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Crystals, Volume 14, Issue 3 (March 2024) – 91 articles

Cover Story (view full-size image): Lithium-ion batteries are a widely used technology prized for their high energy density. However, to further improve their energy density and performance, new anode materials are sought. Transitional metal oxides offer high capacities but often suffer from poor cycling stability. High-entropy oxides (HEOs) are attracting interest as anode materials due to their potential for high capacity and improved cycling stability. This study investigates (CrMnFeCoCu)3O4, an HEO with a spinel structure, synthesized for the first time using an alloy oxidation method, and evaluated for its performance as a Li-ion battery anode. Its electrochemical performance was characterized in half-cells including long-term cycling up to 1000 cycles. The material showed moderate cyclic stability at medium current density. View this paper
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20 pages, 3398 KiB  
Article
Photocatalytic Decomposition of Amoxicillin Using Zinc Ferrite Nanoparticles
by Aya Jezzini, Yujin Chen, Anne Davidson, Gilles Wallez, Tayssir Hamieh and Joumana Toufaily
Crystals 2024, 14(3), 291; https://doi.org/10.3390/cryst14030291 - 21 Mar 2024
Viewed by 732
Abstract
Catalysts enriched in Zinc ferrite (ZFO) were synthesized using coprecipitation and hydrothermal methods. Mixtures of crystalline nanoparticles (ZFO and α-Fe2O3, several allotropic varieties of FeO) were characterized by various techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM, [...] Read more.
Catalysts enriched in Zinc ferrite (ZFO) were synthesized using coprecipitation and hydrothermal methods. Mixtures of crystalline nanoparticles (ZFO and α-Fe2O3, several allotropic varieties of FeO) were characterized by various techniques such as X-ray diffraction (XRD), transmission electron microscopy (TEM, SEM), N2 sorption, UV-visible spectrophotometry (UV-Vis) and X-ray photoelectron spectroscopy (XPS). After detailed characterizations, the catalytic performance of the solids (1 g/L) in the degradation of amoxicillin (AMX) (10 mg/L) as an antibiotic pollutant in water was evaluated. In addition, we used air as the oxygen source and adjusted the pH to 5.0. Consequently, the catalysts obtained via the hydrothermal method HT-ZFO had a high activity (100% of AMX removal in less than 100 min when an LED (75 W) light was used) compared to a similar mixture of oxides with graphene HT-ZFO-GO (a longer time of 150 min) that was necessary for the complete degradation of AMX. Impregnation with an aqueous solution containing 80 mg of GO obtained using Hummer’s method, reduced into RGO by an ultrasound treatment, enhances the initial reaction rate but is associated with a prolonged time for complete AMX removal (10 ppm in water) that we attribute to its spontaneous corrosion. Full article
(This article belongs to the Special Issue Photocatalytic Materials: New Perspectives and Challenges)
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15 pages, 14364 KiB  
Article
Microstructural Analysis on Grain Boundary of Boron– and Zirconium–Containing Wrought Nickel-Based Superalloys
by Byungil Kang, Youngki Lee, Jongmin Kim, Taekyu Ha and Youngjig Kim
Crystals 2024, 14(3), 290; https://doi.org/10.3390/cryst14030290 - 21 Mar 2024
Viewed by 612
Abstract
Trace elements such as boron (B) and zirconium (Zr) can increase creep resistance in nickel-based superalloys. This study investigates the change of microstructures on the grain boundary (GB) in phase-controlled nickel-based superalloys through the addition of trace elements. The basis alloy without B [...] Read more.
Trace elements such as boron (B) and zirconium (Zr) can increase creep resistance in nickel-based superalloys. This study investigates the change of microstructures on the grain boundary (GB) in phase-controlled nickel-based superalloys through the addition of trace elements. The basis alloy without B and Zr has distributed micrometer-sized (Nb, Ti)C and Cr23C6 carbides at the GBs. Zr is detected alongside Nb and Ti within certain (Nb, Ti)C carbides and its addition increases the fraction of (Nb, Ti)C or (Nb, Ti, Zr)C carbides. B affects the formation of precipitates constructed by nanometer-sized precipitates, which are Cr23C6 carbides, Cr23(C, B)6 boro-carbides, and Cr-rich borides, surrounded by γ’ phases. This film structure, which includes nanometer-sized precipitates surrounded by γ’ phases, forms more continuously with the addition of B and Zr. It is constructed with precipitates of (Nb, Ti)C carbides and Cr23(C, B)6 boro-carbides surrounded by γ’ phases. Numerous nanometer-sized precipitates (i.e., (Nb, Ti)C and Cr23(C, B)6) are distributed alternately within the film structure. The effect of the addition of B and Zr is such that nucleation sites of each precipitate are formed simultaneously and alternately along the GBs. The experimental results were discussed by correlating them with the predicted fraction of stable phases depending on the temperatures of these alloys, using the JMatPro program. Full article
(This article belongs to the Section Crystalline Metals and Alloys)
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11 pages, 8891 KiB  
Article
Improving the Quality of Spontaneously Growing HviGH11 Crystals by Increasing the Viscosity Using Polyethylene Glycols
by Ki Hyun Nam
Crystals 2024, 14(3), 289; https://doi.org/10.3390/cryst14030289 - 21 Mar 2024
Viewed by 631
Abstract
Proteins can form crystals spontaneously without crystallization experiments. These crystals can be used to determine three-dimensional structures. However, when X-ray diffraction is poor, crystal optimization is required to obtain a high-resolution crystal structure. Endo-1,4-β-xylanase from the fungus Hypocrea virens (HviGH11) spontaneously formed microcrystals [...] Read more.
