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The outstanding performance of amorphous transition metal phosphides (TMPs) has garnered significant attention in the field of energy storage devices. However, the current approaches for obtaining TMPs require a high phosphidation temperature of over 350 °C, which cause a rise in crystallinity and inferior supercapacitive performance, along with the insufficient utilization of phosphidation agents. In this work, we designed a specially‐made quartz reactor to address this challenge. Using the specially‐designed reactor, the amorphous NiCoP nanosheet array was successfully synthesized on carbon cloth at a relatively low phosphidation temperature of 280 °C. The resulting nanosheet array grown on carbon cloth exhibited a high specific capacity of 338.33 mAh g−1 at a current density of 1 A g−1, along with exceptional cycling stability, retaining 92.3 % of its initial capacity after 1000 cycles. An asymmetric solid‐state hybrid supercapacitor assembled using the prepared amorphous NiCoP@CC‐1 material exhibited a high energy density of 50.98 Wh kg−1 at a power density of 800 W kg−1 while maintaining 92.7 % of initial specific capacity after 5000 cycles. The proposed approach is anticipated to facilitate the use of amorphous TMP materials in the development of high‐performance solid‐state hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

Bulk metallic glasses (BMGs) offer exceptional physical/mechanical properties enabling them to be highly desirable for a variety of applications. Laser powder bed fusion (LPBF) has great promise for producing large and intricate BMG structures. However, using non‐optimal energy distribution in current additive manufacturing machines leads to extensive reheating of previously solidified layers. As a result, the mechanical characteristics can be significantly impacted by structural relaxation and partial crystallization. Here, a tunable advanced laser beam shaping technology is employed to overcome the difficulties originating from non‐optimal energy distribution in current additive manufacturing machines. This study fabricates fully amorphous/dense BMG samples using the shaped laser beam and established optimized atomic‐scale short‐and medium‐range ordering along with improved yield/fracture compressive strength. Formation of a shallow and wide melting pool geometry using the beam shaping allows to increase hatching distances to better control the thermal history introducing improved amorphicity and rejuvenation. This higher rejuvenation and disordering allow for increased atomic mobility, which facilitates the creation and spread of shear bands, thus enhancing the mechanical strength and ductility of the material. The current work demonstrates that BMG parts can be fabricated using flexible beam‐shaping technology allowing to go beyond the capabilities of state‐of‐the‐art additive manufacturing techniques. [ABSTRACT FROM AUTHOR]

The excess entropy ΔS with respect to the maternal crystal has been determined for 18 metallic glasses differing in the mixing entropy ΔSmix. Using these data, thermodynamic fragility mΔS has been determined within the Adam–Gibbs model. It has been shown that mΔS increases with ΔSmix but decreases with increasing ΔS, which reflects the degree of structural disorder in a glass. It has been concluded that the so-called "high-entropy glasses" (i.e., having high ΔSmix) are indeed most ordered and their properties are characterized by the slowest relaxation. [ABSTRACT FROM AUTHOR]

Extensive research has shown that nanolayered structures are capable of suppressing the shear banding in metallic glass in nanoindentation experiments. However, the specific mode and mechanism of the shear banding underneath the indenter remains unknown. Also, the quantification of shear banding-induced strain localization is still a challenge. Herein, the size-dependent shear banding behavior of a CuTiZrNb high-entropy alloy-based nanolayered glass with individual layer thicknesses (h) ranging from 5 to 80 nm was systematically investigated by nanoindentation tests. It was found that the hardness of the designed structure was almost size-independent. Yet, a clear transition in the deformation modes from the cutting-like shear bands to the kinking-like ones was discovered as h decreased to 10 nm. Moreover, multiple secondary shear bands also appeared, in addition to the primary ones, in the sample with h = 10 nm. The transition leads to an obvious strain delocalization, as clearly illustrated by the proposed theoretical model, which is based on the assumption of a pure shear stress state to quantify the shear banding-induced strain localization. The strain delocalization results from the higher density of amorphous/amorphous interfaces that exhibit the change in morphology with a refined layered glass structure. [ABSTRACT FROM AUTHOR]

The production of modern composite materials based on bulk metallic glasses requires knowledge of their primary crystallization processes during heating (BMG). Here, we investigate the structure and crystallization kinetics of a promising modern BMG/B2 nano-composites, a fast-hardened glass-forming alloy Cu50Zr42.5Ti7.5. The complex four-step crystallization of the glass alloy at different heating rates was revealed by differential scanning calorimetry. The process of a crystallization was successfully fully described by a multiverse nonlinear kinetic model, and the kinetic parameters were determined with high accuracy. The best way to describe the four-step crystallization of a glass alloy is the two-branch parallel reaction. The first branch is described by three consecutive n-order autocatalytic reactions. The second branch obeys the Avrami-Erofeev model. The high thermal stability of the amorphous state is evidenced by the average full process crystallization activation energy Ea = 425 kJ mol−1. Analysis of the obtained results and their comparison with available literature data allow us to conclude that the crystallization process in glassy Cu50Zr42.5Ti7.5 alloy (and probably other similar ternary alloys based on binary Cu50Zr50 system) is strongly affected by the structure of initial sample as well as by thermal conditions. The presence of nano-sized inclusion of metastable phases (for example, B2 one) can change the sequence of reaction as well as the structure of phases forming at each stage. [ABSTRACT FROM AUTHOR]

The rational design of multiple metal ions into high-entropy oxide electrode material via a single-step hydrothermal process is applicable to the evolution of oxygen molecules (O2) through simple water electrolysis. Their cost-effectiveness, high performance, and durable nature are the key factors of non-precious high-entropy multiple metal-based electrocatalysts, which can be used as replaceable catalysts instead of precious ones. This article reports a low-temperature synthesis of the cauliflower-type morphology of high-entropy amorphous metal oxides, and their electrochemical performances towards the oxygen evolution reaction (OER) are investigated. The multiple metal ion (Mn2+, Fe3+, Co2+, Ni2+, Cu2+) oxide electrode material shows an acceptable oxygen evolution reaction (OER) with an overpotential of 290 mV at a current density of 10 mA cm−2 and a lower Tafel slope value of 85 mV dec−1, respectively. Moreover, the 20 h durability test with negligible change in overpotential shows the efficacy of the modified electrode material in harsh alkaline media. The observed electrochemical results towards the OER correspond to the amorphous nature of the active material that displayed a cauliflower-type morphology, having a large specific surface area (240 m2 g−1) and providing higher electrochemical active sites as well. Consequently, post-stability characterization studies (such as PXRD, FESEM, TEM, and XPS) provide more information for understanding the post-structural and morphological results of the high-entropy amorphous metal oxide. [ABSTRACT FROM AUTHOR]

