Article
Chemistry, Physical
Iztok Naglic, Blaz Leskovar, Zoran Samardzija, Bostjan Markoli
Summary: This study investigated the influence of gallium addition on the phases formed in Al-Mn alloys during casting, revealing that an increase in gallium content led to the formation of IQCs and DQCs in the alloys. Microanalysis showed that IQCs contained more gallium and less manganese compared to DQCs.
Article
Materials Science, Multidisciplinary
Min Qi, Yingjie Ma, Jie Yang, Yandi Jia, Hanbo Weng, Sensen Huang, Ruixue Zhang, Jianke Qiu, Jiafeng Lei, Rui Yang
Summary: This study investigated the microtexture evolution of alpha in alpha + beta titanium alloys with different Mo content during thermomechanical processing. The results show that the addition of Mo element significantly weakens the microtexture of the prior alpha colony in Ti-6Al-2Sn-4Zr-6Mo (Ti6246) alloy. The study demonstrates the effect of Mo content on the microtexture evolution during thermo-mechanical processing.
MATERIALS CHARACTERIZATION
(2022)
Article
Chemistry, Physical
Nadezhda V. Vladimirova, Alexander S. Frolov, Jaime Sanchez-Barriga, Oliver J. Clark, Fumihiko Matsui, Dmitry Yu Usachov, Matthias Muntwiler, Carolien Callaert, Joke Hadermann, Vera S. Neudachina, Marina E. Tamm, Lada Yashina
Summary: Occupancy of different structural positions in a crystal lattice plays a key role in material properties. X-ray Photoelectron Diffraction (XPD) is a surface science structural method that can be used for occupancy analysis. By studying Sb2(Te1-xSex)3 mixed crystals, we found that XPD data showed excellent agreement with the reference method. We also discovered significant differences in anion occupancy between the surface and bulk.
SURFACES AND INTERFACES
(2023)
Article
Materials Science, Multidisciplinary
Daniela Marusakova, Cinthia Antunes Correa, Claudia Aparicio, Ondrej Libera, Jan Berka, Monika Vilemova, Petra Gavelova
Summary: Nickel-based alloys, particularly Inconel 738, were tested in high-temperature gas reactor conditions to examine their performance in the primary helium coolant. Precision casting with different amounts of revert material was used to manufacture the alloys, and scanning electron microscopy and hardness testing were conducted to characterize the materials. The results showed that both revert materials exhibited similar corrosion resistance and mechanical properties in HTGR conditions.
Article
Materials Science, Multidisciplinary
Haotian Guan, Lingguo Zeng, Zhijun Li, Linjiang Chai, Yufan Zhu, Yueyuan Wang, Qin Huang, Ke Chen, Liang-yu Chen, Ning Guo
Summary: In this study, detailed microstructural characteristics of a Zr702 sheet subjected to beta air cooling and subsequent 15% rolling were characterized. Results showed that both cooling and rolling processes significantly affected grain structure and hardness, with beta air cooling transforming grains into Widmanstatten structures and rolling leading to grain refinement and hardness increment through slip and twinning.
METALS AND MATERIALS INTERNATIONAL
(2021)
Article
Chemistry, Physical
Genki Tsukamoto, Tomonori Kunieda, Shigeto Yamasaki, Masatoshi Mitsuhara, Hideharu Nakashima
Summary: The study investigated the effects of grain boundary, grain size, and deformation temperature on twinning deformation in polycrystalline commercially pure titanium. Different twinning systems were observed at different deformation temperatures and grain sizes, indicating the complex interplay between these factors in twinning deformation.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Materials Science, Multidisciplinary
Ji Hoon Kim, Joo-Hee Kang, Chang-Seok Oh
Summary: This study investigates the deformation mechanism and unique mechanical behavior of commercially pure titanium (CP Ti) at room temperature. A micromechanical analysis was conducted using electron backscatter diffraction (EBSD) and crystal plasticity finite element analyses, revealing the statistical data related to the microstructure of titanium sheets. The calibration of crystal plasticity model parameters corresponding to different deformation modes helps to understand the roles of these modes in dictating the anisotropic and asymmetric behavior of CP Ti.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Coatings & Films
Christiane Waechtler, Christina Wuestefeld, Michal Sima, Jan Pikner, David Rafaja
Summary: This article describes the effects of mechanical treatment on the surface morphology of cemented carbide substrates and the microstructure and properties of chemical vapor deposited (CVD) Ti(C,N) coatings. The relationships between substrate surface roughness and the grain size, preferred orientation of crystallites, residual stress, indentation hardness, and coating adhesion are discussed. The results show that surfaces with microscopic steps and edges facilitate the growth of large Ti(C,N) grains with a weak {211} texture, while coatings deposited on smooth substrates have finer grains, a pronounced {211} texture, and better adhesion. The indentation hardness of the coatings is not affected by substrate treatment. The physical background of these relationships is explained.