Proteins can form crystals spontaneously without crystallization experiments. These crystals can be used to determine three-dimensional structures. However, when X-ray diffraction is poor, crystal optimization is required to obtain a high-resolution crystal structure. Endo-1,4-β-xylanase from the fungus Hypocrea virens (HviGH11) spontaneously formed microcrystals after affinity purification and concentration; however, most HviGH11 microcrystals showed poor diffraction in the synchrotron X-ray and X-ray free-electron laser, so a complete three-dimensional structure could not be obtained. This study presents a method to improve the crystal quality of spontaneously grown HviGH11 microcrystals. The crystallization screening results revealed that temperature, pH, and salt were not crucial factors in increasing the solubility or preventing the spontaneous crystal growth of HviGH11. Conversely, the addition of polyethylene glycols (PEGs) as a precipitant facilitated the growth of larger HviGH11 crystals. The improved large HviGH11 crystal showed a diffraction of up to 1.95 Å when exposed to synchrotron X-rays, providing a complete three-dimensional structural dataset. Based on the nucleation rate equation, it was suggested that PEG increases the viscosity of the protein solution rather than promoting nucleation. This increase in viscosity reduced nucleation and facilitated the growth of larger HviGH11 crystals. These results provide valuable insights for future experiments aimed at increasing the size of spontaneously grown crystals. Full article
(This article belongs to the Section Biomolecular Crystals)
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7 pages, 1423 KiB  
Communication
Single Crystal Growth and X-ray Diffraction Characterization of a Quasi-Spin Chain Compound, Li2CuO2
by Ashiwini Balodhi and Min Gyu Kim
Crystals 2024, 14(3), 288; https://doi.org/10.3390/cryst14030288 - 21 Mar 2024
Viewed by 637
Abstract
We report the growth of single crystals and X-ray diffraction characterization of the quasi-one-dimensional spin chain compound, Li2CuO2. The single crystals were grown using the high-temperature solution growth technique. The resulting blade-shaped crystals exhibit a shiny black color, with [...] Read more.
We report the growth of single crystals and X-ray diffraction characterization of the quasi-one-dimensional spin chain compound, Li2CuO2. The single crystals were grown using the high-temperature solution growth technique. The resulting blade-shaped crystals exhibit a shiny black color, with dimensions reaching several millimeters along the crystallographic b-axis. The as-grown crystals were characterized using powder X-ray diffraction and Laue back reflection. The I-centered orthorhombic, Immm, structure was confirmed. Crystal structure parameters were determined to be a = 3.6744 Å, b = 2.8600 Å, and c = 9.4257 Å from Rietveld analysis. Our work helps to remove obstacles to the synthesis and study of a model cuprate system, Li2CuO2, facilitating the use of experimental probes that require sizable crystals. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
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10 pages, 1429 KiB  
Article
Revisiting the Crystallography of {225}γ Martensite: How EBSD Can Help to Solve Long-Standing Controversy
by Loïc Malet and Stéphane Godet
Crystals 2024, 14(3), 287; https://doi.org/10.3390/cryst14030287 - 20 Mar 2024
Viewed by 569
Abstract
Explaining the crystallography of iron alloys martensite with a {225}γ habit plane remains a challenging task within the phenomenological theory of martensite crystallography. The purpose of this study is to re-examine the martensite formed in a Fe-8Cr-1.1C alloy using EBSD, which has [...] Read more.
Explaining the crystallography of iron alloys martensite with a {225}γ habit plane remains a challenging task within the phenomenological theory of martensite crystallography. The purpose of this study is to re-examine the martensite formed in a Fe-8Cr-1.1C alloy using EBSD, which has a better angular resolution than the conventional transmission electron diffraction techniques previously used. The results show that the single morphological plates, which hold a near {225}γ habit plane, are bivariant composites made up of two twin-related variants. It is shown that a {113}γ plane is systematically parallel to one of the three common 112α planes between the two twin-related crystals. This observation suggests that the lattice invariant strain of transformation occurs through a dislocation glide on the {113}γ ⟨110⟩γ system, rather than through twinning as is commonly accepted. Based on this assumption, the predictions of Bowles and Mackenzie’s original theory are in good agreement with the crystallographic features of {225}γ martensite. Unexpectedly, it is the high shear solution of the theory that gives the most accurate experimental predictions. Full article
(This article belongs to the Section Crystalline Metals and Alloys)
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15 pages, 3738 KiB  
Article
Estimation of Ionic Impurities in Poly(propylene Glycol) Diacrylate Monomers/Liquid Crystal E7 Mixtures Using Dielectric Spectroscopy
by Tayeb Benkouider, Yazid Derouiche, Lahcene Souli, Frédéric Dubois, Ana Barrera, Zohra Bouberka and Ulrich Maschke
Crystals 2024, 14(3), 286; https://doi.org/10.3390/cryst14030286 - 20 Mar 2024
Viewed by 678
Abstract
The study investigated the effect of the molecular weight of three difunctional poly(propylene glycol) diacrylates on the temperature-dependent ionic conductivity of these monomers and their blends with an eutectic nematic liquid crystal mixture (E7). The results revealed two distinct regions. At low temperatures, [...] Read more.
The study investigated the effect of the molecular weight of three difunctional poly(propylene glycol) diacrylates on the temperature-dependent ionic conductivity of these monomers and their blends with an eutectic nematic liquid crystal mixture (E7). The results revealed two distinct regions. At low temperatures, ionic conduction can be described by the Vogel–Tamman–Fulcher (VTF) equation, while at high temperatures, the conductivity data follow the prediction of the Arrhenius model. The Arrhenius and VTF parameters and their corresponding activation energies were determined using the least squares method. In addition, a conductivity analysis based on an ionic hopping model is proposed. Estimates of ion concentrations and diffusion constants were calculated. It was found that both the ionic concentration and the diffusion constant decrease with the increase in the molecular weight of the monomers. The static dielectric permittivity decreases in the following order: TPGDA, PPGDA540, and PPGDA900. This can be explained by the higher dipole moment of TPGDA, which is caused by an enhanced volume density of carbonyl groups. Full article
(This article belongs to the Topic Recent Advances in Liquid Crystals)
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14 pages, 15658 KiB  
Article
Reduction of Process Induced Porosity for Ultrafuse 316L through Parameter Optimization of Creality Ender 3 V2 and Makerbot Method X
by Jeffery Logan Betts, Bradley J. Sampson, Kyle Lindsey, Frank M. Brinkley and Matthew W. Priddy
Crystals 2024, 14(3), 285; https://doi.org/10.3390/cryst14030285 - 20 Mar 2024
Viewed by 711
Abstract
Metal-based additive manufacturing (MBAM) has enabled rapid prototyping and one-off production, but the cost of equipment has limited widespread adoption. Recent developments in hybrid filaments and processes have created more accessible methods for MBAM, leveraging common fused filament fabrication (FFF) printers and Ultrafuse [...] Read more.