The influence of the technological glass-melting parameters of the selected composition in the SrO–Al2O3–P2O3–SiO2–F system on the value of the refractive index and the amount of fluorine remaining in the glass structure post-melting was investigated. The lowering of the melting temperature combined with tableting of the charge [batch] increases fluorine absorption in the glass up to 17 wt.% at the same time, and the value of the refractive index reduction to nD = 1.49. It was experimentally established that in the multicomponent glass selected for glass-ionomer cements with two glass-forming oxides (SiO2 and P2O2) and a high Al2O3 content, each wt.% of fluorine reduces the refractive index by about 3.5 × 10 –4 units. [ABSTRACT FROM AUTHOR]

In this work, the performances of nickel iron layered double hydroxides (LDH) with the nitrate anion at the interlayer (NiFe-NO3) for the manufacture of anodes for lithium-ion batteries have been tested before and after its sintering at different temperatures. After synthesis, the material was thermally analyzed in a range 30–1250 °C, showing a mass loss occurring in three different consecutive steps leading to a total mass decrease of ~30 mass%. Following thermogravimetric analysis (TGA), four samples were prepared by annealing at four different temperatures: one of the four did not undergo a thermal treatment (NiFe-0), while the remaining three were annealed at 250 °C, 360 °C, and 560 °C for 6 h (NiFe-250, NiFe-360, and NiFe-560). All materials where completely characterized via FE-SEM, PXRD, and FT-IR. The pristine LDH material showed some structural and compositional changes for growing temperatures, starting from the typical turbostratic hexagonal structure through a mixture of amorphous metal oxides and finally to the stoichiometric oxides FeNi2O4 and NiO. The as-obtained materials were mixed with carbon black (C65) and sodium alginate and tested as electrodes in Swagelok half cells in LP30 vs. metallic Li to perform CV and GCPL analysis. The electrochemical tests showed that the performances of NiFe-0, both in terms of stability and specific capacity, are not so different from the one of the NiFe-560, even if the Ni mass% in the former is lower than in the NiFe-560. This phenomenon could be explained by assuming a combined mechanism of reaction involving both intercalation and conversion. [ABSTRACT FROM AUTHOR]

In this paper, further in-depth research on chip formation mechanism is conducted on the cutting of metallic glasses. The study of chips contributes to a better understanding of the machining nature of materials, which is of significant importance for improving product quality, reducing energy consumption, and resource utilization. This paper employs a combination of simulation and experimental methods, wihch not only analyzes the mechanism of chip formation in depth, but also investigates the time-varying characteristics of cutting forces. The results indicate that, when comparing simulation with experiments, the average error in cutting forces is 7.62%, and the chip morphology is also quite similar. Observations in the simulation show that as the cutting thickness increases from 7.96 μm to 23.87 μm, the free surface of the chip exhibits serrated features, and the main shear zone of the chip becomes clearer. Cutting forces exhibit periodic variations, with alternating peaks and valleys representing the formation of shear zones in the chip. In the experiment, observed chips displays a wrinkled free surface and a smooth non-free surface, with some chip edges exhibiting a burr phenomenon. By selecting appropriate machining parameters, the generation of secondary shear bands on the free surface was effectively reduced. By observing the chip morphology, it is found that the chip formation is accompanied by the material removal of plasticity and brittleness, which is the result of the combined action of heat, stress, and free volume. It should be considered to lower temperature to reduce the phenomenon of chip adhesion, providing guidance for further optimizing the cutting process of metallic glass. This paper can provide to readers further understanding of the chip formation mechanism in milling metal glass. • 2D finite element modeling was used to simulate the chip formation. • The shear zones appeared on the serrated chips. • The experimental results verified the accuracy of the simulation model. • The chips of BMG have smooth non-free surface and wrinkled free surface. • The serrated chips are the result of heat, stress, and free volume. [ABSTRACT FROM AUTHOR]

Melt treatment is well known to have an important influence on the properties of metallic glasses (MGs). However, for the MGs quenched from different melt temperatures with a quartz tube, the underlying physical origin responsible for the variation of properties remains poorly understood. In the present work, we systematically studied the influence of melt treatment on the thermal properties of a Zr50Cu36Al14 glass-forming alloy and unveiled the microscopic origins. Specifically, we quenched the melt at different temperatures ranging from 1.1 T l to 1.5 T l (T l is the liquidus temperature) to obtain melt-spun MG ribbons and investigated the variation of thermal properties of the MGs upon heating. We found that glass transition temperature, T g, increases by as much as 36 K, and the supercooled liquid region disappears in the curve of differential scanning calorimetry when the melt is quenched at a high temperature up to 1.5 T l. The careful chemical analyses indicate that the change in glass transition behavior originates from the incorporation of oxygen and silicon in the molten alloys. The incorporated oxygen and silicon can both enhance the interactions between atoms, which renders the cooperative rearrangements of atoms difficult, and thus enhances the kinetic stability of the MGs. [ABSTRACT FROM AUTHOR]

The present study examines the impact of a few additives, i.e., silver (Ag), bismuth (Bi), cadmium (Cd), and zinc (Zn) on the kinetics of glass transition and crystallization in glassy Se78Te20Sn2 alloy. This is accomplished by performing the calorimetric experiment in non-isothermal mode. To perceive the metal-induced consequences of Ag, Bi, Cd, and Zn as foreign atoms on the kinematics of glass transition, the glass transition temperature (Tg), Lasocka's glass transition parameters (i.e., A1 and B1), and the glass transition activation energy (Eg) have been calculated. Similarly, we have determined the crystallization temperatures (on-set value To, and peak value Tc) and melting temperature (Peak value Tm), Lasocka's crystallization parameters (i.e., A2 and B2), crystallization rate constant K, and the corresponding activation energy (Ec). Knowing the values of kinetic temperatures of glass transition/ crystallization, the thermal stability, and the glass-forming tendency of ternary Se78Te20Sn2 and quaternary Se76Te20Sn2M2 (M = Ag, Bi, Cd, and Zn) alloys have been also determined. [ABSTRACT FROM AUTHOR]

The viscosity of the Zr56.5Ti13.3Ni13.6Cu9.6S7 bulk glass forming alloy was measured in equilibrium liquid at low and high temperatures. Low temperature measurements were conducted in the vicinity of the glass transition using a thermomechanical analyzer, covering a viscosity range between 109 and 1014 Pa s. The high-temperature experiments were carried out by electromagnetic levitation of a spherical droplet in microgravity during a parabolic flight campaign (TEMPUS), ranging in viscosity from 50 to 800 mPa s. The viscosities were individually modeled using the Vogel–Fulcher–Tammann equation to obtain the fragility parameter D*, which displays a strong liquid behavior of 25.8 and 19.6 for the low and high temperature region, respectively. The Mauro–Yue–Ellison–Gupta–Allan viscosity model was additionally applied, revealing an even more accurate description across the whole temperature range. Next to viscosity, TEMPUS measurements allow the determination of surface tension. With a value of 0.9 N m−1, it is significantly lower than that of other Zr-based metallic glasses without the element sulfur. [ABSTRACT FROM AUTHOR]

