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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.

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.

Zr-based amorphous alloys are innovative materials with promising applications, such as biological sectors and sports facilities. This study evaluates the effects of magnetic field assistance on electrolyte jet machining (EJM) of these alloys in alcohol-based electrolyte. Firstly, the electrochemical-induced interface structural evolution at different regions is examined to elucidate the dissolution mechanism of Zr-based amorphous alloys in the NaCl ethylene glycol electrolyte via atomic structural analysis. Then, based on the Cl¯ diffusion coefficients in the diffusion region and convection region of the inter-electrode gap calculated from the molecular dynamics (MD) simulation, the magnetic field is found to increase the total diffusion coefficient of Cl¯ in the diffusion and convection regions, improving the uniformity of the electrolyte and surface smoothness. Compared with a magnetic field parallel to the electric field, a perpendicular magnetic field has more improvement in machining performance. Furthermore, combined perpendicular and parallel magnetic fields of 0.1 T increase cavity depth by 47.91%, the MRR by 30.88%, and reduced surface roughness Ra from 0.364 to 0.298 μm, compared with the case without the magnetic field assistance. This research underscores the efficacy of magnetic field assistance in advancing the precision and sustainability of EJM for Zr-based amorphous alloys.

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.

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.

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.

Amorphous alloy is an emerging metal material, and its unique atomic arrangement brings it the excellent properties of high strength and high hardness, and, therefore, have attracted extensive attention in the fields of electronic information and cutting-edge products. Their applications involve machining and forming, make the machining performance of amorphous alloys being a research hotspot. However, the present research on amorphous alloys and their machining performance is widely focused, especially for Fe-based amorphous alloys, and there lacks a systematic review. Therefore, in the present research, based on the properties of amorphous alloys and Fe-based amorphous alloys, the fundamental reason and improvement method of the difficult-to-machine properties of Fe-based amorphous alloys are reviewed and analyzed. Firstly, the properties of amorphous alloys are summarized, and it is found that crystallization and high temperature in machining are the main reasons for difficult-to-machine properties. Then, the unique properties, preparation and application of Fe-based amorphous alloys are reviewed. The review found that the machining of Fe-based amorphous alloys is also deteriorated by extremely high hardness and chemical tool wear. Tool-assisted machining, low-temperature lubrication assisted machining, and magnetic field-assisted machining can effectively improve the machining performance of Fe-based amorphous alloys. The combination of assisted machining methods is the development trend in machining Fe-based amorphous alloys, and even amorphous alloys in the future. The present research provides a systematic summary for the machining of Fe-based amorphous alloys, which would serve as a reference for relevant research.

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.