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To provide insight into the effect of deformation microstructure on the precipitation behavior, an Al-4Mg-0.3Cu alloy was processed by high-pressure torsion followed by subsequent in-situ heating in a transmission electron microscope. Structural characterization revealed significant differences in the size, composition and spatial distribution of the precipitates in the alloy subjected to different strains. Different grain sizes led to various dislocation substructures and grain boundary volume fractions, which in turn governed precipitation behaviors. In addition, the composition of the precipitates along the grain boundaries varied with the grain size due to the change of the grain boundary volume fraction and diffusion behavior. [ABSTRACT FROM AUTHOR]

With the tremendous demand for high energy and power operation in energy storage devices, supercapacitors (SCs) have demonstrated to be one of the most viable devices for electrical energy conversion and storage applications due to their superior capacity than conventional capacitors and higher power density than batteries. However, the insufficient capacitance of the anode materials severely impedes the development of SCs. Due to their astonishing theoretical capacitance, nickel sulfides have aroused immense attention for the next generation of supercapacitors. But its inability to satisfy the anticipated capacitance values and insufficient structural durability severely hinder the application of capacitive energy storage. Herein, doping vanadium into nickel sulfide (V-Ni 3 S 2 , denoted as VNS) was grown on the surface of nickel foam by a one-step hydrothermal method using nickel foam as a nickel source. The results showed that Ni 3 S 2 doped uniformly with valence-rich vanadium remarkably enhanced the redox reaction. Integrating two-dimensional nanosheets into three-dimensional nanoflower morphology not only expands the number of active sites but also enhances the stability of the structure. The VNS electrode with clearly defined ion diffusion channels and affluent redox activity centers significantly enhances the reversible capacitance and the stabilized longevity (2072 F g−1 at 1 A g−1, capacitance retention of 86.4% after 10,000 cycles). Furthermore, using the VNS and activated carbon as cathode and anode electrodes, respectively, the fabricated hybrid supercapacitor delivers an excellent energy density of 81.33 Wh kg−1 at a power density of 160 W kg−1 and agelong cycling durability (capacitance retention of 82.2% after 10,000 cycles). These strategies enlighten the electrochemical properties of various metal sulfide materials employed in energy storage devices. [Display omitted] • The highest specific capacitance of 2072 F g−1 at 1 A g−1 achieved for valence-rich vanadium is doped into Ni 3 S 2. • Integrating two-dimensional nanosheets into three-dimensional nanoflower morphology can expand the number of active sites. • The structural durability of nickel sulfide is improved with capacitance retention of 86.4% over 10,000 cycles. • The assembled hybrid supercapacitor exhibits outstanding electrochemical performances. [ABSTRACT FROM AUTHOR]

Highlights: [•] Fe80−xNi x P13C7 (x =0–30at.%) BMGs were prepared by fluxing and J-quenching techniques. [•] The small amount of substitution of Ni for Fe can enhance the glass forming ability. [•] The substitution of Ni for Fe can greatly enhance the plastic strain of FeNiPC BMGs. [•] Fe60Ni20P13C7 BMG has a εP of >10% which is the largest one reported for Fe-based BMGs. [Copyright &y& Elsevier]

Abstract: Bulk magnetic Fe80− x Mo x P13C7 (x =0, 3, 6, 9 and 12at.%) glassy alloys were successfully prepared by the fluxing technique and J-quenching technique. The effect of Mo substitution for Fe on the glass formation ability (GFA), thermal stability, mechanical properties and magnetic properties has been studied systematically. It was found that the substitution of a small amount of Mo for Fe can dramatically enhance the GFA, which in turn, the critical maximum diameter for fully glass formation reached to 5.5mm for x =3 and 6.0mm for x =6, respectively. However, excessive substitution will promote the formation of Fe2Mo3 competition crystalline phase leading to the degradation of the GFA. Furthermore, the substitution of proper content of Mo for Fe can obviously enhance the mechanical properties of the present Fe-based alloys, which can be identified that the current FeMoPC bulk metallic glass possesses a high fracture strength (over 3000MPa) as well as a large room temperature plasticity (above 5%). In addition, the Mo doping FePC bulk metallic glasses exhibit good soft magnetic properties with a relatively high saturation magnetization of over 1.0T at room temperature. [Copyright &y& Elsevier]