Metal-based additive manufacturing (MBAM) has enabled rapid prototyping and one-off production, but the cost of equipment has limited widespread adoption. Recent developments in hybrid filaments and processes have created more accessible methods for MBAM, leveraging common fused filament fabrication (FFF) printers and Ultrafuse 316L metal filament. This technique has shown promise but suffered from large pore formations along parallel print paths. To reduce the formation of process-dependent pores, a design of experiments (DOE) was conducted to investigate the effects of varying extrusion parameters such as layer height, line width, and extrusion multiplier for tensile samples produced on a Creality Ender 3 V2 and MakerBot Method X. Characterization techniques included tensile testing, microhardness, density measurements, and optical microscopy; findings were compared to samples produced via laser-powder bed fusion (L-PBF) and from 316L plate. The Method X produced components with approximately 1% porosity and the Ender 4% porosity. Mechanical properties for both FFF printers were comparable to previous research, with an increase in tensile strength for the Method X. Despite the increased porosity in the Ender samples, only a 7% reduction in strength from the average yield in Method X samples (153.6 MPa) was observed. It was found that a combination of increased layer height and extrusion rate led to improved mechanical properties in parts printed on the Ender, while the default Makerbot settings resulted in the best overall performance for Ultrafuse 316L samples. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
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15 pages, 4872 KiB  
Article
High-Performance Catalytic Reduction of 4-Nitrophenol to 4-Aminophenol over Pt Nanoparticles Supported on Co-Al LDH Nanosheets
by Chenzhe Xu, Yue Qiu, Xiaoting Yang, Zifei Gao, Zheng Wang, Cai Liu, Yanran Sun, Juanjuan Ma and Lin Liu
Crystals 2024, 14(3), 284; https://doi.org/10.3390/cryst14030284 - 19 Mar 2024
Viewed by 872
Abstract
In this study, a Pt@Co-Al LDH hybrid structure was fabricated by assembling the metal precursor PtCl62− with the exfoliated LDH nanosheets followed by in situ reduction by NaBH4. The morphology, composition and microstructure of the hybrid were characterized by [...] Read more.
In this study, a Pt@Co-Al LDH hybrid structure was fabricated by assembling the metal precursor PtCl62− with the exfoliated LDH nanosheets followed by in situ reduction by NaBH4. The morphology, composition and microstructure of the hybrid were characterized by FESEM, HRTEM, XRD, XPS and BET techniques. Pt nanoparticles (NPs) with an average particle size of 3.1 nm were successfully and uniformly loaded on the surface of LDH nanosheets. The catalytic activity of the Pt@Co-Al LDH hybrid was tested for the reduction of 4-nitrophenol, which is one of the most frequent pollutants in wastewater effluent from the pharmaceutical and textile industries. The hybrid displays superior catalytic activity and stability in the reduction of 4-NP under environmental conditions with NaBH4 as a reducing agent. The hybrid can be recovered in a simple way and still shows high catalytic activity after five reuses. Full article
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12 pages, 7883 KiB  
Article
Crystallography and Interface Structures in As-Arc Melted and Laser Surface-Remelted Aluminum–Silicon Alloys with and without Strontium Addition
by Bibhu P. Sahu, Mohsen T. Andani, Arkajit Ghosh, Jian Wang and Amit Misra
Crystals 2024, 14(3), 283; https://doi.org/10.3390/cryst14030283 - 18 Mar 2024
Viewed by 669
Abstract
The crystallography of the eutectic Al-Si microstructure in both unmodified and Sr (0.2 wt.%)-modified hypereutectic Al-20 wt.% Si alloys, processed via arc-melting and laser surface remelting, has been comprehensively characterized using transmission electron microscopy and electron diffraction. Although, under as-cast conditions, specific orientations [...] Read more.
The crystallography of the eutectic Al-Si microstructure in both unmodified and Sr (0.2 wt.%)-modified hypereutectic Al-20 wt.% Si alloys, processed via arc-melting and laser surface remelting, has been comprehensively characterized using transmission electron microscopy and electron diffraction. Although, under as-cast conditions, specific orientations between different planes of Al and Si, satisfying defined orientation relationships (ORs), have been investigated within the flake morphology, the rapid solidification induced by laser surface remelting results in a notable transformation from a flake morphology to nanocrystalline Si fibers dispersed in an Al matrix. Consequently, this transformation results in a mis-orientation of the interface between the eutectic Al and Si phases, preventing the formation of orientation relationships, thus promoting the formation of faceted interfaces exhibiting substantial lattice disregistry. Full article
(This article belongs to the Section Crystalline Metals and Alloys)
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2 pages, 147 KiB  
Correction
Correction: Pang et al. Burning Rate Prediction of Solid Rocket Propellant (SRP) with High-Energy Materials Genome (HEMG). Crystals 2023, 13, 237
by Weiqiang Pang, Victor Abrukov, Darya Anufrieva and Dongping Chen
Crystals 2024, 14(3), 282; https://doi.org/10.3390/cryst14030282 - 18 Mar 2024
Viewed by 527
Abstract
There was an error in the original publication [...] Full article
(This article belongs to the Special Issue Advanced Energetic Materials: Testing and Modeling)
18 pages, 5138 KiB  
Article
Synthesis and Crystallographic Characterization of Heteroleptic Ir(III) Complexes Containing the N-oxide Functional Group and Crystallographic Characterization of Ir(III) N-oxide Precursors
by Emily E. Stumbo, Emarald K. Hodge, Matthew Williams, Diana A. Thornton, Colin D. McMillen and Jared A. Pienkos
Crystals 2024, 14(3), 281; https://doi.org/10.3390/cryst14030281 - 16 Mar 2024
Viewed by 1599
Abstract
The N-oxide functional group has been exploited for synthetic strategies and drug design, and it has been utilized in imaging agents. Herein, we present rare examples of neutral heteroleptic cyclometallated Ir(III) compounds that contain an uncoordinated N-oxide functional group. These species, [...] Read more.