Aiming to produce a multifunctional efficient shield for gamma rays and slow neutrons simultaneously, a host glass of 30B2O3–10CaO–10ZnO–50Na2O (BCZNPb1) was prepared and reinforced by increasing the PbO and B2O3 concentrations simultaneously to produce three developed glassy materials containing 10 and 35 (BCZNPb2), 20 and 40 (BCZNPb3), and 30 and 45 (BCZNPb4) mol% of PbO and B2O3. Significant structural changes appeared as a result of the incorporation of PbO and B2O3 into the proposed host glass (BCZNPb1), as the network became overcrowded with the four-coordinate tetrahedral units BO4 and PbO4. The structural changes were extensively studied using X-ray diffraction, density and density-based parameters, and Fourier Transform Infrared spectra. Mechanically, the formed BO4 and PbO4 units increased the covalent bonds and the crosslinking density within the glass network, which reflected positively on the improvement of the elastic moduli (modulus of longitudinal, shear, bulk, and Young) and the hardness of the considered glasses. The results of the optical transmittance spectra showed that the produced glassy materials had high transparency, exceeding 70%. The optical band gap and Urbach energy results confirmed the reduction of disorder within the glass network, which resulted from the formation of BO4 and PbO4 units. The attenuation of gamma rays and slow neutrons results showed a significant improvement with increasing the PbO and B2O3 concentrations, as the required half-value layers to attenuate gamma rays decreased by 61.540, 57.790, and 56.699% for the studied gamma ray energies of 661.64, 1173.23, and 1132.51 keV at 30 mol% of PbO (BCZNPb4 glass), respectively, while the required half-value layer for slow neutrons decreased by 61.409% at 45 mol% of B2O3 (BCZNPb4 glass). Accordingly, the produced BCZNPb4 glass has suitable mechanical properties, high transparency, and high attenuation efficiency for gamma rays and slow neutrons, making it a desirable shield in many nuclear domains. [ABSTRACT FROM AUTHOR]

Current study is aimed at evaluating Eu-doped barium-bismuth phosphate glasses as potential visible laser medium operating in red spectral region. Samples with composition x Eu 2 O 3 –20BaO–20Bi 2 O 3 -1.5Al 2 O 3 -(58.5- x)P 2 O 5 (x = 0, 0.5, 1.0, 1.5) were prepared using melt-quenching technique. Physical parameters, such as, density, molar volume, oxygen packing density, rare-earth ion concentration, inter-nuclear distance and field strength were evaluated. Thermal stability of prepared glass samples was observed using Thermogravimetric Analysis (TG). The influence of rare-earth oxide content on glass transition temperature T g , crystallization temperature T c and onset of crystallization temperature T x was studied through Differential Thermal Analysis (DTA). Optical band gap and related optical properties were evaluated from absorption spectrum recorded in the range 225–1000 nm. Judd-Ofelt parameters, branching ratio, radiative lifetime, emission cross-section and other radiative properties were evaluated from photoluminescence emission spectrum in the range 500–750 nm. High value of emission cross-section observed for transition 5D 0 →7F 4 in 0.5-EuBiPBa sample signifies its potential use in the development of visible lasers. [ABSTRACT FROM AUTHOR]

Certain metals produce passive oxide film layers during use which are closely related to their corrosion resistance. The properties of the oxide film are strongly influenced by the oxygen content of the surrounding environment. This study aims to examine the impact of dissolved oxygen concentration on the corrosion and passive oxide film formed on Fe-based metallic glass coatings. In deoxygenated solutions, the coating was highly susceptible to corrosion, while exhibiting the highest corrosion potential in oxygenated solutions due to the formation of a dense oxide film. The impedance of the passive film was notably influenced by the presence of dissolved oxygen. In deoxygenated solutions, the impedance remained stable and at a minimum level. However, in oxygenated solutions, the impedance exhibited a significant increase accompanied by rapid film growth. The carrier concentration in the passive film remained low and constant in deoxygenated solutions but decreased in oxygenated ones. The composition of the passive film varied with dissolved oxygen concentration, leading to FeOOH formation in deoxygenated solutions and to the increase in Cr 2 O 3 /Cr(OH) 3 ratio in oxygenated environments. Moreover, deoxygenated solutions slowed down the film growth rate, while oxygenated ones were conducive to the fast development of films, affecting their protective ability. [ABSTRACT FROM AUTHOR]

Entropy production in quasi-isentropic compression (QIC) is critically important for understanding the properties of materials under extreme conditions. However, the origin and accurate quantification of entropy in this situation remain long-standing challenges. In this work, a framework is established for the quantification of entropy production and partition, and their relation to microstructural change in QIC. Cu50Zr50 is taken as a model material, and its compression is simulated by molecular dynamics. On the basis of atomistic simulation-informed physical properties and free energy, the thermodynamic path is recovered, and the entropy production and its relation to microstructural change are successfully quantified by the proposed framework. Contrary to intuition, entropy production during QIC of metallic glasses is relatively insensitive to the strain rate γ ̇ when γ ̇ ranges from 7.5 × 108 to 2 × 109/s, which are values reachable in QIC experiments, with a magnitude of the order of 10−2kB/atom per GPa. However, when γ ̇ is extremely high (> 2 × 1 0 9 / s), a notable increase in entropy production rate with γ ̇ is observed. The Taylor–Quinney factor is found to vary with strain but not with strain rate in the simulated regime. It is demonstrated that entropy production is dominated by the configurational part, compared with the vibrational part. In the rate-insensitive regime, the increase in configurational entropy exhibits a linear relation to the Shannon-entropic quantification of microstructural change, and a stretched exponential relation to the Taylor–Quinney factor. The quantification of entropy is expected to provide thermodynamic insights into the fundamental relation between microstructure evolution and plastic dissipation. [ABSTRACT FROM AUTHOR]

The document provides a comprehensive list of upcoming conferences and events related to X-ray spectrometry, chemical analysis, and materials research. These events will take place in different locations worldwide from 2024 to 2028. Notable conferences mentioned include the Nano tech 2024 conference in Tokyo, the APS March Meeting 2024 in Minneapolis, the ACS Spring 2024 conference in New Orleans, and the European Conference on X-ray Spectrometry 2024 in Athens. Researchers and professionals interested in these fields can use this list to find relevant conferences and meetings to attend or gather information from, fostering collaboration and knowledge sharing. [Extracted from the article]

