Article
Multidisciplinary Sciences
Bjorn Miksch, Andrej Pustogow, Mojtaba Javaheri Rahim, Andrey A. Bardin, Kazushi Kanoda, John A. Schlueter, Ralph Hubner, Marc Scheffler, Martin Dressel
Summary: The study investigated the κ-(BEDT-TTF)2Cu-2(CN)3 using multifrequency electron spin resonance (ESR) down to millikelvin temperatures, revealing a rapid decrease in spin susceptibility at 6 kelvin, suggesting the formation of a valence bond solid ground state. It also identified the dominant contribution of impurities to the ESR response when intrinsic spins form singlets, highlighting the pivotal role of defects in the low-energy properties of quantum spin systems without magnetic order.
Article
Materials Science, Multidisciplinary
Lorenz Romaner, Tapaswani Pradhan, Anastasiia Kholtobina, Ralf Drautz, Matous Mrovec
Summary: This study provides a detailed comparative analysis of the M111 dislocation in five bcc transition metals, revealing significant variations in Peierls barriers and stresses among different metals. Tungsten and Molybdenum exhibit sizable barriers, while Niobium, Tantalum, and Iron have comparably small barriers. The predictions are consistent with internal friction measurements and offer new insights into the plasticity of bcc metals.
Article
Construction & Building Technology
Yujia Lu, Suwen Chen, Xiao Shao
Summary: This study investigates the effects of temperature, time, and strain rate on the shear small-strain modulus of the transparent ionomer material SG from a practical application perspective. The time-temperature dependent equations of shear modulus are applied to numerical simulation of a long-term loading test, providing valuable insights for the behavior of laminated glass with SG interlayers.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Materials Science, Multidisciplinary
S. Imajo, A. Miyake, R. Kurihara, M. Tokunaga, K. Kindo, S. Horiuchi, F. Kagawa
Summary: The one-dimensional organic salt TTF-QBr(3)I demonstrates a ferroelectric spin-Peierls state in a quantum critical regime, leading to the emergence of spin solitons as topological defects. Strong quantum fluctuations near a quantum critical point enable the high mobility of solitons even at low temperatures.
Article
Materials Science, Multidisciplinary
Ivo Heinmaa, Riho Rasta, Harlyn J. Silverstein, Christopher R. Wiebe, Raivo Stern
Summary: NaTiSi2O6 is an exemplary compound that undergoes an orbital assisted spin-Peierls phase transition at its critical temperature. Si-29 and Na-23 nuclear magnetic resonance measurements provide valuable insights into the compound's behavior at different temperatures. These findings are significant for understanding the properties of NaTiSi2O6.
Article
Polymer Science
Junyi Zhou, Ulrich Heisserer, Phillip W. Duke, Paul T. Curtis, John Morton, Vito L. Tagarielli
Summary: A new test technique was employed to measure the tensile response of different materials at various strain rates and temperatures. The study found that the tensile properties of Kevlar and Dyneema are sensitive to temperature and strain rate, and can be estimated at high strain rates using time-temperature equivalence.
Article
Chemistry, Physical
Keisho Umesaki, Kei Odai
Summary: The transfer matrix (TM) method was used to calculate the transmission probability (TP) and evaluate the tunneling factors in proton transfer reactions. TPs for guanine-cytosine base pair reactions were calculated by the TM method and compared with analytical solutions, showing small errors. The TM method was then applied to evaluate tunneling factors for guanine-thymine (G-T) and adenine-cytosine (A-C) mispair reactions, revealing significant contributions of shoulder peaks in the G-T reaction and little contribution in the A-C reaction, which are difficult to obtain using methods like Wigner's tunneling factor.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Materials Science, Multidisciplinary
Zhongpeng Qi, Liu He, Fang Wang, Jin Wang, Junliang Cheng, Guiqiu Xie, Xiangguo Zeng
Summary: The study investigates the influence of temperature and strain rate on tensile stress reversal in dynamic damage of single-crystal nickel titanium (NiTi) alloy. It is observed that at temperatures between 2350 and 2700 K, a double-peak structure in the stress reversal curve occurs, with the second reversal dependent on void nucleation. The number of peaks changes from two to one as the strain rate increases.
