The degradation of nickel-yttria stabilized zirconia (Ni-YSZ) anode in solid oxide fuel cells (SOFC) due to different types of siloxane contamination was investigated. It was found that cyclic siloxane, D4, caused more severe degradation with higher deposition on YSZ. The high adsorption and low desorption rates of cyclic siloxane were identified as the main factors contributing to the degradation.
FRONTIERS IN ENERGY RESEARCH
(2021)
Article
Chemistry, Physical
Yinkai Lei, Yueh-Lin Lee, William K. Epting, Jerry H. Mason, Tian-Le Cheng, Harry Abernathy, Gregory Hackett, You -Hai Wen
Summary: Ni redistribution in the hydrogen electrodes of solid oxide cells is an important degradation mechanism. This study investigates the interplay between Ni(OH)2 diffusion and Ni-YSZ wettability change, and identifies the driving force of Ni spreading/detachment and the factors affecting Ni redistribution. Two missing pieces in current theory of Ni redistribution are also identified.
JOURNAL OF POWER SOURCES
(2022)
Article
Chemistry, Applied
Dongxu Cui, Anna Sciazko, Yosuke Komatsu, Akiko Nakamura, Toru Hara, Shiliang Wu, Rui Xiao, Naoki Shikazono
Summary: In this study, two Ni/YSZ anodes with different volume ratios of Ni and YSZ were operated in dry methane under open circuit and polarized conditions. The reconstructed microstructures showed that the Ni surface near the active TPB did not have carbon deposition, while the remaining Ni surface away from the TPB exhibited severe carbon deposition. The results indicate a complex interplay between electrochemical steam generation and methane cracking on Ni surface.
JOURNAL OF ENERGY CHEMISTRY
(2023)
Article
Energy & Fuels
Shuodong Mi, Cheng Bao, Xin Lv
Summary: This article investigates the electrochemical co-oxidation mechanism of H2/CO hybrid fuel in solid oxide fuel cells (SOFC) through Reactive Force-Field (ReaxFF) reactive molecular dynamics (RMD) simulations. The study reveals that the presence of H2 enhances the conversion rate of CO, and oxygen vacancies have a significant effect on the oxidation of CO.
Article
Materials Science, Ceramics
Yonghyun Lim, Hojae Lee, Junghum Park, Young-Beom Kim
Summary: Solid oxide fuel cells (SOFCs) have the potential to become the next-generation energy conversion systems. However, the high processing temperature required for their multi-layer ceramic components has been a major barrier for commercialization. Researchers have developed a bi-layer sintering method that effectively lowers the sintering temperature of the electrolyte, leading to comparable cell performance with significantly reduced temperature.
CERAMICS INTERNATIONAL
(2022)
Article
Electrochemistry
Alex P. Cocco, Kyle N. Grew
Summary: The ATN model, originally developed for studying transport through microstructural networks, has been extended to electrokinetic flow. Channel-scale and network-scale models have been developed to describe electrokinetic flow efficiently in large, geometrically complex material structures. The automated algorithm for applying the theory to 3D images allows for rapid calculation of a structure's tortuosity factor.
JOURNAL OF ELECTROCHEMICAL ENERGY CONVERSION AND STORAGE
(2021)
Article
Electrochemistry
Alex P. Cocco, Kyle N. Grew
Summary: The analytical transport network (ATN) model is extended to investigate morphology and topology influence on coupled flow systems compared to uncoupled flows, using electrokinetic flow as an example system. The developed channel-scale model provides insights into the additional influence of morphology on coupled flows, compared to uncoupled flows, and is computationally less expensive. This modeling effort leads to the development of a computationally economical, network-scale model and associated algorithm for implementation to voxel-based three-dimensional images.
JOURNAL OF ELECTROCHEMICAL ENERGY CONVERSION AND STORAGE
(2021)
Article
Electrochemistry
Jacob N. Adams, George J. Nelson
Summary: High-capacity electrochemical alloying materials, such as tin and tin-based alloys, offer opportunities for advancement in lithium-ion batteries, but the destructive effects of volumetric expansion must be mitigated for sustained high capacity during extended cycling. Ex situ X-ray microtomography data on cycled Cu6Sn5 pellets revealed substantial microstructural changes during lithiation and delithiation, indicating the potential for volume expansion and structural collapse.