SURFACE & COATINGS TECHNOLOGY
(2023)
Article
Nanoscience & Nanotechnology
Taylan Ors, Fanny Gouraud, Vincent Michel, Marc Huger, Nathalie Gey, Jean-Sebastien Micha, Olivier Castelnau, Rene Guinebretiere
Summary: Pure zirconia undergoes two solid-state phase transitions from the liquid state to room temperature, with the last transition being martensitic and leading to large volume variations and shear strains. Elastic and inelastic behaviors of zirconia-based materials are strongly influenced by the strain and stress fields induced by this transition. The strains map at the crystal scale in zirconia polycrystals shows huge fluctuations in deviatoric elastic strain, with associated stress levels in the range of 5 GPa and stress gradients of 1 GPa μm(-1).
MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
(2021)
Article
Materials Science, Multidisciplinary
D. J. Shadle, K. E. Nygren, J. C. Stinville, M. A. Charpagne, T. J. H. Long, M. P. Echlin, C. J. Budrowf, A. T. Polonsky, T. M. Pollock, I. J. Beyerlein, M. P. Miller
Summary: Multi-modal approaches are essential for studying complex materials phenomena, as each characterization technique provides a unique perspective. Sometimes, direct interpretations between techniques are not feasible, and indirect interpretations or signatures are needed for a comprehensive understanding. In this study, signature discovery and electron and synchrotron X-ray characterization techniques were combined to identify regions of intense slip localization in an Inconel-718 alloy undergoing mechanical deformation, revealing intergranular stress states within a grain neighborhood.
MATERIALS CHARACTERIZATION
(2023)
Article
Materials Science, Ceramics
Christian Thieme, Katrin Thieme, Richard Busch, Bernhard Fleischmann, Christian Ruessel
Summary: This study compared three types of AZS materials using X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray analysis. The results showed that untreated AZS contained monoclinic ZrO2 and Al2O3, thermally treated AZS showed the presence of mullite, and thermally cycled AZS had an increased concentration of mullite and a small concentration of tetragonal ZrO2. Additionally, tiny monoclinic ZrO2 crystals were embedded within the mullite and Al2O3 crystals.
CERAMICS INTERNATIONAL
(2023)
Article
Energy & Fuels
Mehmet Erman Mert
Summary: The study investigated the efficiency of hydrogen production by doping nickel foam precursors with nickel, cobalt particles, and decorating with silver nano-domes. The catalyst NF/NiCo-2/Ag showed the best performance in terms of lower hydrogen overpotential, higher HPE, stability, and response during the electrolysis process in 1 M KOH.
INTERNATIONAL JOURNAL OF ENERGY RESEARCH
(2022)
Article
Materials Science, Multidisciplinary
Ming-Wei Wu, Jhewn-Kuang Chen, Mo-Kai Tsai, Shih-Hao Wang, Pang-Hsin Lai
Summary: The study identified the influence of heat treatment temperature on the preferred orientation of LPBF Ti-6Al-4V alloy. Results showed that the preferred orientation of α phase gradually intensified with increasing heat treatment temperature, aligning mostly with the building direction after 950 degrees C heat treatment.