It was established that the change in the structure of the amorphous metal alloy (AMA) as a result of heat treatment of the amorphous metal alloy Al87Gd5Ni4Fe4 at T = 645±1 K significantly affects the decolorization of the dye Basic Blue 6/Mendola Blue (BB6/MB) at pH = 1.7±0.3. The MB solution with a concentration of 4.39 µM was decolorized by 99% within 27 hours, in the case of annealed AMAs for 30, 45, 60 min., which is 3.8 times more effective than in the case of as-cast AMAs. A change in the AMA structure due to annealing was established by X-ray analisys; kinetic analysis was performed based on experimental data and the kinetic parameters (kobs, t1/2, ksa, etc.) of the MB decolorization reaction were calculated. The surface of AMAs after reaction with aniline dye MB and the proposed scheme of decolorization of aniline dye MB using AMAs Al87Gd5Ni4Fe4 were suggested. [ABSTRACT FROM AUTHOR]

The fast dynamic properties of the surface of metallic glasses (MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth. [ABSTRACT FROM AUTHOR]

Structure of metallic glasses fascinates as the generic amorphous structural template for ubiquitous systems. Its specification necessitates determination of the complete hierarchical structure, starting from short-range-order (SRO) → medium-range-order (MRO) → bulk structure and free volume (FV) distribution. This link has largely remained elusive since previous investigations adopted one-technique-at-a-time approach, focusing on limited aspects of any one domain. Reconstruction of structure from experimental data inversion is non-unique for many of these techniques. As a result, complete and precise structural understanding of glass has not emerged yet. In this work, we demonstrate the first experimental pathway for reconstruction of the integrated structure, for Zr 67 Ni 33 and Zr 52 Ti 6 Al 10 Cu 18 Ni 14 glasses. Our strategy engages diverse (× 7) multi-scale techniques [XAFS, 3D-APT, ABED/NBED, FEM, XRD, PAS, FHREM] on the same glass. This strategy complemented mutual limitations of techniques and corroborated common parameters to generate complete, self-consistent and precise parameters. Further, MRO domain size and inter-void separation were correlated to identify the presence of FV at MRO boundaries. This enabled the first experimental reconstruction of hierarchical subset: SRO → MRO → FV → bulk structure. The first ever image of intermediate region between MRO domains emerged from this link. We clarify that determination of all subsets is not our objective; the essence and novelty of this work lies in directing the pathway towards finite solution, in the most logical and unambiguous way. [ABSTRACT FROM AUTHOR]

The mechanical properties of metallic nanoglasses (NGs) strongly depend on the average size of glassy grains (Davg). Nevertheless, current knowledge on the effects of sizes of glassy grains is incomplete for the mechanical properties of NGs. Herein, ZrxCu100-x (25 ≤ x ≤ 75) nanoglasses containing glassy grains with different chemical compositions, i.e., the heterogeneous NGs (HNGs), are investigated by molecular dynamics simulation, and the relation between ultimate tensile strength (UTS) and Davg is determined. Specifically, the UTS decreases with decreasing Davg in Zr-Cu HNGs when Davg < 10 nm, mainly resulting from the increased volume fraction of glass-glass interfaces, while UTS would follow the Hall-Petch like relation for Zr-Cu HNGs when Davg > 10 nm, which is closely related to glassy grains with compositions dominated by Zr atoms. This study provides a deep insight into the mechanical property dependence on grain size in the HNGs, which could be a novel strategy in resolving the issue of strength-ductility tradeoff in NGs. [ABSTRACT FROM AUTHOR]

The surface diffusion kinetics on a Pd77.5Cu6Si16.5 metallic glass is measured using a scratch smoothing method in the range of 107–57 K below the glass transition temperature. Within this temperature range, the surface diffusion coefficients are determined to vary between (8.66 ± 0.80) × 10−19 and (5.90 ± 0.60) × 10−18 m2 s−1. The corresponding activation energy is 0.93 ± 0.18 eV, which is about half the value for bulk diffusion. These measurements also corroborate the correlation between enhanced surface diffusion and liquid fragility in glasses. [ABSTRACT FROM AUTHOR]

There has been a growing effort to replace manual extraction of data from research papers with automated data extraction based on natural language processing, language models, and recently, large language models (LLMs). Although these methods enable efficient extraction of data from large sets of research papers, they require a significant amount of up-front effort, expertise, and coding. In this work, we propose the ChatExtract method that can fully automate very accurate data extraction with minimal initial effort and background, using an advanced conversational LLM. ChatExtract consists of a set of engineered prompts applied to a conversational LLM that both identify sentences with data, extract that data, and assure the data's correctness through a series of follow-up questions. These follow-up questions largely overcome known issues with LLMs providing factually inaccurate responses. ChatExtract can be applied with any conversational LLMs and yields very high quality data extraction. In tests on materials data, we find precision and recall both close to 90% from the best conversational LLMs, like GPT-4. We demonstrate that the exceptional performance is enabled by the information retention in a conversational model combined with purposeful redundancy and introducing uncertainty through follow-up prompts. These results suggest that approaches similar to ChatExtract, due to their simplicity, transferability, and accuracy are likely to become powerful tools for data extraction in the near future. Finally, databases for critical cooling rates of metallic glasses and yield strengths of high entropy alloys are developed using ChatExtract. Efficient data extraction from research papers accelerates science and engineering. Here, the authors develop an automated approach which uses conversational large language models to achieve high precision and recall in extracting materials data. [ABSTRACT FROM AUTHOR]

In the absence of periodicity, the structure of glass is ill-defined, and a large number of structural states are found at similar energy levels. However, little is known about how these states are connected to each other in the potential energy landscape. We simulate mechanical relaxation by molecular dynamics for a prototypical C u 64.5 Z r 35.5 metallic glass and follow the mechanical energy loss of each atom to track the change in the state. We find that the energy barriers separating these states are remarkably low, only of the order of 1 meV, implying that even quantum fluctuations can overcome these potential energy barriers. Our observation of numerous small ripples in the bottom of the potential energy landscape puts many assumptions regarding the thermodynamic states of metallic glasses into question and suggests that metallic glasses are not totally frozen at the local atomic level. Little is known about how the states in glass are connected to each other. Here, the authors perform molecular dynamics simulation of relaxation in a prototypical metallic glass to show that the energy barriers separating these states are very low, and even be overcome by quantum fluctuations. [ABSTRACT FROM AUTHOR]

