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The Cu₄₃Zr₄₃Ag₇Al₇ alloy was obtained in an amorphous form through inert gas spray forming, followed by separation using a tower cyclone gas separator. The resulting spherical particles were about 11 μm in size. The consolidation of the powder was carried out using two distinct methods. First, Spark Plasma Sintering (SPS) was performed under a pressure of 35 MPa at two temperatures: 750°C and 900°C. Second, the High-Pressure High-Temperature (HPHT) method was applied, utilizing a toroidal-type Bridgman apparatus at about 560°C under a pressure of 7.8 GPa. In both processes, the consolidation duration was one minute. Differential scanning calorimetry (DSC), X-ray diffraction (XRD), and high-resolution transmission electron microscopy (HRTEM) analyses revealed distinct differences in the crystallization behavior of the alloy. SPS processing led to complete crystallization, resulting in the formation of Zr₂Cu, Ag₂Al, and Cu₁₀Zr₇ crystalline phases. In contrast, the HPHT method significantly delayed crystallization, with only nanocrystalline nuclei observed within the amorphous matrix. Additionally, the application of high pressure in the HPHT process resulted in lower porosity and higher hardness compared to the SPS method.

Phenol, an essential feedstock widely used in manufacturing and chemical industries, inevitably results in the discharge of phenol-laden wastewater. To enhance the phenol-degradation efficiency of Fe-based amorphous alloys, a novel atomic-scale fabrication approach for Fe-Cu galvanic couples is proposed, enabling the rapid and uniform formation of micro/nano Fe-Cu structures on the surface of Fe-based alloys with significant improvement in the catalytic activity towards phenol. Micron/nano Fe-Cu couples can be fabricated within 15 s at 45 °C. Phenol degradation experiments reveal that the pristine amorphous alloy exhibits a 40 min hatching period before the phenol removal process, and it exhibits a kinetic constant (kobs) of 0.1596 min−1 after the hatching period, under conditions of 50 °C, 0.5 g/L catalytic loading, 10 mmol/L H2O2, and pH = 3 towards a 50 mg/L phenol solution. With the micro/nano Fe-Cu galvanic couples, the kobs value markedly increased to 2.23~2.36 min−1 under identical conditions except for 3 mmol/L H2O2, corresponding to approximately a 14-fold improvement. This cost-effective and time-efficient atomic-scale fabrication strategy offers a promising platform for the development of next-generation catalytic alloys and functional materials.

Developing new soft magnetic amorphous alloys with a low cost and high saturation magnetization (Bs) in a simple alloy system has attracted substantial attention for industrialization and commercialization. Herein, the glass-forming ability (GFA), thermodynamic properties, soft magnetic properties, and atomic structures of Fe80+xSi5−xB15 (x = 0–4) amorphous soft magnetic alloys were investigated by ab initio molecular dynamics (AIMD) simulations and experiments. The pair distribution function (PDF), Voronoi polyhedron (VP), coordination number (CN), and chemical short- range order (CSRO) were analyzed based on the AIMD simulations for elucidating the correlations between the atomic structures with the glass-forming ability and magnetic properties. For the studied compositions, the Fe82Si3B15 amorphous alloy was found to exhibit the strongest solute–solute avoidance effect, the longest Fe-Fe bond, a relatively high partial CN for the Fe-Fe pair, and the most pronounced tendency to form more stable clusters. The simulation results indicated that Fe82Si3B15 was the optimum composition balancing the saturation magnetization and the GFA. This prediction was confirmed by experimental observations. The presented work provides a reference for synthesizing new Fe-Si-B magnetic amorphous alloys.

Transverse thermoelectric generation using magnetic materials is essential to develop active thermal engineering technologies, for which the improvements of not only the thermoelectric output but also applicability and versatility are required. In this study, using combinatorial material science and lock-in thermography technique, we have systematically investigated the transverse thermoelectric performance of Sm-Co-based alloy films. The high-throughput material investigation revealed the best Sm-Co-based alloys with the large anomalous Nernst effect (ANE) as well as the anomalous Ettingshausen effect (AEE). In addition to ANE/AEE, we discovered unique and superior material properties in these alloys: the amorphous structure, low thermal conductivity, and large in-plane coercivity and remanent magnetization. These properties make it advantageous over conventional materials to realize heat flux sensing applications based on ANE, as our Sm-Co-based films can generate thermoelectric output without an external magnetic field. Importantly, the amorphous nature enables the fabrication of these films on various substrates including flexible sheets, making the large-scale and low-cost manufacturing easier. Our demonstration will provide a pathway to develop flexible transverse thermoelectric devices for smart thermal management.

When metals are modified by second-phase particles or fibers, metal matrix composites (MMCs) are formed. In general, for a given metallic matrix, reinforcements differing in their chemical nature and particle size/morphology can be suitable while providing different levels of strengthening. This article focuses on MMCs reinforced with metallic glasses and amorphous alloys, which are considered as alternatives to ceramic reinforcements. Early works on metallic glass (amorphous alloy)-reinforced MMCs were conducted in 1982–2005. In the following years, a large number of composites have been obtained and tested. Metallic glass (amorphous alloy)-reinforced MMCs have been obtained with matrices of Al and its alloys, Mg and its alloys, Ti alloys, W, Cu and its alloys, Ni, and Fe. Research has been extended to new compositions, new design approaches and fabrication methods, the chemical interaction of the metallic glass with the metal matrix, the influence of the reaction products on the properties of the composites, strengthening mechanisms, and the functional properties of the composites. These aspects are covered in the present review. Problems to be tackled in future research on metallic glass (amorphous alloy)-reinforced MMCs are also identified.

