Xuanhui Qu

This study presents a systematic comparative investigation of the soft magnetic properties, mechanical performance, and structural relaxation characteristics of two Fe-based amorphous ribbons, Fe₈₀Si₉B₁₁ and Fe₈₀Co₃Si₃B₁₀P₁C₃, subjected to heat treatment. Differential scanning calorimetry, X-ray diffraction, coercivity measurements, plate-bending evaluation, tensile tests, microhardness testing, and dynamic mechanical analysis are employed to elucidate the effect of elemental composition on thermal stability, brittle-to-ductile transition behavior, and relaxation kinetics of these amorphous systems. The results show that the β-relaxation peak in Fe₈₀Si₉B₁₁ is completely merged into the primary α-relaxation peak, whereas Fe₈₀Co₃Si₃B₁₀P₁C₃ exhibits a distinct β-relaxation peak at approximately 215 °C. The pronounced β-relaxation behavior of Fe₈₀Co₃Si₃B₁₀P₁C₃ contributes to superior bending toughness following heat treatment. In contrast, the weak β-relaxation response of Fe80Si9B11 results in a greater susceptibility to embrittlement. Furthermore, it is demonstrated that the evolution of microhardness can partially reflect the β-relaxation characteristics in amorphous ribbons.

In this study, a series of (Fe1-xCox)79Mo10B10Cu1 (x=0, 0.1, 0.2, 0.25, 0.3, 0.4, 0.5, 0.75, and 1) alloys are prepared by melt-spinning. All the alloys are amorphous as confirmed by both XRD and TEM. Thermal and magnetic properties are characterized by DSC, VSM and Mössbauer spectroscopy. Co addition reduces crystallization temperatures as well as their activation energies, but remains a wide temperature window of ~150 ℃ for nanocrystallization. A proper amount of Co element can enhance saturation magnetization, Curie temperature of amorphous phase and magnetic hyperfine field. Mössbauer analyses validate compositional heterogeneity locally with Mo-enriched and Co-enriched regions in these alloys. The (Fe0.6Co0.4)79Mo10B10Cu1 amorphous alloy, having a high saturation magnetization of 112 A·m2/kg, a small coercivity of 24 A/m, a high Curie temperature of ~400 °C and a large average hyperfine field nearly 30 T, has potential for high temperature application as soft magnet.

W-5Re, W-10Re, W-15Re, W-20Re and W-25.6Re alloys were fabricated via powder metallurgy, followed by rotary swaging and annealing at 1100 °C. The effects of Re content on relative density, microhardness, tensile properties at both ambient and elevated temperatures, microstructure and phase constitution were systematically investigated. The results show that all alloys exhibit relative densities exceeding 98.5%, indicating excellent densification. With the increase of rhenium (Re) content, the microhardness, room-temperature tensile strength and tensile strength at 1000 °C of the alloys all increase monotonically, reaching the maximum values of 581 HV, 1786.7 MPa and 1102.3 MPa for W-25.6Re alloy, respectively. In contrast, the tensile strength at 1600 °C decreases significantly and exhibits a trend of increasing first and then decreasing with rising Re content, with the peak value of 238.3 MPa obtained in W-15Re alloy.The room-temperature ductility first increases and then decreases, with the W-20Re alloy achieving the optimum elongation of 7.0%. X-ray diffraction (XRD) analysis reveals that the substitutional solid solution of Re atoms shifts the α-W diffraction peaks to higher angles, corresponding to lattice contraction. Electron backscatter diffraction (EBSD) results indicate that as Re content increases, the grain size first coarsens slightly and then refines, the proportion of low-angle grain boundaries gradually increases, and the residual internal stress first decreases and then increases. The synergistic effect of solid-solution strengthening and grain-boundary pinning is identified as the key mechanism governing the microstructure and mechanical properties of W-Re alloys.

This study presents a systematic comparative investigation of the soft magnetic properties, mechanical performance, and structural relaxation characteristics of two Fe-based amorphous ribbons, Fe₈₀Si₉B₁₁ and Fe₈₀Co₃Si₃B₁₀P₁C₃, subjected to heat treatment. Differential scanning calorimetry, X-ray diffraction, coercivity measurements, plate-bending evaluation, tensile tests, microhardness testing, and dynamic mechanical analysis are employed to elucidate the effect of elemental composition on thermal stability, brittle-to-ductile transition behavior, and relaxation kinetics of these amorphous systems. The results show that the β-relaxation peak in Fe₈₀Si₉B₁₁ is completely merged into the primary α-relaxation peak, whereas Fe₈₀Co₃Si₃B₁₀P₁C₃ exhibits a distinct β-relaxation peak at approximately 215 °C. The pronounced β-relaxation behavior of Fe₈₀Co₃Si₃B₁₀P₁C₃ contributes to superior bending toughness following heat treatment. In contrast, the weak β-relaxation response of Fe80Si9B11 results in a greater susceptibility to embrittlement. Furthermore, it is demonstrated that the evolution of microhardness can partially reflect the β-relaxation characteristics in amorphous ribbons.

Following publication, it has been confirmed that authors cited one reference [46] that has been retracted prior to the publishing of this paper

Lithium metal anodes are regarded as a key negative electrode material for next-generation batteries due to the high specific capacity. However, their practical application is hindered by significant volume fluctuations and uncontrolled lithium dendrite growth. Herein, a nitrogen-doped three-dimensional porous carbon framework embedded with cobalt nanoparticles (Co@NCF) was synthesized via a one-step foaming method. The three-dimensional porous carbon framework with high specific surface area reduces the local current density and provides ample pore structure, effectively inhibiting the Li dendrite formation and mitigating the volume expansion. Furthermore, the suppression of dendrite growth and volume changes interrupts the vicious cycle involving repeated fracture and reformation of the solid electrolyte interphase (SEI), along with the continuous consumption of active lithium and electrolyte. Notably, the uniformly dispersed cobalt nanoparticles serve as favorable nucleation sites for lithium metal deposition, while the nitrogen doping enhances the lithiophilicity of the carbon framework. By virtue of those, the Li@Co@NCF anode exhibits superior cycling stability (900h) and high coulombic efficiency (~98%) at 1 mA cm-2 for 1 mAh cm-2 Li plating/stripping. In a full cell of Li@Co@NCF//NCM811, the decent reversible capacity (129.0 mAh·g-1) and capacity retention rate (84.3%) are delivered after 300 cycles at a current density of 1C. It provides a viable strategy for developing safe and long-life lithium metal anodes.