The N-oxide functional group has been exploited for synthetic strategies and drug design, and it has been utilized in imaging agents. Herein, we present rare examples of neutral heteroleptic cyclometallated Ir(III) compounds that contain an uncoordinated N-oxide functional group. These species, along with others described within, were verified by NMR, EA, HRMS, and single-crystal X-ray analysis. N-oxide-containing Ir(III) species were prepared selectively in high yields > 66% from chloro-bridged Ir(III) dimers with Acipimox, a picolinate-type ligand containing the N-oxide functional group. Non-N-oxide analogs were synthesized in a similar fashion (yields > 77%). Electrochemical comparison (cyclic voltammetry) indicates that the presence of an N-oxide functional group anodically shifts the reduction potential, suggesting that the N-oxide is acting as an electron-withdrawing group in these species. Crystallographic studies were pursued to examine the coordination behavior of these N-oxides compared to their non-oxidized congeners. The Ir(III) complexes with Acipimox indeed leave the N-oxide uncoordinated and exposed on the complexes. The uncoordinated N-oxide group is influential in directing the packing structures of these complexes directly through C-H···O and O···π interactions at the N-oxide. The crystallographic characterization of cationic Ir(III) compounds with uncoordinated nitrogen atoms is also presented. The C-H···N interactions between these complexes form a variety of dimers, finite chains, and continuous chains. Future work will focus on functionalizing the cationic Ir(III) species into their corresponding N-oxide derivatives and rigorously characterizing how the N-oxide functional group impacts the optical properties of transition metal compounds in both cationic and neutral complexes. Full article
(This article belongs to the Section Macromolecular Crystals)
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7 pages, 1856 KiB  
Communication
Machinability of MoS2 after Oxygen Plasma Treatment under Mechanical Scanning Probe Lithography
by Yang He, Xing Su and Kuo Hai
Crystals 2024, 14(3), 280; https://doi.org/10.3390/cryst14030280 - 15 Mar 2024
Viewed by 639
Abstract
The surface of molybdenum disulfide (MoS2) underwent oxygen plasma treatment to enhance its machinability and mitigate the tearing effects commonly associated with mechanical forces on 2D materials. This treatment led to the oxidation of the atoms on the top 1–3 layers [...] Read more.
The surface of molybdenum disulfide (MoS2) underwent oxygen plasma treatment to enhance its machinability and mitigate the tearing effects commonly associated with mechanical forces on 2D materials. This treatment led to the oxidation of the atoms on the top 1–3 layers of MoS2, resulting in the formation of MoO3 on the surface. During mechanical scanning probe lithography (m-SPL), only the surface oxide layer was uniformly removed, with material accumulation occurring predominantly on one side of the machined area. The resolution of the machining process was significantly enhanced via dynamic lithography while maintaining atomic-level smoothness in the machined area. Importantly, these techniques only removed the surface oxide layer, preserving the integrity of the underlying MoS2 surface, which was pivotal in avoiding damage to the original material structure. This study provided valuable insights and practical guidance for the nanofabrication of transition metal dichalcogenides (TMDCs) nanodevices, demonstrating a method to finely tune the machining of these materials. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
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13 pages, 5885 KiB  
Article
Structural Evolution and Mechanical Behavior of Ytterbia Doped Hafnia Biphasic Ceramics under Annealing at 1500 °C
by Yang Wu, Hao Lan, Xiaoming Sun, Zihao Hu, Yonghui Sun, Huifeng Zhang, Chuanbing Huang and Weigang Zhang
Crystals 2024, 14(3), 279; https://doi.org/10.3390/cryst14030279 - 15 Mar 2024
Viewed by 609
Abstract
HfO2 has become a promising thermal barrier coating material due to its similarity in structure and chemical properties with ZrO2 and its higher phase structure transition temperature. However, the fracture toughness of HfO2 is not ideal, greatly limiting its application. [...] Read more.
HfO2 has become a promising thermal barrier coating material due to its similarity in structure and chemical properties with ZrO2 and its higher phase structure transition temperature. However, the fracture toughness of HfO2 is not ideal, greatly limiting its application. In this report, we find a special sandwich structure of ceramics, comprising a cubic (C) phase /monoclinic (M) phase/cubic (C) phase. The microstructural evolution and mechanical properties of these ceramics were investigated under annealing at 1500 °C. The results indicate that, with an increase in annealing duration, there was a gradual augmentation in the proportion of the monoclinic (M) phase and the fracture toughness increased from 2.18 MPa·m0.5 to 2.83 MPa·m0.5 after 48 h of annealing, which is higher than many potential TBC materials. The residual compressive stress present in the M phases during the progression of crack propagation served to facilitate the bridging and deflection of cracks. As such, this process led to the alleviation of stress concentration at the crack tip, ultimately enhancing the toughening effect. Full article
(This article belongs to the Special Issue Ceramics: Processes, Microstructures, and Properties)
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14 pages, 2234 KiB  
Article
CaH2-Assisted Molten Salt Synthesis of Zinc-Rich Intermetallic Compounds of RhZn13 and Pt3Zn10 for Catalytic Selective Hydrogenation Application
by Yasukazu Kobayashi, Koharu Yamamoto and Ryo Shoji
Crystals 2024, 14(3), 278; https://doi.org/10.3390/cryst14030278 - 15 Mar 2024
Viewed by 742
Abstract
Zinc-included intermetallic compound catalysts of RhZn, PtZn, and PdZn with a molar ration of Zn/metal = 1/1, which are generally prepared using a hydrogen reduction approach, are known to show excellent catalytic performance in some selective hydrogenations of organic compounds. In this study, [...] Read more.
Zinc-included intermetallic compound catalysts of RhZn, PtZn, and PdZn with a molar ration of Zn/metal = 1/1, which are generally prepared using a hydrogen reduction approach, are known to show excellent catalytic performance in some selective hydrogenations of organic compounds. In this study, in order to reduce the incorporated mounts of the expensive noble metals, we attempted to prepare zinc-rich intermetallic compounds via a CaH2-assisted molten salt synthesis method with a stronger reduction capacity than the common hydrogen reduction method. X-ray diffraction results indicated the formation of RhZn13 and Pt3Zn10 in the samples prepared by the reduction of ZnO-supported metal precursors. In a hydrogenation reaction of p-nitrophenol to p-aminophenol, the ZnO-supported RhZn13 and Pt3Zn10 catalysts showed a higher selectivity than the RhZn/ZnO and PtZn/ZnO catalysts with the almost similar conversions. Thus, it was demonstrated that the zinc-rich intermetallic compounds of RhZn13 and Pt3Zn10 could be superior selective hydrogenation catalysts compared to the conventional intermetallic compound catalysts of RhZn and PtZn. Full article
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1 pages, 163 KiB  
Correction
Correction: Lopresti, M. et al. The Crystal Structure of Calcium Sebacate by X-ray Powder Diffraction Data. Crystals 2023, 13, 261
by Mattia Lopresti, Marco Milanesio and Luca Palin
Crystals 2024, 14(3), 277; https://doi.org/10.3390/cryst14030277 - 15 Mar 2024
Viewed by 487
Abstract
In the original publication [...] Full article
(This article belongs to the Special Issue Young Crystallographers Across Europe)
12 pages, 3561 KiB  
Article
Comparative Analysis of Room Temperature Structures Determined by Macromolecular and Serial Crystallography
by Ki Hyun Nam
Crystals 2024, 14(3), 276; https://doi.org/10.3390/cryst14030276 - 14 Mar 2024
Viewed by 772
Abstract
Temperature directly influences the function and structure of proteins. Crystal structures determined at room temperature offer more biologically relevant structural information regarding flexibility, rigidity, and thermal motion than those determined by conventional cryocrystallography. Crystal structures can be determined at room temperature using conventional [...] Read more.