• Cu-based MGs as electrodes for dye degradation exhibit high catalytic performance. • The degradation efficiency is 96% within 40 min using Cu 55 Zr 45 MG electrodes. • The Cu 55 Zr 45 MG electrodes can degrade the dye solution with different pH values. • Electrochemical action tends to the generation of the active substances. Metallic glasses have received a lot of attention on wastewater treatment due to their unique atomic structure, and the use of metallic glasses as electrodes has produced unexpected electrocatalytic degradation effects for many pollutants through combining with electrochemical technology. However, it still is a formidable challenge to find a metallic glass electrode material with both efficient and clean for the catalytic degradation of pollutants. In this work, the Cu 55 Zr 45 metallic glassy ribbons are used as an electrode to degrade azo dyes and show the excellent degradation effect, which can reach 95.6% within 40 min. In the degradation process, almost no additives are produced and Cu 55 Zr 45 metallic glassy ribbons have excellent effects under different pH conditions. Meanwhile, it exhibits good stability for degradation efficiency during the 8 cycle degradation tests of the amorphous alloy electrode. When the copper nanoparticles are exposed on the surface of the ribbons, the oxidized copper obtained synergistically produce activated radicals is the primary degradation mechanism, where the auxiliary degradation mechanisms include electron transfer and the promotion of active chlorine. This research develops a new type of electrode material for wastewater treatment, and the economy and high efficiency of Cu 55 Zr 45 metallic glass endow it the expandable functional applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The formation of the α-Al2O3 scale on reactive element (RE)-doped FeCrAl alloys is commonly believed to be primarily caused by inward oxygen transport along grain boundaries. However, this study suggests that metal ion outward diffusion also plays a role in the development of the oxide scales and their microstructural characteristics. The study examines the oxidation behavior and grain boundary outward diffusion of iron-chromium alloys containing ~ 10 at% aluminum and ~ 22 at% chromium, doped with an over-critical concentration of REs, i.e., Zr and Hf. All samples were investigated after thermal exposure at 1100 °C by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atom probe tomography (APT). As a result of the overdoping, a considerable increase in oxide growth, an increase in the depth of internal oxidation, and RE-oxide formation near and at oxide grain boundaries (GBs) were observed as a consequence of increased inward and outward diffusion. The effect of overdoping manifests itself differently depending on the RE type and amount due to different solubility, ionic size, and electronic structure of alumina. The sample with Zr retained the adhesion of alumina to the alloy after the first and second thermal exposure, while Hf overdoping resulted in severe spallation after the second thermal exposure. [ABSTRACT FROM AUTHOR]

The current work concerned the thermal characteristic of Se0.75−xTe0.25Agx (0 ≤ x ≤ 0.1) chalcogenide glasses. Under non-isothermal conditions, differential scanning calorimetry has been used to evaluate the thermal stability of these compositions throughout the temperature identification of the glass transition, Tg, the initial crystallization temperature, Tin, the peak crystallization rate, Tp, and the melting temperature, Tm. Also, the kinetic factor Kr(T) is specified as a further indication of thermal stability. It was found that the Se0.71Te0.25Ag0.04 has the greatest capacity to form glass and the greatest glass thermal stability between these compositions. These findings have been explained using the average coordination numbers of the tested compositions. Also, in this work, we studied the crystallization kinetic of Se0.75−xTe0.25Agx (0 ≤ x ≤ 0.1) thick films via measuring the sheet resistance, Rs whose thickness is 1000 nm at heating rate 5 K min−1, in the 300–630 K temperature range. Two significant regions might be detected in the sheet resistance curve using this range and by considering how sheet resistance is derived according to temperature, one crystallization area is clearly present for the investigated films. The Avrami index was measured for both alloys and thick films. [ABSTRACT FROM AUTHOR]

In this study, a series of barium-boro-tellurite glass hosts with varying concentration of Dy2O3 doping (0 to 1.25 mol%) were made by melt-quenching method. A study was conducted to investigate how Dy2O3 dopants affect the physical and spectroscopic traits of glasses. Raw materials including barium oxide (BaO), tellurium dioxide (TeO2), boron oxide (B2O3), and dysprosium oxide (Dy2O3) were used to produce these glasses. XRD patterns of the samples showed a broad hump and absence of long-range periodic lattice arrangements, indicating their amorphous nature. The Raman spectral analyses displayed the various vibration modes where the most intense band caused by BaO vibrations at 300 cm-1 and 450 cm-1 corresponding to the symmetric stretching vibration mode of Te–O–Te intra-chain bridges. The peak at 750 cm-1 was due to TeO4 and Te-O-Te vibration modes. The value of optical band gap energy was decreased from 3.155 to 2.1894 eV and then increase at higher Dy2O3 level (0.75 to 1.25 mol%). At Dy3+ contents between 0.25 to 1.25 mol% seven absorption bands were observed at 390, 424, 452, 750, 797, 895 and 1092 nm due to the electronic transitions in Dy3+. The glass refractive indices were raised from 2.3563 to 2.6584 and then decreased at higher Dy2O3 contents which was mainly because of the generation of more bridging oxygen (BO) in the glass matrix. The value of glass electronic polarizability and oxide ions polarizability calculated using LorentzLorenz equation showed a decrease with the rise of Dy2O3 contents, which was ascribed to the presence of fewer non-bridging oxygen (NBO). The optical basicity of the proposed glass hosts was calculated using Duffy and Ingram equation which was decreased with the increase of doping contents. In addition, the optical transmission was increased and reflection loss was reduced with increasing Dy+3 levels. The value of metallization parameter below 1 proved the true amorphous nature of the prepared samples. All the glasses revealed blue and yellow photoluminescence emission peaks due to 4F9/2→ 6H15/2, and 4F9/2 →6H13/2 transitions in Dy3+, respectively. The proposed glass compositions may be beneficial for the advancement of solid-state lasers. [ABSTRACT FROM AUTHOR]

Due to their outstanding elastic limit, biocompatible Ti-based bulk metallic glasses (BMGs) are candidate materials to decrease the size of medical implants and therefore reduce their invasiveness. However, the practical use of classical Ti-BMGs in medical applications is in part hindered by their high copper content: more effort is thus required to design low-copper Ti-BMGs. In this work, in line with current rise in AI-driven tools, machine learning (ML) approaches, a neural-network ML model is used to explore the glass-forming ability (GFA) of unreported low-copper compositions within the biocompatible Ti-Zr-Cu-Pd system. Two types of models are trained and compared: one based on the alloy composition only, and a second based on various features derived from the alloying elements. Contrary to expectation, the predictive power of both models in evaluating GFA is similar. The compositional space identified by ML as promising is experimentally assessed, finding unfortunately low GFA. These results indicate that the ML approach may be premature for specific composition tuning of amorphous metallic materials. We emphasise that the development of ML tools in GFA prediction requires an improvement of the dataset, in terms of homogeneity, size and GFA descriptors, which must be supported by increased reporting of high-quality experimental GFA measurements, both positive and negative. Biocompatible Ti-based bulk metallic glasses (BMGs) are candidate materials for use in the next generation of minimally invasive dental implants where improved mechanical properties, such as high strength are required. Despite promising in vitro/vivo evaluations, implementation of alloys for practical applications is partly hindered by the presence of copper as the main alloying element. Recent studies have presented AI-guided and machine learning strategies as appealing approaches to understand and describe the glass forming ability (GFA) of BMG-forming compositions. In this work, we employ and evaluate the capacity of a machine-learning model to explore low-copper compositional spaces in the biocompatible Ti-Zr-Cu-Pd system. Our results highlight the limits of such a computational approach and suggest improvements for future designing routes. [Display omitted] [ABSTRACT FROM AUTHOR]