JOURNAL OF ELECTROCHEMICAL ENERGY CONVERSION AND STORAGE
(2021)
Review
Chemistry, Multidisciplinary
Fan Fu, Jia Li, Terry Chien-Jen Yang, Haoming Liang, Antonin Faes, Quentin Jeangros, Christophe Ballif, Yi Hou
Summary: This review focuses on the scientific and technological challenges of monolithic 2-terminal perovskite-silicon tandem solar cells, including factors limiting power conversion efficiency, pathways to achieve higher efficiency, and stability issues. Key areas of research to bring this technology from the lab to industrial production are highlighted.
ADVANCED MATERIALS
(2022)
Article
Electrochemistry
Hernando J. Gonzalez Malabet, Gabriel M. Cavalheiro, Takuto Iriyama, Austin Gabhart, George J. Nelson, Guangsheng Zhang
Summary: Prior research on Li-ion cells connected in parallel and cycled long term revealed that non-uniform temperature distribution led to non-uniform and accelerated degradation. Degradation mechanisms were elucidated through electrochemical and post-mortem analysis, pinpointing solid electrolyte interface (SEI) layer growth and lithium plating as main factors in the abrupt failure of the middle cell. The observation and quantitative analysis shed light on the performance and reliability impacts of non-uniform conditions within lithium-ion batteries.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2021)
Article
Materials Science, Coatings & Films
Caroline Hain, David Brown, Alexander Welsh, Krzysztof Wieczerzak, Robert Weiss, Johann Michler, Aicha Hessler-Wyser, Thomas Nelis
Summary: This study investigates the influence of different magnetron sputtering methods and microwave plasma-assisted techniques on the properties of high-hardness diamond-like carbon films, and it is found that microwave plasma can modify the morphology of the films but cannot increase the hardness.
SURFACE & COATINGS TECHNOLOGY
(2022)
Article
Nanoscience & Nanotechnology
Susmita Sarkar, Hernando J. Gonzalez-Malabet, Megan Flannagin, Alex L'Antigua, Pavel D. Shevchenko, George J. Nelson, Partha P. Mukherjee
Summary: In this study, we provide a comprehensive understanding of the electrochemical and mechanics coupling and electrode/electrolyte interfacial interactions in alloying Sn electrodes through multimodal analytics, including electrochemical, microscopy, and tomography analyses.
ACS APPLIED MATERIALS & INTERFACES
(2022)
Article
Polymer Science
Adam Barnett, John J. Karnes, Jibao Lu, Dale R. Major, James S. Oakdale, Kyle N. Grew, Joshua P. McClure, Valeria Molinero
Summary: Water content is a significant factor in the performance of ion-exchange membranes, with membranes absorbing water exponentially at high water activity. Molecular simulations reveal that the exponential increase in water uptake coincides with the glass to rubber transition of the membrane, and functionalization of the polymer with alkyl groups further contributes to its plasticization. The width of the water channels depends on the water to ions ratio in the polymer, not its ion-exchange capacity.
Article
Electrochemistry
Prehit Patel, Guangsheng Zhang, George J. J. Nelson
Summary: Increasing electrode thickness can enhance the energy density of lithium-ion batteries, but it also leads to transport limitations and lithium plating risks. This study explores potential improvements in conventional lithium-ion cells to achieve high energy density and fast charging capabilities. Using a 2D battery model, the impact of thick electrodes at different C-rates was examined. Various electrode modifications, including the addition of electrolyte channels, were simulated and compared in terms of performance and plating risk reduction. Dimensionless parameter analysis revealed the benefits and limitations of different electrode modification approaches.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Electrochemistry
Megan Flannagin, Baxter Barnes, William O'Donoghue, Jason Mayeur, Kavan Hazeli, George J. Nelson
Summary: Electrochemical changes were monitored by coupling external loading, electrochemical impedance spectroscopy (EIS), and distribution of relaxation times (DRT) analysis. The testing methods allowed for detailed observation of changes due to mechanical loading and distinguished responses between different cell geometries. Numerical modeling confirmed movement within individual cells and predicted locations with the most deformation based on applied external loading conditions.
JOURNAL OF THE ELECTROCHEMICAL SOCIETY
(2023)
Article
Materials Science, Coatings & Films
Jonathan Emanuel Thomet, Aman Kamlesh Singh, Melanie Nelly Roueche, Nils Toggwyler, Franz-Josef Haug, Gabriel Christmann, Sylvain Nicolay, Christophe Ballif, Nicolas Wyrsch, Aicha Hessler-Wyser, Mathieu Boccard
Summary: This paper reports on the fabrication of InGaN layers with various compositions using a low-temperature PECVD method and analyzes the influence of deposition parameters on the resulting films. The growth rate and In content are found to affect the crystallinity and optical properties of the films.