Article
Chemistry, Physical
Chang-Hee Cho, Ji-Woon Lee, Kwang-Tae Son, Soong-Keun Hyun
Summary: This study investigated the effects of strain rate on the texture evolution of Al-6Mg alloys during one hour of annealing at 300 degrees C. Grain growth was significant in the 0.1 s(-1) cold-sheared sample, while a texture transition from brass type to copper type was observed in the 1 s(-1) sample. The misorientation indices of all samples decreased with annealing time, indicating a stronger texture anisotropy.
JOURNAL OF ALLOYS AND COMPOUNDS
(2021)
Article
Nanoscience & Nanotechnology
N. B. Zhang, Y. Y. Zhang, S. Chen, B. B. Zhang, Z. L. Li, H. L. Xie, L. Lu, X. H. Yao, S. N. Luo
Summary: This study investigates the onset of detwinning in magnesium alloy Mg-3Al-1Zn under continuous loading using real-time in situ synchrotron X-ray diffraction. The results reveal that detwinning of the {10 (1) over bar2} extension twins occurs immediately upon unloading, regardless of whether the twins are activated by tension parallel to or compression perpendicular to the c-axis fibers.
SCRIPTA MATERIALIA
(2021)
Article
Multidisciplinary Sciences
Sonka Reimers, Dominik Kriegner, Olena Gomonay, Dina Carbone, Filip Krizek, Vit Novak, Richard P. Campion, Francesco Maccherozzi, Alexander Bjorling, Oliver J. Amin, Luke X. Barton, Stuart F. Poole, Khalid A. Omari, Jan Michalicka, Ondrej Man, Jairo Sinova, Tomas Jungwirth, Peter Wadley, Sarnjeet S. Dhesi, Kevin W. Edmonds
Summary: This study reveals that the antiferromagnetic (AF) domain structure in CuMnAs thin films is dominated by nanoscale structural twin defects, which play a crucial role in determining the location and orientation of AF domain walls. The results provide insights into the interplay of crystalline defects, strain, and magnetic ordering in AF materials, offering a route to optimize device performance.
NATURE COMMUNICATIONS
(2022)
Article
Multidisciplinary Sciences
Geoffroy Kremer, Julian Maklar, Laurent Nicolai, Christopher W. Nicholson, Changming Yue, Caio Silva, Philipp Werner, J. Hugo Dil, Juraj Krempasky, Gunther Springholz, Ralph Ernstorfer, Jan Minar, Laurenz Rettig, Claude Monney
Summary: α-GeTe(111) is a non-centrosymmetric ferroelectric semiconductor material with a strong spin-orbit interaction and giant Rashba coupling. Its ferroelectric polarization can be controlled by an electric field at room temperature, and research shows that femtosecond light pulses can modulate the Rashba coupling and enhance the lattice distortion on a femtosecond timescale.
NATURE COMMUNICATIONS
(2022)
Article
Chemistry, Physical
Dalibor Preisler, Michaela Janovska, Hanus Seiner, Lucie Bodnarova, Jitka Nejezchlebova, Martin Koller, Petr Sedlak, Petr Harcuba, Jozef Vesely, Jiri Kozlik, Tomas Chraska, Josef Strasky, Milos Janecek
Summary: Compositionally graded samples of Ti-xNb-7Zr-yO alloys with various chemical compositions were prepared and studied for potential biomedical use. The elastic constants of each sample were determined, showing a dependence on the volume fraction of niobium and oxygen. The lowest elastic modulus was observed near the stability limit between β matrix and α'' martensitic phase, while the presence of isothermal ω particles led to the highest elastic constants.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
Jana Smilauerova, Petr Harcuba, Jitka Straska, Josef Strasky, Milos Janecek, Jiri Pospisil, Jan Ilavsky, Vaclav Holy
Summary: The shapes and orientations of lamellae in single crystals of metastable beta-Ti alloy were investigated using synchrotron small-angle x-ray scattering. The results provide information on the kinetics of the beta-alpha transformation and the thermodynamic equilibrium of the final alpha-beta composite.