• Advancements in spark plasma sintering (SPS) for Mg and its alloys are introduced. • Effects of processing/material conditions on structural features are presented. • Particle nanostructuring and composites for controlling degradation are explored. • An overview of the latest industrial advancements of SPS Mg is thoroughly reviewed. Within the past ten years, spark plasma sintering (SPS) has become an increasingly popular process for Mg manufacturing. In the SPS process, interparticle diffusion of compressed particles is rapidly achieved due to the concept of Joule heating. Compared to traditional and additive manufacturing (AM) techniques, SPS gives unique control of the structural and microstructural features of Mg components. By doing so, their mechanical, tribological, and corrosion properties can be tailored. Although great advancements in this field have been made, these pieces of knowledge are scattered and have not been contextualized into a single work. The motivation of this work is to address this scientific gap and to provide a groundwork for understanding the basics of SPS manufacturing for Mg. To do so, the existing body of SPS Mg literature was first surveyed, with a focus on their structural formation and degradation mechanisms. It was found that successful Mg SPS fabrication highly depended on the processing temperature, particle size, and particle crystallinity. The addition of metal and ceramic composites also affected their microstructural features due to the Zener pinning effect. In degradative environments, their performance depends on their structural features and whether they have secondary phased composites. In industrial applications, SPS'd Mg was found to have great potential in biomedical, hydrogen storage, battery, automotive, and recycling sectors. The prospects to advance the field include using Mg as a doping agent for crystallite size refinement and using bulk metallic Mg-based glass powders for amorphous SPS components. Despite these findings, the interactions of multi-composites on the processing-structure-property relationships of SPS Mg is not well understood. In total, this work will provide a useful direction in the SPS field and serve as a milestone for future Mg-based SPS manufacturing. [ABSTRACT FROM AUTHOR]

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Zr57Cu15Ni10Nb5 (more known as Vit-106) is a promising zirconium-based alloy with a high glass-forming ability, and belongs to the so-called bulk metallic glasses (BMG). Workpieces with a size of around one centimeter in all three dimensions can be obtained from a BMG alloy by casting. However, further increasing the cast size decreases the cooling rate and thus induces crystallization. Selective laser melting (SLM) is a well-known technique to overcome size limitations for BMGs because a workpiece is built by the addition of multiple melt portions in which the cooling rate is kept above the critical one. Currently, BMG parts obtained by SLM suffer from partial crystallization. The present work studies the influence of SLM process parameters on the partial crystallization of Vit-106 by metallography and the influence of the microstructure on mechanical properties by microhardness and wear resistance testing. Submicron crystalline inclusions are observed in an amorphous matrix of a Vit-106 alloy obtained by SLM. The size and the concentration of the inclusions can be controlled by varying the laser scanning speed. It is shown that submicron crystalline inclusions formed in the amorphous matrix during SLM can favorably affect microhardness and wear resistance. [ABSTRACT FROM AUTHOR]

Amorphous solids are non‐equilibrium states of matter that lack long‐range structural order, and are recognized as key materials in electronics. Although 2D van der Waals materials have been intensively studied in the wide field of materials science, their amorphous states have been less studied experimentally. Here, a van der Waals ferromagnetic semiconductor CrGeTe3 transforms into an amorphous ferromagnetic metal upon irradiation with high‐energy Xe ions. Notably, the Curie temperature of the amorphous state reaches 200 K, which is three times higher than that of the crystalline phase. The anomalous Hall conductivity in the amorphous phase is governed by the extrinsic skew‐scattering mechanism, although conventional theory predicts that skew scattering is dominant only in ultra‐clean ferromagnetic metals. The present results call for a new theory of the anomalous Hall effect in highly disordered ferromagnetic conductors. Moreover, the unique change in magnetic and transport properties due to amorphization of the van der Waals material is expected to open up a new research field in materials science. [ABSTRACT FROM AUTHOR]

Thin and flexible materials that can provide efficient electromagnetic interference (EMI) shielding are urgently needed, particularly those that can be rapidly processed and withstand harsh environments. Cobalt‐based metallic glasses stand out as prime candidates due to their excellent soft magnetic properties, satisfactory shielding features, and mechanical properties. Herein, a recently developed technique is used to fabricate metallic glass microfibers from Co66Fe4Mo2Si16B12 alloy. The produced microfibers are characterized for their size and uniformity by scanning electron microscopy and their amorphous structure is confirmed by X‐ray diffraction (XRD) and differential scanning calorimetry (DSC). The cobalt‐based metallic glass microfibers show an EMI shielding factor that reaches five in the static regime and obtains an up to 25‐fold increase of the attenuation constant in the Ku frequency band. This performance originates from the combination of soft magnetic properties and excellent electrical conductivity. In addition, the flexible microfibers exhibit excellent hardness and elasticity making them suitable for EMI shielding of complex geometries. Their hardness and elastic modulus are measured by nanoindentation to be 11.31 ± 0.60 GPa, and 110.54 ± 11.24 GPa, respectively. [ABSTRACT FROM AUTHOR]

Ti-based bulk metallic glasses are promising materials for metallic bone implants, mainly due to their mechanical biofunctionality. A major drawback is their limited corrosion resistance, with high sensitivity to pitting. Thus, effective surface treatments for these alloys must be developed. This work investigates the electrochemical treatment feasibility of nitric acid (HNO3) solution for two bulk glass-forming alloys. The surface states obtained at different anodic potentials are characterized with electron microscopy and Auger electron spectroscopy. The corrosion behavior of the treated glassy alloys is analyzed via comparison to non-treated states in phosphate-buffered saline solution (PBS) at 37 °C. For the glassy Ti47Zr7.5Cu38Fe2.5Sn2Si1Ag2 alloy, the pre-treatment causes pseudo-dealloying, with a transformation from naturally passivated surfaces to Ti- and Zr-oxide nanoporous layers and Cu-species removal from the near-surface regions. This results in effective suppression of chloride-induced pitting in PBS. The glassy Ti40Zr10Cu34Pd14Sn2 alloy shows lower free corrosion activity in HNO3 and PBS due to Pd stabilizing its strong passivity. However, this alloy undergoes pitting under anodic conditions. Surface pre-treatment results in Cu depletion but causes enrichment of Pd species and non-homogeneous surface oxidation. Therefore, for this glassy alloy, pitting cannot be completely inhibited in PBS. Concluding, anodic treatments in HNO3 are more suitable for Pd-free glassy Ti-based alloys. [ABSTRACT FROM AUTHOR]