Temperature directly influences the function and structure of proteins. Crystal structures determined at room temperature offer more biologically relevant structural information regarding flexibility, rigidity, and thermal motion than those determined by conventional cryocrystallography. Crystal structures can be determined at room temperature using conventional macromolecular crystallography (MX) or serial crystallography (SX) techniques. Among these, MX may theoretically be affected by radiation damage or X-ray heating, potentially resulting in differences between the room temperature structures determined by MX and SX, but this has not been fully elucidated. In this study, the room temperature structure of xylanase GH11 from Thermoanaerobacterium saccharolyticum was determined by MX (RT-TsaGH11-MX). The RT-TsaGH11-MX exhibited both the open and closed conformations of the substrate-binding cleft within the β-sandwich fold. The RT-TsaGH11-MX showed distinct structural changes and molecular flexibility when compared with the RT-TsaGH11 determined via serial synchrotron crystallography. The notable molecular conformation and flexibility of the RT-TsaGH11-MX may be induced by radiation damage and X-ray heating. These findings will broaden our understanding of the potential limitations of room temperature structures determined by MX. Full article
(This article belongs to the Section Macromolecular Crystals)
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13 pages, 3398 KiB  
Review
Decoding Material Structures with Scanning Electron Diffraction Techniques
by Sangmoon Yoon
Crystals 2024, 14(3), 275; https://doi.org/10.3390/cryst14030275 - 14 Mar 2024
Viewed by 743
Abstract
Recent advancements in electron detectors and computing power have revolutionized the rapid recording of millions of 2D diffraction patterns across a grid of probe positions, known as four-dimensional scanning transmission electron microscopy (4D-STEM). These datasets serve as the foundation for innovative STEM imaging [...] Read more.
Recent advancements in electron detectors and computing power have revolutionized the rapid recording of millions of 2D diffraction patterns across a grid of probe positions, known as four-dimensional scanning transmission electron microscopy (4D-STEM). These datasets serve as the foundation for innovative STEM imaging techniques like integrated center of mass (iCOM) and symmetry STEM (S-STEM). This paper delves into the application of 4D-STEM datasets for diffraction analysis. We therefore use the term scanning electron diffraction (SED) instead of 4D-STEM in this review. We comprehensively explore groundbreaking diffraction methods based on SED, structured into two main segments: (i) utilizing an atomic-scale electron probe and (ii) employing a nanoscale electron probe. Achieving an atomic-scale electron probe necessitates a significant convergence angle (α > 30 mrad), leading to interference between direct and diffracted beams, distinguishing it from its nanoscale counterpart. Additionally, integrating machine learning approaches with SED experiments holds promise in various directions, as discussed in this review. Our aim is to equip materials scientists with valuable insights for characterizing atomic structures using cutting-edge SED techniques. Full article
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13 pages, 60340 KiB  
Article
The Effect of Annealing Treatment on the Microstructure and Texture of a Cold-Rolled TiNiFe Shape Memory Alloy Tube
by Jianxian Wen, Xiaoyun Song, Yanfeng Li, Shuwei Liu, Yang Yu, Wenjun Ye and Songxiao Hui
Crystals 2024, 14(3), 274; https://doi.org/10.3390/cryst14030274 - 14 Mar 2024
Viewed by 623
Abstract
The effect of annealing treatment on the microstructure and texture of a Ti50Ni47Fe3 shape memory alloy tube was studied. The results show that the recrystallization process of a cold-rolled Ti50Ni47Fe3 alloy tube occurs [...] Read more.
The effect of annealing treatment on the microstructure and texture of a Ti50Ni47Fe3 shape memory alloy tube was studied. The results show that the recrystallization process of a cold-rolled Ti50Ni47Fe3 alloy tube occurs at 600 °C. The microstructure changes from long striped grains to equiaxed recrystallized grains. The main texture of the alloy tube is the fiber texture <111> parallel to RD. With the increase in the annealing temperature, the crystal orientation of the alloy gradually turned to (111)<112>, and a series of secondary textures were distributed along the γ orientation line when the alloy was annealed at a lower temperature (450~600 °C). When the alloy was annealed at 650 °C, the growth of recrystallized grains made the grain orientation change, which led to the weakening of the γ-fiber texture and the formation of recrystallization textures. Full article
(This article belongs to the Section Crystalline Metals and Alloys)
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19 pages, 2852 KiB  
Review
Multi-Source Ferrous Metallurgical Dust and Sludge Recycling: Present Situation and Future Prospects
by Jiansong Zhang, Yuzhu Zhang, Yue Long, Peipei Du, Tielei Tian and Qianqian Ren
Crystals 2024, 14(3), 273; https://doi.org/10.3390/cryst14030273 - 13 Mar 2024
Viewed by 938
Abstract
Multi-source ferrous metallurgical dust and sludge are significant components of iron-containing solid waste in the iron and steel industry. It is crucial for the sustainable operation of steel enterprises to recycle iron from ferrous metallurgical dust and sludge (FMDS) for use in steel [...] Read more.