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
(2022)
Article
Energy & Fuels
Loic Tous, Jonathan Govaert, Samuel Harrison, Carolyn Carriere, Vincent Barth, Valentin Giglia, Florian Buchholz, Ning Chen, Andreas Halm, Antonin Faes, Gizem Nogay, Hugo Quest, Torsten Roessler, Tobias Fellmeth, Dirk Reinwand, Hannah Stolzenburg, Florian Schindler, Max Mittag, Arnaud Morlier, Matevz Bokalic, Kristijan Brecl, Miha Kikelj, Marko Topic, Josco Kester, Stefan Wendlandt, Marco Galiazzo, Alessandro Voltan, Giuseppe Galbiati, Marc Estruga Ortiga, Frank Torregrosa, Michael Grimm, Julius Denafas, Tadas Radavicius, Povilas Lukinskas, Tuukka Savisalo, Thomas Regrettier, Ivan Gordon
Summary: The EU c-Si PV manufacturing industry has faced strong competition and needs to focus on high performing technologies, sustainability, and differentiated module designs. The HighLite project aims to bring advanced PV module designs to higher technology readiness levels and has achieved promising results so far.
PROGRESS IN PHOTOVOLTAICS
(2023)
Article
Energy & Fuels
S. Libraro, M. Lehmann, J. J. Diaz Leon, C. Allebe, A. Descoeudres, A. Ingenito, C. Ballif, A. Hessler-Wyser, F-J Haug
Summary: Replacing silver metallization with earth-abundant materials is an important step for sustainable growth of photovoltaics. In this study, fire-through processes using aluminum as the metallization material for solar cells were investigated. It was found that increasing the nitrogen content of the silicon nitride can reduce aluminum penetration depth. The mechanisms behind metal-induced passivation degradation were also investigated and possible mitigation strategies were identified using an adapted SiOx/SiCx stack for tunnel oxide passivating contacts.
SOLAR ENERGY MATERIALS AND SOLAR CELLS
(2023)
Article
Materials Science, Coatings & Films
Caroline Hain, Peter Schweizer, Patrick Sturm, Aurelio Borzi, Jonathan E. Thomet, Johann Michler, Aicha Hessler-Wyser, Thomas Nelis
Summary: This study focuses on the fabrication of InN thin films at low temperature using microwave plasma-assisted reactive high power impulse magnetron sputtering (MAR-HiPIMS). The effects of microwave plasma on the HiPIMS discharge process were investigated through in situ diagnostics. InN films were deposited using both standard reactive HiPIMS and MAR-HiPIMS methods, and their properties were characterized. Results showed that the microwave plasma facilitated the dissociation/activation of nitrogen species and provided seed electrons to the plasma. The MAR-HiPIMS film exhibited stoichiometry, texturing, and desirable electrical properties.
SURFACE & COATINGS TECHNOLOGY
(2023)
Article
Instruments & Instrumentation
Adrian Brugger, Hassina Z. Bilheux, Jiao Y. Y. Lin, George J. Nelson, Andrew M. Kiss, Jonathan Morris, Matthew J. Connolly, Alexander M. Long, Anton S. Tremsin, Andrea Strzelec, Mark H. Anderson, Robert Agasie, Charles E. A. Finney, Martin L. Wissink, Mija H. Hubler, Roland J. -M. Pellenq, Claire E. White, Brent J. Heuser, Aaron E. Craft, Jason M. Harp, Chuting Tan, Kathryn Morris, Ann Junghans, Sanna Sevanto, Jeffrey M. Warren, Fernando Esteban L. Florez, Alexandru S. Biris, Maria Cekanova, Nikolay Kardjilov, Burkhard Schillinger, Matthew J. Frost, Sven C. Vogel
Summary: The Oak Ridge National Laboratory plans to build the Second Target Station at the Spallation Neutron Source, which will feature a suite of novel instruments complementing the capabilities of the existing First Target Station. Among the first eight instruments to be commissioned at the Second Target Station is (CUPID)-D-2, a neutron imaging beamline designed for various scientific applications. It utilizes a high flux of wavelength-separated cold neutrons to perform real-time neutron grating interferometry and Bragg edge imaging across a broad range of length and time scales.
REVIEW OF SCIENTIFIC INSTRUMENTS
(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.