The new type of Fe 83 − x Si 2.5 B 12 P 2.5 C x (x = 0, 0.5, 1.0, 1.5, 2.0 at%) amorphous soft magnetic system with low cost, high saturation magnetization and low coercivity were designed and prepared by means of rapid quenching. The effect of C on the amorphous formability, thermal stability, and soft magnetic properties in the alloy system were studied. Results suggest that the addition of small atom C can promote the formation of densely atomic structure of alloy, thereby promoted the enhancement of amorphous formability. With the increase of C content, the temperature interval between two crystallization peaks increases first and then decreases. When C content is 1.0 at%, Δ T ( T x2 - T x1 ) reaches the maximum value, of about 109.9 ℃, which is beneficial to enhance the thermal stability and soft magnetic properties. As the concentration of C is raised, the B s exhibit a pattern of increases followed by a subsequent decrease, while coercivity changes in the opposite way. When the C content is 1.0 at%, the B s of the alloy reaches the highest value of 1.78 T and the coercivity exhibits the best which is 14.055 A/m. The results offer important contributions to the design and advancement of high B s amorphous soft magnetic materials for industrial applications involving amorphous electric motors.

Zr48Cu47.5Al4Co0.5 bulk amorphous alloy composites were prepared by selective laser melting (SLM) technology under different processing conditions and their non-isothermal crystallization behaviors were systematically investigated. The results show that the crystallization phases are Cu10Zr7 and CuZr2 for both gas-atomized powder and SLMed samples. The dependence of volume fraction of Cu10Zr7 and CuZr2 on laser energy density can be fitted by an exponential function. The crystalline sizes of Cu10Zr7 and CuZr2 linearly increase with increasing energy density. The thermal stability is larger for the gas-atomized powders than for the SLMed bulk samples. It is interestingly found that there is an exponential relationship between the crystallization enthalpy ΔHx and the amorphous content. In addition, the glass transition is more difficult for the gas-atomized powders than for the SLMed bulk samples. The crystallization procedure is more difficult for the SLMed bulk samples than for the gas-atomized powders. The local activation energy Eα decreases with increasing α for the gas-atomized powder and the SLMed bulk samples. In addition, the Eα is larger for the SLMed bulk samples than for the gas-atomized powder at the corresponding crystallization fraction α. The dependence of the local Avrami exponent n(α) on the α is similar for both the gas-atomized powders and the SLMed bulk samples at studied heating rates. The crystallization mechanism is also discussed.

This study compares the effects of adding Mo, Cu, and Sn elements on the decolorization performance of Fe77Si13B9M1 (M = Mo, Cu, or Sn) amorphous alloys. After the addition of Cu and Sn elements, the Fe-Si-B amorphous alloys generate three-dimensional (3D) petal-like nanostructured corrosion products during the decolorization process. These petal-like nanostructures possess a high specific surface area and excellent adsorption capacity, thereby effectively promoting the decolorization of dyes. Furthermore, the influence of Fe content variation on the decolorization performance of Fe77+xSi13−xB9Cu1 (x = 0, 2, or 4) and Fe77+xSi13−xB9Sn1 (x = 0, 2, or 4) alloys was investigated. The glass-forming ability of Fe77+xSi13−xB9Cu1 alloys decreases with increasing Fe content, leading to the precipitation of α-Fe crystalline phases starting from Fe79Si11B9Cu1. As the crystallinity increases, the decolorization performance of the alloys gradually deteriorates. In contrast, the Fe77+xSi13−xB9Sn1 alloys maintain their amorphous structure even with increasing Fe content, and their decolorization performance for Orange II improves accordingly. The high decolorization efficiency of FeSiBSn amorphous alloys for Orange II can be attributed to their unique self-refreshing properties.

The high hardness performance of Fe-based amorphous alloys give them unique advantages in the field of wear-resistant materials, while the performance degradation after crystallization limits their application range. In this study, rod-shaped bulk Fe 41 amorphous alloy was prepared, and its crystallization characteristics were studied in response to its high temperature conditions in wear service environment. Aging treatments were carried out on the materials at different temperatures, and the characteristics and mechanism of amorphous alloy crystallization transformation were analyzed. The research results indicate that the crystallization rate of Fe 41 bulk amorphous alloy exhibits a bilinear characteristic with increasing temperature, and the transformation temperature at which crystallization significantly accelerates is between 180 °C and 250 °C. The main reason for the surface crystallization of Fe 41 bulk amorphous alloy is the local stress release caused by the detachment of the second phase under aging temperature conditions. For the interior of the material, structural constraints effectively suppress crystallization transformation within 350 °C.

High entropy amorphous alloys (HEAAs) are materials that have received much attention in recent years. They exhibit many unique properties; however, research on their composition design method has not been deep enough. In this paper, we summarized some effective composition design strategies for HEAAs. By adjusting the atomic ratio from quinary bulk metallic glasses, Ti20Zr20Cu20Ni20Be20 HEAA with a high fracture strength of 2315 MPa was designed. By similar element addition/substitution, a series of Ti–(Zr, Hf, Nb)–Cu–Ni–Be HEAAs was developed. They possess good glass-forming ability with a maximum critical diameter of 30 mm. Combining elements from those ternary/quaternary bulk metallic glasses has also proved to be an effective method for designing new HEAAs. The effect of high entropy on the property of the alloy, possible composition design methods, and potential applications were also discussed. This paper may provide helpful inspiration for future development of HEAAs.