The ferrimagnetic nodal-line semiconductor Mn 3 Si 2 Te 6 , featuring a quasi-two-dimensional crystal structure, has attracted significant attention owing to its rich physical properties. Here, we systematically investigate the magnetic properties of its isostructural compound, Mn 3 Si 2 Se 6. The magnetism of this material is attributed to the Mn atoms, which exhibit antiferromagnetic interactions among the Mn atoms. The competition between antiferromagnetic exchange interactions results in an overall ferrimagnetic state, with a second-order transition from paramagnetic to ferrimagnetic occurring at 68 K. Critical exponents are derived using various common experimental techniques, including the modified Arrott plot, Kouvel-Fisher method, and critical isotherm analysis. The results indicate that the magnetism of Mn 3 Si 2 Se 6 closely aligns with the mean-field model, with critical exponents β , γ , and δ determined as 0.475(3), 1.059(3), and 3.20(1), respectively, at the critical temperature of 68.3(2) K. Moreover, the curves of the magnetic entropy change − Δ S M (T , H) exhibit a peak around T c , with − Δ S M max amounts to 4.61 (3.63) J kg−1 K−1 for H ∕∕ ab (∕∕ c) with a field change of 7 T. The estimated magnetic entropy value near T c through specific heat is remarkably saller than the expected spin entropy of Mn2+ ions, indicating the presence of short-range interactions in the paramagnetic region. • The competition exchange interactions result in an overall ferrimagnetic state in Mn 3 Si 2 Se 6. • Magnetism of Mn 3 Si 2 Se 6 aligns with the mean-field model. • Specific heat analysis reveals short-range interactions in Mn 3 Si 2 Se 6 's paramagnetic region. [ABSTRACT FROM AUTHOR]

Abstract: Monoclinic bismuth vanadate (m-BiVO4) micro-/nanostructures with different sizes and morphologies were successfully prepared via a facile and rapid microwave and ultrasonic wave combined technique. The obtained BiVO4 products were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and UV–vis diffuse reflection spectroscopy (DRS). It was found that the solvent and pH value had a significant influence on morphology, size and crystalline structure of the product. Nut-like, potato-like and broccoli-like monoclinic BiVO4 were fabricated in different solvents. The crystal phase could be modulated by varying the pH value of reaction system. The photocatalytic activities of the products were also evaluated by the degradation of Rhodamine B (RhB) under visible light irradiation. The result revealed that the photocatalytic activities of BiVO4 nanostructures were closely related to the crystalline phase, band gap and particle size. Monoclinic BiVO4 nanoparticles with small crystal size and large band gap exhibited remarkable photocatalytic performance. [Copyright &y& Elsevier]

Abstract Recently, high-entropy alloys (HEAs) reinforced with ceramic particles have attracted increasing attentions due to their excellent hardness, strength and wear resistance. In this study, AlCoCrFeNi-xNbC high-entropy alloy (HEA) coatings (x = 10, 20, 30 wt%) were prepared by laser cladding. The phase constituents, microstructure and mechanical properties of the HEAs were investigated using X-ray diffraction (XRD), scanning electron microscopy (SEM), electron back-scatter diffraction (EBSD), transmission electron microscope (TEM), microhardness and wear resistance tests. Due to the high entropy effect, the AlCoCrFeNi HEAs composites comprise only simple BCC and FCC structure phases. The addition of NbC particles results in a decrease in the fraction of the FCC phase. NbC particles are mainly distributed at the grain boundary in the HEAs with the addition of NbC. NbC particles have an advantage on the inhibition of HEA grain growth due to a strong pinning effect. The microhardness and the wear resistance of HEA composite improved significantly with the addition of NbC particles. A good comprehensive mechanical properties was obtained at the HEA with the addition of 20 wt% NbC particles. For the 20 wt% NbC-adding HEA, the average Vickers hardness is 525 HV, the average friction coefficient value is 1.023 and the mass loss is 1.05 mg. Highlights • AlCoCrFeNi-xNbC high-entropy alloys are prepared and researched. • The addition of NbC particles restrains the formation of FCC phase. • The addition of NbC particles plays a role of grain refinement. • The addition of NbC particles increases the mechanical properties of the alloys. [ABSTRACT FROM AUTHOR]

In this study, AlCrFeNiMn x high-entropy alloy coatings (x = 0, 0.5, and 1) were successfully prepared on a copper substrate by laser cladding. The influence of Mn addition was investigated on the phase constituent, microstructure, and mechanical properties of the HEA coatings. Due to the high-entropy effect, the AlCrFeNiMn x HEA coatings comprised only simple BCC and FCC structure phases. Moreover, the addition of Mn elements inhibited the formation of FCC phases due to the variation of ΔG mix , ΔH mix , δ, ∆x and VEC value. The addition of Mn leads to solute effect, so the grains were significantly refined with an increase in Mn content. When the Mn content was 0.5, good comprehensive mechanical properties were obtained with an average Vickers hardness of 625 HV, average friction coefficient value of 0.42, and a mass loss of 1.02 mg. • AlCrFeNiMn x HEA coatings are prepared on a copper substrate by laser cladding. • The addition of Mn inhibited the formation of FCC phase of the AlCrFeNiMn x HEAs. • The addition of Mn can significantly refine grains of the AlCrFeNiMn x HEAs. • The addition of Mn can improve the mechanical properties of the AlCrFeNiMn x HEAs. [ABSTRACT FROM AUTHOR]