MATERIALS CHARACTERIZATION
(2023)
Article
Physics, Multidisciplinary
R. D. Gonzalez Betancourt, J. Zubac, R. Gonzalez-Hernandez, K. Geishendorf, Z. Soban, G. Springholz, K. Olejnik, L. Smejkal, J. Sinova, T. Jungwirth, S. T. B. Goennenwein, A. Thomas, H. Reichlova, J. Zelezny, D. Kriegner
Summary: A spontaneous anomalous Hall signal was observed in an epitaxial film of MnTe, a semiconductor with collinear antiparallel magnetic ordering and zero net magnetization, even in the absence of an external magnetic field. The anomalous Hall effect originates from the unconventional phase with strong time-reversal symmetry breaking and alternating spin polarization. The anisotropic crystal environment of Mn atoms, caused by nonmagnetic Te atoms, plays a vital role in establishing the unconventional phase and generating the anomalous Hall effect.
PHYSICAL REVIEW LETTERS
(2023)
Article
Materials Science, Multidisciplinary
Mayerling Martinez Celis, Petr Harcuba, Jozef Vesely, Florent Moisy, Florent Picot, Richard Retoux, Bernadette Domenges, Eric Hug
Summary: Macrostructure, microstructure, and phase distribution of friction-stir-welded joints between 5083 aluminum alloy and 316L steel were thoroughly analyzed using various analytical techniques. The interface exhibited grain size reduction and the presence of new compounds. Electron diffraction identified the intermetallic compounds at the interface as Al13Fe4 and Al5Fe2 phases. The analysis also revealed the presence of a pseudo-ternary compound with a body-centered cubic structure, Im-3 space group, which is known as alpha-Al(Fe,Mn)Si and is reported for the first time in this type of dissimilar assembly.
JOURNAL OF MATERIALS SCIENCE
(2023)
Article
Physics, Multidisciplinary
Eva Schmoranzerova, Jozef Kimak, Richard Schlitz, Sebastian T. B. Goennenwein, Dominik Kriegner, Helena Reichlova, Zbynek Soban, Gerhard Jakob, Er-Jia Guo, Mathias Klaeui, Markus Muenzenberg, Petr Nemec, Tomas Ostatnicky
Summary: All-optical ferromagnetic resonance (AO-FMR) is used to detect micromagnetic parameters in yttrium iron garnet (YIG) thin films with a metallic capping layer (Au, Pt) by triggering magnetization precession through heating of the metallic layer with femtosecond laser pulses. The laser-induced precession corresponds to a uniform (Kittel) magnon mode, allowing for the measurement of local magnetic properties with a resolution determined by the laser spot size.
NEW JOURNAL OF PHYSICS
(2023)
Article
Materials Science, Multidisciplinary
A. Veverkova, P. Harcuba, J. Vesely, P. Barriobero-Vila, P. Dolezal, J. Pospisil, K. Bartha, J. Smilauerova, J. Kozlik, J. Strasky, M. Janecek
Summary: Phase transformations in a metastable beta Zr-12Nb alloy were investigated using high-energy X-ray diffraction (HEXRD) and complementary in-situ methods. Two bcc phases, l3Zr and l3Nb, were observed in the temperature range studied. The formation of l3Nb phase starts at about 300 degrees C, gradually replacing the original l3Zr phase. Ex-situ observations revealed a cuboidal shape of the u particles and the dissolution of u particles followed by the growth of the a phase at 560 degrees C.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Materials Science, Multidisciplinary
Ismaila Kounta, Helena Reichlova, Dominik Kriegner, Rafael Lopes Seeger, Antonin Bad'ura, Miina Leiviska, Amine Boussadi, Vasile Heresanu, Sylvain Bertaina, Matthieu Petit, Eva Schmoranzerova, Libor Smejkal, Jairo Sinova, Tomas Jungwirth, Vincent Baltz, Sebastian T. B. Goennenwein, Lisa Michez
Summary: Some magnetically ordered phases of the Mn5Si3 crystal are being studied as prototypes for new fundamental spin physics related to the breaking of time-reversal symmetry. Epitaxial Mn5Si3 thin films were grown on Si(111) using Mn and Si codeposition in a molecular beam epitaxy system with carefully controlled deposition rates, growth temperature, and annealing temperature. The formation and morphology of the silicide phase were assessed using various techniques. High-quality crystalline Mn5Si3 thin films were successfully formed under restrictive conditions, and the magnetic and magnetotransport properties were used to track the crystallinity and proportion of Mn5Si3 in the deposited layers.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Materials Science, Multidisciplinary
Changqing Zhu, Patrick Pilch, Anneke Reinold, Dennis Kudlacik, Gunther Springholz, Alberta Bonanni, Marc Assmann, Mirko Cinchetti, Zhe Wang
Summary: We present a study on the time-resolved optical and terahertz ultrafast spectroscopy of charge-carrier dynamics in the room-temperature antiferromagnetic semiconductor alpha-MnTe. By optically pumping the system with 1.55 eV photons at room temperature, charge carriers are excited in the conduction band and their dynamical response in the nonequilibrium states is investigated using optical and terahertz transmission probes. Three relaxation processes with characteristic relaxation times of approximately 1, 10, and 100 ps are identified, and their exact values depend on the pump fluence. Nonlinear dependence on the pump fluence is observed in both the optical and terahertz probes at high pump fluences.