MECHANICS OF MATERIALS
(2022)
Article
Multidisciplinary Sciences
Brook J. Hocking, Helen S. Ansell, Randall D. Kamien, Thomas Machon
Summary: By analyzing the topology of the ground state manifolds (GSMs) of density wave systems, it has been found that dislocations split into disclinations, and these disclinations are constrained to sit at specific phase values, resulting in an energy barrier to dislocation glide.
PROCEEDINGS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
(2022)
Article
Physics, Multidisciplinary
Xuedong Xie, Dongjing Lin, Li Zhu, Qiyuan Li, Junyu Zong, Wang Chen, Qinghao Meng, Qichao Tian, Shao-Chun Li, Xiaoxiang Xi, Can Wang, Yi Zhang
Summary: The study reveals that two stable CDW states can coexist on the NbSe2/BLG surface, and the charge transfer from substrates influences the configurations of the Fermi surface differently. Temperature-dependent Raman experiments suggest that the electron-phonon coupling dominates the CDW phase transition in monolayer NbSe2.
CHINESE PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Gang Luo, Chunbo Wu, Kailong Xu, Lulu Liu, Wei Chen
Summary: The study focused on the compression properties of TDE86 epoxy resin at different temperatures and strain rates, revealing that the elastic modulus, yield stress, and yield strain of the epoxy increase with strain rate but decrease with temperature. The dynamic stress-strain curve of the epoxy can be divided into four stages, and there is no distinct relationship between yield strain and logarithmic strain rate at high strain rates.
MECHANICS OF MATERIALS
(2021)
Article
Multidisciplinary Sciences
Hong-Ze Xu, Shun-Yao Zhang, Guang-Can Guo, Ming Gong
Summary: This study identifies the exact dimer phase and three different ferromagnetic phases in the extended XYZ model, with boundaries between them exhibiting interesting properties related to translational symmetry and Z(2) symmetry breaking. The boundaries between the ferromagnetic phases also exhibit critical behavior with a central charge of c = 1 for free fermions. This research sheds light on the effects of anisotropy in one-dimensional magnets, providing insights into experimental signatures and resolving discrepancies between theoretical predictions and experimental results.
SCIENTIFIC REPORTS
(2021)
Article
Materials Science, Multidisciplinary
Wasim Raja Mondal, Egor Evlyukhin, Sebastian A. Howard, Galo J. Paez, Hanjong Paik, Darrell G. Schlom, Louis F. J. Piper, Wei-Cheng Lee
Summary: The investigation focused on the vibrational properties of VO2, specifically the low-temperature M1 phase, through first-principles calculations and Raman spectroscopy. The challenging task involved reproducing the vibrational characteristics of the M1 phase through phonon calculations, while experimental results showed a noticeable effect of phase transition on Raman spectra.
Article
Physics, Applied
K. Nishikawa, S. Takakura, M. Nakatake, M. Yoshimura, Y. Watanabe
Summary: Vanadium dioxide (VO2) demonstrates a metal-insulator phase transition with thermal hysteresis at around 70°C. The transition temperatures, T-IMT and T-MIT, cause significant changes in reflectivity and electrical resistivity of VO2 during heating and cooling. By irradiating Ar+ on the surface of VO2 nanostructures, the T-IMT and T-MIT can be modified with varying Ar+ irradiation doses. Ar+ irradiation decreases the thermal hysteresis width by reducing the V atoms at the outermost surface state of VO2.
JOURNAL OF APPLIED PHYSICS
(2023)
Article
Chemistry, Physical
Peinan Zhou, Yifei Wang, Shamima Nasreen, Yang Cao
Summary: The study revealed that aromatic polymers have lower barrier heights, and the chemical structure plays a crucial role in determining barrier heights. Additionally, aromatic polymers with higher glass transition temperatures have lower injection barrier heights.