The physical properties of low alkali content tellurite glasses of composition xM2O.(1−x)TeO2 (0≤x≤0·35) have been previously collected in this laboratory. The twin-roller rapid quenching technique (cooling rate>105°C/s), used within a nitrogen environment, successfully and significantly extended the glass-forming range in the lithium and sodium tellurite systems. The upper range for modification has been extended from x=0·35 to 0·80 and up to x=0·625 for the lithium and sodium systems, respectively. In the K, Rb and Cs tellurites, the glass forming ranges were not increased. Glass transition temperature (Tg), crystallisation temperature (Tx), density, molar volume, packing fraction, ionic conductivity and Raman spectra were obtained for these glasses. These results showed structural changes as a function of composition and carbonate retention in the glasses as the amount of alkali modifier increased above x=0·5. [ABSTRACT FROM AUTHOR]

Wires of a Cu--3.8 wt% Zr alloy were produced by conform extrusion followed by wire drawing up to 0.2mm in diameter (S wire), or by conform extrusion and subsequent annealing during wire drawing up to 0.2mm (IA wire). The effects of microstructure on the strength and electrical conductivity of the S and IA wires were investigated. The severely drawn S and IA wires had a mixed microstructure consisting of a Cu parent phase with fine grains, fibrous eutectics elongated along the drawing direction, and granular eutectics. The 0.2% proof stress (·0.2) and tensile strength (·u) of the S and IA wires increased monotonically with increasing drawing ratio (©). The S wire with © = 7.8 exhibited large values of ·0.2 = 1080MPa and ·u = 1320 MPa. The S and IA wires having the mixed microstructure are strengthened primarily by high density of dislocations and grain refinement in the Cu phase and by the presence of fibrous and granular eutectics. The electrical conductivity (E) of the S wire increased in the early stage of wire drawing and then began to decrease, dropping to 42% IACS at © = 7.8. The increase in E is caused by refining of the eutectics, which was formed during casting, toward the granular or fibrous form. The E value of the IA wire after annealing was high, 72%IACS, and then decreased as © increased. Values of E of the S and IA wires with the mixed microstructure was estimated by applying rules of mixtures. The estimated values of E are in agreement with the measured values of E. It is shown that the presence of the fibrous and granular eutectics significantly increases the electrical conductivity. [ABSTRACT FROM AUTHOR]

A kind of bulk metallic glass composites (BMGCs) with ex situ tungsten (W) particles and in situ dendrites were designed and successfully prepared through infiltrating Ti40.9Zr30.4Nb4.2Cu7Ni1.7Be15.8 (at.%) melt into the W preforms at different temperatures of 1103-1243 K. X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements show the dendrites change from single bcc phase to the mixture crystals along with the significant increase in the volume fraction due to the more W dissolution when the casting temperature increases over 1183 K. With such the microstructural evolution, the mechanical properties change significantly from high strength and ductility along with work hardening capacity to the reduced strength and ductility along with work softening capacity. The samples prepared at 1123 K exhibit the optimal mechanical properties including the yield strength of ~ 1670 MPa, the maximum fracture strength of ~ 2080 MPa and the plastic strain of ~ 26%, which is attribute to the cooperative deformation mechanism between W particles and in situ BMGC matrix. These findings deepen the understanding of the cooperative deformation of composites containing the multiple phases and shed light on design BMGCs for specific application. [ABSTRACT FROM AUTHOR]

Improving the quality of the manufacturing process is an important goal of professional technicians. This study systematically explored the key success factors in the product-forming ability and visual optimization of 3D forming in the clay-shaping process through actual manufacturing and implementation. The purpose of this study was to identify the forming technology and technical indicators that can successfully achieve a high degree of completeness and maturity in the manufacturing process, increasing the shaping performance of the end products and enabling the evaluation of optimization. In this study, we evaluated soil shaping, material use, the manufacturing process, and product forming. The key success factors were studied and analyzed via expert interviews. The research and analysis were summarized into 4 dimensions with 48 sub-dimensions. These included: (1) soil material, with 12 sub-dimensions; (2) the design concept, with 12 sub-dimensions; (3) the prototype process, comprising 12 sub-dimensions; and (4) kiln firing, comprising 12 sub-facets. A research team composed of 13 scholars and experts conducted three surveys on the evaluation dimensions of the Delphi technique. They analyzed the mean (M), mode (Mo), and standard deviation (SD) of various dimension options. They used the Kolmogorov–Smirnov one-sample test research and analysis to analyze the appropriateness and consistency of the survey results. The results of this study showed that 15 sub-dimensions met the appropriateness and consistency conditions, based on which 15 key factors were established. The results of this study provide reference indicators for the manufacturing process, forming process, and forming technology optimization quality for follow-up research. [ABSTRACT FROM AUTHOR]

In glass molding to produce biochips with micro holes, cavities, and channels, it is important to machine micro molds. This study presents a novel process for fabricating micro pin arrays on carbon graphite, one of the glass molding materials. The micro pin array was used as a mold to fabricate a glass-based micro hole array. Using conventional micro endmill tools, machining micro-cylindrical pins requires complex toolpaths and is time-consuming. In order to machine micro pin arrays with high efficiency, a micro eccentric tool was introduced. Micro pin arrays with a diameter of 200 µm and a height of 200 µm were easily fabricated on graphite using the micro eccentric tool. In the machining of micro pin arrays using eccentric tools, the machining characteristics such as cutting force and tool wear were investigated. [ABSTRACT FROM AUTHOR]

Shear bands are very common microstructural features in metals undergoing high plastic deformation. In processes like cold rolling, shear banding plays an essential role in obtaining the desired crystallographic texture. However, the exact deformation mechanism of shear bands is yet to be fully understood. This work explores the modeling of shear band formation and the effect of orientation of the crystal, prior to the deformation, through single crystal simulations. The effect of crystal orientation and crystallographic anisotropy on shear band formation is studied using a gradient damage model coupled with plasticity and crystallographic information. It is observed that the orientation affects shear band thickness and the strain at which shear bands are formed. [ABSTRACT FROM AUTHOR]