Multi-source ferrous metallurgical dust and sludge are significant components of iron-containing solid waste in the iron and steel industry. It is crucial for the sustainable operation of steel enterprises to recycle iron from ferrous metallurgical dust and sludge (FMDS) for use in steel smelting. However, besides Fe, FMDS also contains valuable elements such as Zn, Pb, K, and Na, among others. While these valuable elements hold high recovery value, they impede the direct reuse of FMDS by iron and steel enterprises. This paper introduces the compositional characteristics of multi-source ferrous metallurgical dust and sludge, analyzes the main recycling technologies associated with FMDS at the present stage of development, and discusses the characteristics of different technologies. In view of this, a new idea of the “cooperative treatment of multi-source ferrous metallurgical dust and sludge—full quantitative recovery of valuable elements” is put forward. This new idea integrates a variety of treatment processes to directly recycle FMDS within the steel plant, enhancing the adequacy of dust and sludge recovery and reducing the risk of environmental pollution. This paper provides a reference for achieving the full quantification and utilization of high-value-added FMDS in steel plants. Full article
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14 pages, 11558 KiB  
Article
Molecular Dynamics Study of Friction between Ag Nanoparticle and Two-Dimensional Titanium Carbide Ti2C (MXene)
by Vadym Borysiuk, Iakov A. Lyashenko and Valentin L. Popov
Crystals 2024, 14(3), 272; https://doi.org/10.3390/cryst14030272 - 12 Mar 2024
Viewed by 809
Abstract
We report the results of atomistic simulations of friction between two-dimensional titanium carbide Ti2C (MXene) and a silver nanoparticle located on its surface. Numerical experiments were performed within classical molecular dynamics methods using a previously developed scheme for simulations of interactions [...] Read more.
We report the results of atomistic simulations of friction between two-dimensional titanium carbide Ti2C (MXene) and a silver nanoparticle located on its surface. Numerical experiments were performed within classical molecular dynamics methods using a previously developed scheme for simulations of interactions between MXenes and metal nanoparticles. In the computer experiments performed, both tangential and shear forces were applied to the Ag nanoparticle to initiate its sliding on the surface of the Ti2C MXene. During the simulations, the nanotribological parameters of the studied system, such as the friction force, contact area, friction coefficient, and tangential shear, were computed. It is shown that, for the studied system, the friction coefficient does not depend on the velocity of nanoparticle movement or the contact area. Additionally, the sliding friction of the nanoparticle on the flexible substrate was considered. The latter case is characterized by a larger friction coefficient and contact area due to the formation of wrinkles on the surface of the substrate. Full article
(This article belongs to the Special Issue Advanced Research in 2D Materials)
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15 pages, 8070 KiB  
Article
Low-Temperature Manufacture of Cubic-Phase Li7La3Zr2O12 Electrolyte for All-Solid-State Batteries by Bed Powder
by Taehong Park, Sunho Lee and Dong-Min Kim
Crystals 2024, 14(3), 271; https://doi.org/10.3390/cryst14030271 - 11 Mar 2024
Viewed by 844
Abstract
As the demand for battery technology with enhanced safety and high energy density increases, solid-state batteries are currently attracting attention as a solution to problems such as fire and explosion risks associated with lithium-ion batteries. In this study, experiments were conducted to synthesize [...] Read more.
As the demand for battery technology with enhanced safety and high energy density increases, solid-state batteries are currently attracting attention as a solution to problems such as fire and explosion risks associated with lithium-ion batteries. In this study, experiments were conducted to synthesize and optimize Li7La3Zr2O12 (LLZO), a solid electrolyte that is a key component of lithium-ion batteries with stability and high energy density. Experimental results showed that sintering at a low temperature of 800 °C for 8 h was the optimal synthesis and sintering time. Additionally, the excess lithium-containing bed powder enabled the production of pure cubic-phase LLZO. Through a sintering process that creates a lithium atmosphere on the bottom surface and facilitates lithium replenishment, an additional tunnel was introduced between the specimen and the alumina powder, allowing the bottom surface of the specimen to be exposed to the lithium atmosphere. By manufacturing a uniform cubic electrolyte, the path to manufacturing all-solid-state batteries was opened. These findings provide a new approach to forming cubic-phase LLZO with much higher ionic conductivity than the tetragonal phase at low sintering temperatures. Full article
(This article belongs to the Special Issue Recent Advances and Perspectives in Electrolysis Processes)
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13 pages, 6547 KiB  
Review
Floating Zone Growth of Pure and Pb-Doped Bi-2201 Crystals
by Maria Roslova, Bernd Büchner and Andrey Maljuk
Crystals 2024, 14(3), 270; https://doi.org/10.3390/cryst14030270 - 11 Mar 2024
Viewed by 759
Abstract
In this review, we summarize recent progress in crystal growth and understanding of the influence of crystal structure on superconductivity in pure and Pb-doped Bi2Sr2CuOy (Bi-2201) materials belonging to the overdoped region of high-temperature cuprate superconductors. The crystal [...] Read more.
In this review, we summarize recent progress in crystal growth and understanding of the influence of crystal structure on superconductivity in pure and Pb-doped Bi2Sr2CuOy (Bi-2201) materials belonging to the overdoped region of high-temperature cuprate superconductors. The crystal growth of Bi-2201 superconductors faces challenges due to intricate materials chemistry and the lack of knowledge of corresponding phase diagrams. Historically, a crucible-free floating zone method emerged as the most promising growth approach for these materials, resulting in high-quality single crystals. This review outlines the described methods in the literature and the authors’ synthesis endeavors encompassing Pb-doped Bi-2201 crystals, provides a detailed structural characterization of as-grown and post-growth annealed samples, and highlights optimal growth conditions that yield large-size, single-phase, and compositionally homogeneous Bi-2201 single crystals. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
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14 pages, 4745 KiB  
Article
Mechanical Response of Cu/Sn58Bi-xNi/Cu Micro Solder Joint with High Temperatures
by Xiangxia Kong, Junjun Zhai, Ruipeng Ma, Fenglian Sun and Xuemei Li
Crystals 2024, 14(3), 269; https://doi.org/10.3390/cryst14030269 - 10 Mar 2024
Viewed by 764
Abstract
Sn58Bi solder is considered a promising lead-free solder that meets the performance requirements, with the advantages of good wettability and low cost. However, the low melting point characteristic of Sn58Bi poses a serious threat to the high-temperature reliability of electronic products. In this [...] Read more.