SURFACES AND INTERFACES
(2021)
Article
Materials Science, Multidisciplinary
Jan Fikar, Roman Groger, Robin Schaeublin
JOURNAL OF NUCLEAR MATERIALS
(2017)
Article
Instruments & Instrumentation
Jan Fikar, Roman Groeger, Robin Schaeublin
NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
(2017)
Article
Materials Science, Multidisciplinary
R. Groger, V. Vitek, T. Lookman
PHYSICAL REVIEW MATERIALS
(2017)
Article
Nanoscience & Nanotechnology
Roman Groger, Zdenek Chlup, Tereza Kubenova
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2018)
Article
Materials Science, Multidisciplinary
R. Groger, Z. Chlup, I. Kubena, T. Kruml
PHILOSOPHICAL MAGAZINE
(2018)
Review
Materials Science, Multidisciplinary
Roman Groger, Zdenek Chlup, Tereza Kubenova, Ivo Kubena
JOURNAL OF MATERIALS RESEARCH
(2019)
Article
Materials Science, Multidisciplinary
Roman Groger, Vaclav Vitek
COMPUTATIONAL MATERIALS SCIENCE
(2019)
Article
Engineering, Mechanical
Roman Groger, Vaclav Vitek
INTERNATIONAL JOURNAL OF PLASTICITY
(2020)
Article
Materials Science, Multidisciplinary
R. Groger, V. Vitek, A. Dlouhy
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2020)
Article
Materials Science, Multidisciplinary
Zdenek Antos, Petr Vacek, Roman Groger
COMPUTATIONAL MATERIALS SCIENCE
(2020)
Article
Materials Science, Multidisciplinary
Roman Groger, Jiri Sremr, Jana Vydrova
Summary: The simplified models of thermally activated dislocation glide serve as an important connection between atomic-level studies of isolated dislocations and macroscopic thermodynamic properties of materials. By minimizing the activation enthalpy and solving for the shape of the dislocation line, a unique activated state of the dislocation can be defined, showing that the shape of the dislocation changes with applied stress to maintain the state of minimum activation enthalpy.
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2021)
Article
Physics, Applied
Petr Vacek, Martin Frentrup, Lok Yi Lee, Fabien C. P. Massabuau, Menno J. Kappers, David J. Wallis, Roman Groeger, Rachel A. Oliver
Summary: The defect structure of zincblende GaN nucleation layers grown on 3C-SiC/Si (001) was investigated, which includes perfect dislocations, partial dislocations, and stacking faults. These defects, especially perfect and partial dislocations, help relieve the compressive lattice mismatch strain in GaN layers. The stacking faults in the layers are mainly bounded by 30 degrees Shockley partial dislocations and occasionally by Lomer-Cottrell partial dislocations, originating from the dissociation of perfect dislocations or direct nucleation of partial dislocations loops from the surface.
JOURNAL OF APPLIED PHYSICS
(2021)
Article
Engineering, Mechanical
Roman Groger
Summary: This study demonstrates the invariance of yield criteria in determining plastic deformation onset in crystalline materials under inversion symmetry, as well as the specific yield criterion for non-Schmid materials. The model is applied to body-centered cubic and hexagonal close-packed metals to show the significance of non-Schmid stress terms in predicting yielding onset. In the special case where all non-Schmid stresses vanish, the model simplifies to Tresca's maximum shear stress theory.
INTERNATIONAL JOURNAL OF PLASTICITY
(2021)
Article
Materials Science, Multidisciplinary
Roman Groger
Summary: A study has found that the phenomenon of anomalous slip in transition metals is closely related to the stability of screw junctions between dislocations. In most bcc metals, these junctions do not break under stress and the dislocations can only move on common crystal planes. However, in alkali metals, tantalum, and iron, the application of stress causes the dislocations to unzip and further glide on predicted planes. These results provide an explanation for the experimentally observed anomalous slip and suggest a reason for its increased propensity in later stages of plastic deformation.
MODELLING AND SIMULATION IN MATERIALS SCIENCE AND ENGINEERING
(2022)
Article
Nanoscience & Nanotechnology
Zachary T. Kloenne, Jean-Philippe Couzinie, Milan Heczko, Roman Groger, Gopal B. Viswanathan, William A. T. Clark, Hamish L. Fraser
Summary: A refined microstructure consisting of bcc precipitates embedded in an ordered B2 matrix has been observed in the refractory high entropy alloy AlMo0.5NbTa0.5TiZr, resembling an inverted superalloy-like micro-structure. Coarsening of the microstructure occurs after aging, resulting in a faceted interface. Misfit dislocations at the interface were observed on the {110} interface plane, extending into the bcc phase, and no lattice invariant deformation normal to the primary {110} planes was observed, indicating a pure expansion transformation between the B2 and bcc phases.
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.