In this study, Al-Cu alloy suitable for laser powder bed fusion (LPBF) is rapidly developed through casting and laser remelting. The microstructure of as-cast Al-Cu alloy is consisted of equiaxed grains, and it was significantly refined after remelting. The Vickers hardness in the remelted zone improved by approximately 33.7% compared with that of as-cast Al-Cu alloy. The effects of different element content on Al-Cu-Mg-Zr alloy were analyzed, and optimum alloy composition was obtained with Al-5Cu-2Mg-1Zr-0.3Mn-0.15Ti through comparing microstructure, the hardness and other properties after remelting. The nano-indentation hardness and Young's modulus of remelted Al-5Cu-2Mg-1Zr-0.3Mn-0.15Ti alloys were 1.86 and 86.7 GPa, respectively. The microstructure was dense without obvious crack after LPBF forming, and the tensile strength, yield strength and elongation values reach 483 MPa, 365 MPa and 13.4% after solution treatment. • The suitability of LPBF-fabricated alloys composition was judged by cast and laser remelting.. • The ultra-fine microstructure and Al2Cu dispersion distribution were observed in laser remelting alloy. • New composition Al-Cu alloy prepared by LPBF shows a dense structure and good mechanical behavior. [ABSTRACT FROM AUTHOR]

• Seven AlSi10Mg alloys with different construction angles were prepared and researched. • The grains in vertical planes change from columnar grains to irregularly arranged grains, and then to equiaxed grains. • The AlSi10Mg exhibites mechanical property anisotropy that is a result of grain structure, dispersed Si, and residual stress. In this study, seven AlSi10Mg bulks with different construction angles (0°, 15°, 30°, 45°, 60°, 75°, and 90°) were fabricated by selective laser melting (SLM). The effects of different construction angles on the microstructure and mechanical properties of AlSi10Mg alloys were investigated. Increasing the construction angle changed the laser track segments from an ellipse to a semi-ellipse and then to fish-scale, specifically again from a semi-ellipse to an ellipse, due to the decrease of the laser radiation area. Meanwhile, the grains in the vertical planes changed from columnar grains to irregularly arranged grains, and then to equiaxed grains. The 45° sample exhibited the highest hardness of 154.44 HV 0.1. The 60° sample had a good combination of strength and plasticity with a tensile strength of 463.54 MPa, yield strength of 283.37 MPa, and elongation of 9.25%. The observed mechanical property anisotropy of the current AlSi10Mg alloy was a result of the pores, equiaxed grain structure, ultra-fine equiaxed sub-grains, and working hardening. In addition, the difference in the sample microstructures was attributed to the construction angles and deposited layer area. [ABSTRACT FROM AUTHOR]

A Ni-coated graphene (Ni-Gr) reinforced Inconel 625 composite was prepared by selective laser melting. The microstructure of the composite exhibited random aligned columnar dendrites due to the addition of Ni-Gr. The Ni-Gr defects were alleviated under high-intensity laser-beam irradiation. The Micro-CT showed that the pore density increased by 46% of Inconel 625 due to the addition of Ni-Gr. The flaky, open-ring Ni-Gr appeared due to the action of Marangoni convection and the surface tension. Furthermore, the addition of Ni-Gr improved the diffusion capacity of the friction heat. Inconel 625 composite displayed tiny bits of oxidized debris. [ABSTRACT FROM AUTHOR]

The transport, magnetic and thermodynamic properties of the cerium oxide bismuth compound Ce 2 O 2 Bi are systematically investigated in a wide temperature regime. The compound crystallizes in the anti-ThCr 2 Si 2 -type structure consisting of a separated Bi2− square net layer between the CeO layers. In the high temperature regime 200–300 K, the compound shows the conventional metallic behavior and localized 4 f electrons of Ce3+ ions. In the low temperature regime 15–30 K, the resistivity increases with a logarithmic temperature dependence, accompanied with the negative magnetoresistance and a low carrier density. Further decreasing temperature, the resistivity drops rapidly below 6.2 K, signaling an antiferromagnetic ordering transition within the Kondo phase. Both susceptibility and specific heat display a similar transition around the same temperature, accompanied with a reduced magnetic entropy. A large Sommerfeld coefficient ∼ 336 mJ/mol K2 is obtained by fitting the specific heat data and no superconductivity is observed down to 0.3 K. All these observations suggest that Ce 2 O 2 Bi is a rare low carrier density Kondo lattice compound whose interlayer hybridization between 4 f electrons of Ce3+ ions and conduction 6 p electrons of Bi2− ions plays a crucial role. • Ce 2 O 2 Bi with the anti-ThCr 2 Si 2 -type structure is characterized as an antiferromagentic Kondo lattice compound with a low carrier density. • A rare example of Kondo lattices with a Bi2- square net layer between the CeO layers. • It becomes Kondo coherent below 10.7 K and antiferromagentically orders at T N = 6.2 K. • The Sommerfeld coefficient of Ce 2 O 2 Bi is as large as 336 mJ/mol K 2 , indicating an enhanced hybridization between Ce-4 f electrons and conduction electrons."Use bullets instead of numerals for numbering. [ABSTRACT FROM AUTHOR]