Sn58Bi solder is considered a promising lead-free solder that meets the performance requirements, with the advantages of good wettability and low cost. However, the low melting point characteristic of Sn58Bi poses a serious threat to the high-temperature reliability of electronic products. In this study, Sn58Bi solder alloy based on nickel (Ni) functionalization was successfully synthesized, and the effect of a small amount of Ni on creep properties and hardness of Cu/Sn58Bi/Cu micro solder joints at different temperatures (25 °C, 50 °C, 75 °C, 100 °C) was investigated using a nanoindentation method. The results indicate that the nanoindentation depth of micro solder joints exhibits a non-monotonic trend with increasing Ni content at different temperatures, and the slope of the indentation stage curve decreases at 100 °C, showing that the micro solder joints undergo high levels of softening. According to the observation of indentation morphology, Ni doping can reduce the indentation area and accumulation around the indentation, especially at 75 °C and 100 °C. In addition, due to the severe creep phenomenon at 100 °C, the indentation hardness rapidly decreases. The indentation hardness values of micro solder joints of Cu/Sn58Bi/Cu, Cu/Sn58Bi-0.1Ni/Cu, and Cu/Sn58Bi-0.2Ni/Cu at 100 °C are 14.67 ± 2.00 MPa, 21.05 ± 2.00 MPa, and 20.13 ± 2.10 MPa, respectively. Nevertheless, under the same temperature test conditions, the addition of Ni elements can improve the high-temperature creep resistance and hardness of Cu/Sn58Bi/Cu micro solder joints. Full article
(This article belongs to the Special Issue Welding Dissimilar Materials)
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15 pages, 3416 KiB  
Article
Effect of Traps on the UV Sensitivity of Gallium Oxide-Based Structures
by Vera M. Kalygina, Alexander V. Tsymbalov, Petr M. Korusenko, Aleksandra V. Koroleva and Evgeniy V. Zhizhin
Crystals 2024, 14(3), 268; https://doi.org/10.3390/cryst14030268 - 09 Mar 2024
Viewed by 889
Abstract
Resistive metal/β-Ga2O3/metal structures with different interelectrode distances and electrode topologies were investigated. The oxide films were deposited by radio-frequency magnetron sputtering of a Ga2O3 (99.999%) target onto an unheated sapphire c-plane substrate (0001) in an Ar/O [...] Read more.
Resistive metal/β-Ga2O3/metal structures with different interelectrode distances and electrode topologies were investigated. The oxide films were deposited by radio-frequency magnetron sputtering of a Ga2O3 (99.999%) target onto an unheated sapphire c-plane substrate (0001) in an Ar/O2 gas mixture. The films are sensitive to ultraviolet radiation with wavelength λ = 254. Structures with interdigital electrode topology have pronounced persistent conductivity. It is shown that the magnitude of responsivity, response time τr, and recovery time τd are determined by the concentration of free holes p involved in recombination processes. For the first time, it is proposed to consider hole trapping both by surface states Nts at the metal/Ga2O3 interface and by traps in the bulk of the film. Full article
(This article belongs to the Special Issue 1D and 2D Nanomaterials for Sensor Applications)
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18 pages, 31596 KiB  
Article
Synthesis of BaZrS3 and BaS3 Thin Films: High and Low Temperature Approaches
by Tim Freund, Sumbal Jamshaid, Milad Monavvar and Peter Wellmann
Crystals 2024, 14(3), 267; https://doi.org/10.3390/cryst14030267 - 09 Mar 2024
Viewed by 1068
Abstract
Current research efforts in the field of the semiconducting chalcogenide perovskites are directed towards the fabrication of thin films and subsequently determine their performance in the photovoltaic application. These efforts are motivated by the outstanding properties of this class of materials in terms [...] Read more.
Current research efforts in the field of the semiconducting chalcogenide perovskites are directed towards the fabrication of thin films and subsequently determine their performance in the photovoltaic application. These efforts are motivated by the outstanding properties of this class of materials in terms of stability, high absorption coefficient near the band edge and no significant health concerns compared to their halide counterparts. The approach followed here is to use stacked precursor layers and is adopted from other chalcogenide photovoltaic materials like the kesterites and chalcopyrites. The successful synthesis of BaZrS3 from stacked layers of BaS and Zr and annealing at high temperatures (~1100 °C) with the addition of elemental sulfur is demonstrated. However, the film shows the presence of secondary phases and a flawed surface. As an alternative to this, BaS3 could be used as precursor due to its low melting point of 554 °C. Previously, the fabrication of BaS3 films was demonstrated, but in order to utilize them in the fabrication of BaZrS3 thin films, their microstructure and processing are further improved in this work by reducing the synthesis temperature to 300 °C, resulting in a smoother surface. This work lays the groundwork for future research in the fabrication of chalcogenide perovskites utilizing stacked layers and BaS3. Full article
(This article belongs to the Special Issue Perovskites – New and Old Materials)
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14 pages, 8482 KiB  
Article
A Multiband and Multifunctional Metasurface for Linear and Circular Polarization Conversion in Reflection Modes
by Saima Hafeez, Jianguo Yu, Fahim Aziz Umrani, Wang Yun and Muhammad Ishfaq
Crystals 2024, 14(3), 266; https://doi.org/10.3390/cryst14030266 - 08 Mar 2024
Viewed by 863
Abstract
Multifunctional integrated meta-devices are the demand of modern communication systems and are given a lot of attention nowadays. Most of the research has focused on either cross-polarization conversion (CPC) or linear-to-circular (LP–CP) conversion. However, simultaneously realizing multiple bands with good conversion efficiency remains [...] Read more.
Multifunctional integrated meta-devices are the demand of modern communication systems and are given a lot of attention nowadays. Most of the research has focused on either cross-polarization conversion (CPC) or linear-to-circular (LP–CP) conversion. However, simultaneously realizing multiple bands with good conversion efficiency remains crucial. This paper proposes a multiband and multifunctional dual reflective polarization converter surface capable of converting a linearly polarized (LP) wave into a circularly polarized (CP) wave, in frequency bands of 12.29–12.63 GHz, 16.08–24.16 GHz, 27.82–32.21 GHz, 33.75–38.74 GHz, and 39.70–39.79 GHz, with 3 dB axial ratio bandwidths of 2.7%, 40.15%, 14.6%, 13.76%, and 0.2%, respectively. Moreover, the converter is capable of achieving CPC with a polarization conversion ratio (PCR) that exceeds 95%, within the frequency ranges of 13.10–14.72 GHz, 25.43–26.00, 32.46–32.56 GHz, and 39.14–39.59 GHz. In addition, to identify the fundamental cause of the CPC and LP–CP conversion, a comprehensive theoretical investigation is provided. Furthermore, the surface current distribution patterns at different frequencies are investigated to analyze the conversion phenomena. A sample prototype consisting of 20 × 20 unit cells was fabricated and measured, verifying our design and the simulated results. The proposed structure has potential applications in satellite communications, radar, stealth technologies, and reflector antennas. Full article
(This article belongs to the Special Issue Anisotropic Acoustic Metamaterials)
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18 pages, 4938 KiB  
Article
Automatic Detection of Cast Billet Dendrite Based on Improved Hough Transform
by Yuhan Wang, Qing He and Zhi Xie
Crystals 2024, 14(3), 265; https://doi.org/10.3390/cryst14030265 - 08 Mar 2024
Viewed by 712
Abstract
Primary dendrite information is one of the most important metrics to measure the quality of continuous cast slabs. The contrast of low magnification images is very low under the influence of illumination and sampling devices, so the traditional dendrite detection method has the [...] Read more.