Molecular dynamics computer simulations of a polydisperse soft-sphere model under shear are presented. The starting point for these simulations are deeply supercooled samples far below the critical temperature, Tc, of mode coupling theory. These samples are fully equilibrated with the aid of the swap Monte Carlo technique. For states below Tc, we identify a lifetime τlt that measures the time scale on which the system can be considered as an amorphous solid. The temperature dependence of τlt can be well described by an Arrhenius law. The existence of transient amorphous solid states below Tc is associated with the possibility of brittle yielding, as manifested by a sharp stress drop in the stress–strain relation and shear banding. We show that brittle yielding requires, on the one hand, low shear rates and, on the other hand, the time scale corresponding to the inverse shear rate has to be smaller or of the order of τlt. Both conditions can only be met for a large lifetime τlt, i.e., for states far below Tc. [ABSTRACT FROM AUTHOR]

The microstructural evolutions and dynamic properties of the Zr77Rh23 alloy during the rapid cooling process have been studied by molecular dynamics (MD) simulations using tight-binding (TB) potential. The total pair distribution functions [or structure factors, S(q)], g(r), calculated at different temperatures are in good agreement with the ab initio MD (AIMD) simulation (or experimental) results. The splitting in the second peak of all g(r) is notable for the formation and development of a medium-range order (MRO) in the Zr77Rh23 system. Moreover, the total number of atoms determined from TB-MD simulations at 300 K is also consistent with the number of atoms of the three shells for the Bergman-type MRO cluster and AIMD simulation results. By analyzing the structure of the system with methods such as the Honeycutt–Andersen index, Voronoi tessellation, and bond-angle distribution, it has been shown that the icosahedron short-range order (SRO) increases upon cooling. The dominant short-range structure in Zr77Rh23 metallic glass is found to consist mostly of perfect and distorted icosahedral clusters. The findings show that, for all temperatures, Zr atoms have greater mobility than Rh atoms. The critical temperature Tc estimated from fitting the mode-coupling theory equation is ∼993 K. A dynamic crossover is observed at temperatures around Tc. The present findings contribute to understanding the nature of the atomic local structures of the Zr77Rh23 alloy during the cooling process and the formation of SRO/MROs in metallic glasses. [ABSTRACT FROM AUTHOR]

The glass formation ability of an alloy depends on two competing processes: glass-transition, on one hand, and crystal nucleation and growth, on the other hand. While these phenomena have been widely studied before in nearly equiatomic Cu–Zr alloys, studies are lacking for solute/solvent-rich ones. In the present work, molecular dynamics simulations show that the addition of a small amount of Zr (1–10 at. %) to Cu drastically increases the incubation time and slows down crystal growth, thus, leading to an improved glass forming ability. The crystal nucleation and growth processes of a competing face-centered cubic (FCC) Cu crystalline phase are analyzed in detail. In particular, the values of the critical cooling rate, incubation period for crystallization, and growth rate of FCC Cu crystals in these Cu-rich alloys are obtained. The growth of a supersaturated FCC Cu solid solution is found to be polymorphic at the interface (except for alloys with 9 and 10 at. % Zr) though a Zr concentration gradient is observed within growing crystals at high enough Zr content. The crystal growth rate before crystal impingement is nearly constant in all alloys, though it decreases exponentially with the Zr content. Crystallization kinetics are also analyzed within the existing theories and compared with the experimental values available in the literature. [ABSTRACT FROM AUTHOR]

The apparent relationship between Poisson's ratio and fracture energy has been used to guide the discovery of ductile glasses with a brittle-to-ductile (BTD) transition at Poisson's ratio around 0.32. Most organic and metallic glasses possess Poisson's ratio above 0.32, and thus, feature fracture energy that is around three orders of magnitude higher than that of oxide glasses, which feature Poisson's ratio typically below 0.30. However, whether the BTD transition can also be observed in oxide glasses remains unknown due to the lack of fracture energy measurements on oxide glasses with high Poisson's ratio. In this work, we measure the fracture energy of six oxide glasses with high Poisson's ratio between 0.30 and 0.34. We find no clear relationship between the two parameters even in those that possess the same Poisson's ratio as ductile metallic glasses. This suggests that Poisson's ratio is not the main property to enhance the fracture energy of oxide glasses. To this end, we instead find a positive relation between fracture energy and Young's modulus of oxide glasses, and even for some metallic glasses, which could explain their absence of ductility. [ABSTRACT FROM AUTHOR]

In previous studies, the influence of flaws on macro-scale and nano-scale metallic glasses (MGs) has always been a topic of great interest, with important applications in engineering. Moreover, through experiments and simulations, many researchers draw contradictory conclusions of the notch sensitivity, including the notch strengthening, weakening, and insensitivity in different MGs. In order to better understand its atomic mechanism, classical molecular dynamics simulations have been performed on the nano-scale notched MGs in the present work to investigate the deformation modes under the uniaxial tension. According to the results, after setting notches, the MG samples exhibit a significant change from the shear to necking failure, which indicates a notch strengthening phenomenon. At the same time, the evolution of atomic structures suggests that the introduction of notches will increase the degree of shear localization and further disturb the structural order of MGs. The atomic displacement, which is different from shear strain, can also be used as an index to visually describe the deformation behavior of MGs and shows the high notch sensitivity. [ABSTRACT FROM AUTHOR]

Dynamic shear-modulus data are presented for two silicone oils DC704 and DC705 for frequencies between 1 mHz and 10 kHz at temperatures covering more than five decades of relaxation-time variation. Data are fitted to the alpha part of a phenomenological model previously shown to describe well the dynamic shear modulus of squalane, which has a large beta process [Hecksher et al., J. Chem. Phys. 146, 154504 (2017)]. That model is characterized by additivity of the alpha and beta shear compliance and by a high-frequency decay of the alpha process in proportion to ω−1/2, where ω is the angular frequency. The fits of the alpha part of this model to the DC704 and DC705 data are compared to fits by a Havriliak–Negami type model, a Barlow–Erginsav–Lamb model, and a Cole–Davidson type model. At all temperatures, the best fit is obtained by the alpha part of the squalane model. This strengthens the conjecture that so-called t -relaxation, leading to high-frequency loss decays proportional to ω−1/2, is generic to the alpha relaxation of supercooled liquids [J. C. Dyre, Phys. Rev. E 74, 021502 (2006); Nielsen et al., J. Chem. Phys. 130, 154508 (2009); and Pabst et al., J. Phys. Chem. Lett. 12, 3685–3690 (2021)]. [ABSTRACT FROM AUTHOR]

We propose an alternative theory for the relaxation of density fluctuations in glass-forming fluids. We derive an equation of motion for the density correlation function that is local in time and is similar in spirit to the equation of motion for the average non-uniform density profile derived within the dynamic density functional theory. We identify the Franz–Parisi free energy functional as the non-equilibrium free energy for the evolution of the density correlation function. An appearance of a local minimum of this functional leads to a dynamic arrest. Thus, the ergodicity breaking transition predicted by our theory coincides with the dynamic transition of the static approach based on the same non-equilibrium free energy functional. [ABSTRACT FROM AUTHOR]