PHYSICAL REVIEW MATERIALS
(2023)
Article
Chemistry, Physical
Kristian Mathis, Andrea Farkas, Michal Knapek, Andriy Ostapovets, Gergely Farkas, Gergely Nemeth, Petr Harcuba, Daria Drozdenko
Summary: Ultra-high-speed camera (UHSC) imaging was used to study how the gadolinium (Gd) content affects the longitudinal growth of twins in Mg-Gd binary alloys. The results showed that the twin propagation rate is approximately 101 m/s and decreases with increasing Gd concentration. Concurrent molecular dynamics (MD) simulations revealed that the presence of Gd atoms promotes the formation of stacking faults (SFs), which hinder twin propagation as effectively as twin boundary pinning by Gd solutes. Consequently, the twin tip exhibits intermittent motion at the microscopic level.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Chemistry, Analytical
Mariapompea Cutroneo, Letteria Silipigni, Anna Mackova, Petr Malinsky, Romana Miksova, Vaclav Holy, Jan Maly, Marcel Stofik, Petr Aubrecht, Dominik Fajstavr, Petr Slepicka, Lorenzo Torrisi
Summary: Cyclic olefin copolymer (COC) is a thermoplastic polymer with potential applications in electronic, optoelectronic, biomedicine and packaging industries. However, its hydrophobicity limits its practical uses. In this study, Ti was deposited on selected areas of COC films using pulsed lased deposition. The Ti/COC film showed a 20% decrease in transmittance and reduced hydrophilicity compared to the pristine polymer. The morphology of the deposited Ti was assessed using scanning electron microscopy (SEM) and atomic force microscopy (AFM).
Article
Materials Science, Multidisciplinary
J. Bermejo-Ortiz, G. Krizman, R. Jakiela, Z. Khosravizadeh, M. Hajlaoui, G. Bauer, G. Springholz, L. -A. de Vaulchier, Y. Guldner
Summary: On smooth interfaces between a trivial and a topological material, massless Weyl and massive Dirac fermions coexist, with their energy spectra controlled by the smoothness of the topological interface. The optical absorption of the zero-energy chiral Weyl state is also affected by the smoothness of the interface.
Article
Materials Science, Multidisciplinary
E. Schmoranzerova, T. Ostatnicky, J. Kimak, D. Kriegner, H. Reichlova, R. Schlitz, A. Badura, Z. Soban, M. Muenzenberg, G. Jakob, E-J Guo, M. Klaeui, P. Nemec
Summary: We observed a giant quadratic magneto-optical effect in a 50 nm thick YIG layer. Through theoretical and experimental methods, we quantified both linear and quadratic magneto-optical effects in the studied material. The quadratic magneto-optical signal in the thin YIG film exceeded the linear response, reaching values of 450 grads that are comparable with Heusler alloys or ferromagnetic semiconductors. This enhancement is attributed to antiferromagnetic coupling of two Fe sublattices. We also found that the choice of experimental conditions, particularly the wavelength, is crucial for optimizing the quadratic magneto-optical effect.