Primary dendrite information is one of the most important metrics to measure the quality of continuous cast slabs. The contrast of low magnification images is very low under the influence of illumination and sampling devices, so the traditional dendrite detection method has the problem of missed detections. We propose an automatic dendrite detection method based on an improved Hough transform, which effectively improves the accuracy and efficiency of primary dendrite detection. By using the local grayscale features of the image, a genetic algorithm-based local contrast enhancement algorithm is proposed. Compared with the traditional contrast enhancement algorithm, it can retain all the information of the dendrites. Combined with the image binarization method based on Hessian matrix, we can obtain more detailed information about the dendrites. According to the continuity and solidification characteristics of dendrites, the Hough transform is improved to extract dendrite information, which effectively reduces the computational cost of the Hough transform. The experimental results show that the method of this paper has versatility, and the error is four pixels compared with the manual method, which can provide a reliable basis for the subsequent judgement of the quality of cast billets. Full article
(This article belongs to the Section Crystalline Metals and Alloys)
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2 pages, 715 KiB  
Correction
Correction: van Delft et al. Two- and Three-Dimensional Superconducting Phases in the Weyl Semimetal TaP at Ambient Pressure. Crystals 2020, 10, 288
by Maarten R. van Delft, Sergio Pezzini, Markus König, Paul Tinnemans, Nigel E. Hussey and Steffen Wiedmann
Crystals 2024, 14(3), 264; https://doi.org/10.3390/cryst14030264 - 08 Mar 2024
Viewed by 579
Abstract
In the original publication [...] Full article
(This article belongs to the Special Issue Synthesis and Characterization of New Superconductors Materials)
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12 pages, 2166 KiB  
Article
Preparation of FeNiCoCrCu Thin Films by Ionized Jet Deposition Method: Determination of Elemental Transfer Coefficients
by Jáchym Lis, Jakub Skočdopole, Petr Jaroš, Jiří Čapek, Karel Trojan, Martin Dráb, Monika Kučeráková, Stanislav Vratislav and Ladislav Kalvoda
Crystals 2024, 14(3), 263; https://doi.org/10.3390/cryst14030263 - 07 Mar 2024
Viewed by 813
Abstract
Investigation of high-entropy alloys in form of bulk samples as well as thin films is currently one of the fastest growing areas in the study of metal alloys. In this paper, a bulk sample of FeNiCoCuCr high-entropy alloy ingot with equimolar composition is [...] Read more.
Investigation of high-entropy alloys in form of bulk samples as well as thin films is currently one of the fastest growing areas in the study of metal alloys. In this paper, a bulk sample of FeNiCoCuCr high-entropy alloy ingot with equimolar composition is prepared by the laboratory arc melting method under an argon atmosphere and used as a source target for deposition of thin films on Si (111) single-crystalline substrates using a novel ionized jet deposition method. The morphology, chemical composition, and real crystalline structure of the target and the prepared layers were characterized by scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy, and X-ray and neutron diffraction methods. Transfer coefficients characterizing the mass transport between the target and the grown film were calculated for each of the constituting metallic elements as the ratio of the atomic concentration found in the prepared film divided by its concentration in the deposition target. The dependence of the obtained transfer coefficients on the IJD acceleration voltage is discussed with respect to the main physical and geometric parameters of the deposition process, and their correlations with the cohesive energy of the elements forming the HEA are proposed. Full article
(This article belongs to the Special Issue Preparation and Properties of Alloys by Physical Vapor Deposition)
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23 pages, 10699 KiB  
Article
Influence of Processing Temperature and Strain Rate on the Microstructure and Mechanical Properties of Magnesium Alloys Processed by Single-Pass Differential Speed Rolling
by Christopher Hale, Zhigang Xu, Svitlana Fialkova, Jessica Rawles and Jagannathan Sankar
Crystals 2024, 14(3), 262; https://doi.org/10.3390/cryst14030262 - 06 Mar 2024
Viewed by 786
Abstract
Magnesium-based alloys show significant promise for widespread applications owing to their lightweight nature and improved mechanical properties achieved through grain refinement via hot rolling. This investigation focuses on Mg-xAl-yCa-zMn (AXM alloys), pre-heated to temperatures of 350, 400, and 450 °C and processed via [...] Read more.
Magnesium-based alloys show significant promise for widespread applications owing to their lightweight nature and improved mechanical properties achieved through grain refinement via hot rolling. This investigation focuses on Mg-xAl-yCa-zMn (AXM alloys), pre-heated to temperatures of 350, 400, and 450 °C and processed via both single-pass differential speed rolling (DSR) and conventional rolling (CR). The key findings reveal the interplay between processing temperature, strain rate during single-pass rolling, and an innovative approach for incorporating varying amounts of Ca, influencing grain size, quantity of dynamic recrystallization (DRX) grains, and overall mechanical properties, including strength and ductility. A noteworthy observation is the positive correlation between an increase in the total reduction during hot rolling and a higher fraction of DRXed grains. This leads to a significant reduction in average grain size, diminishing from 60.3 ± 54.3 μm to 19.5 ± 14.2 μm at 40%, nearly a third the size of T4 grains (the initial homogenized microstructure of the AXM alloys). The resultant material strength experiences a doubling from an average of 125 ± 10.2 MPa (T4) to 260 ± 25.8 MPa (DSR rolled at 40%) for the AXM alloys with potential improvement in the ductility depending on rolling speed conditions. This study also aims to analyze the combination of rolling temperature, rolling speed, thickness reduction, speed difference and Ca content implemented across a wide range of temperatures and strain rates to provide a holistic approach to the processing parameters affecting the microstructure and mechanical properties of AXM alloys. Furthermore, this study provides a deeper understanding of DRX mechanisms, including continuous DRX (CDRX), discontinuous DRX (DDRX), and twinning induced DRX (TDRX), while each of these mechanisms plays a distinct role in the overall enhancement of formability and performance of magnesium alloys. Full article
(This article belongs to the Special Issue Micro-Structure and Mechanical Properties of Alloys)
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