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In this paper, tin-phosphate amorphous glass and nano-crystallized ceramic materials were synthesized by sol-gel methods and heat treated at 400 °C with the composition of x SnO 2 − (100- x)P 2 O 5 (x SnP: ' x ' from 40 to 90 mol%). The electrical and thermal properties of tin-phosphate materials were investigated by electrical impedance spectroscopy (EIS) and thermogravimetry – differential thermal analysis – mass spectroscopy (TG–DTA–MS). Moreover, the local structure of x SnP was characterized by 119Sn-Mössbauer and magic angle spinning (MAS) 31P NMR spectroscopies. Homogeneous glasses were obtained for x SnP with ' x ' from 50 to 80, while Sn(HPO 4), SnO 2 , and Sn 3 (PO 4) 2 nanoparticles formed in 40SnP and 90SnP compositions, respectively. The nano-crystallized 40SnP and 90SnP samples showed large electrical conductivity (σ) of 2.02×10−5 and 1.04×10−4 S cm−1 due to the conductive crystalline phases of SnP 2 O 7 and defective SnO 2 , respectively. The lower σ of about 10−8 S cm−1 were recorded for x SnP with ' x ' from 50 to 80 owing to the decomposition of the 3D network built by phosphate tetrahedrons. 119Sn-Mössbauer spectra proved the growing number of SnIVO 6 units, which do not contribute to the rise of electrical conductivity. On the other hand, larger σ values of 1.79×10−4 and 6.4×10−3 S cm−1 were confirmed for 40SnP and 90SnP samples after heat treatment, resulting in partial reduction of SnIV to SnII and growing of the 3D network structure by PO 4 3−. It is concluded that highly electrically conductive x SnP samples can be synthesized by the sol-gel method followed by slow heat treatment. In addition, the battery evaluation was performed of x SnP samples as cathode and anode in a sodium-ion battery. The highest initial capacity recorded for 90SnP nano-crystallized ceramic at 37.97 mAh g−1 under a current rate of 20 mA g−1 with capacity retention (%) of 48.15% after 100 cycles as a cathode material. The anode test showed that the 40SnP nano-crystallized ceramic has the largest initial capacity of 375 mAh g−1 and after heat treatment 50SnP glass significantly increased to 425 mAh g−1 compared with 186 mAh g−1 before heat treatment. Also, the heat treatment effect on the initial capacity of 90SnP nano-crystallized ceramic with observation largest value of 470 mAh g−1. These results open the way to maybe applying these glass and nano-crystallized ceramic materials in all-solid-state batteries. • The x SnO 2 −(90− x)P 2 O 5 glass was successfully prepared with a wider chemical composition of SnO 2 concentration from 50 to 80 mol% by the sol-gel method. • The 40SnP and 90SnP samples exhibited notably high σ 's of 1.79×10−4 and 6.40×10−3 Scm−1 attributed to their elevated levels of proton conductivity. • 90SnP as cathode demonstrated the highest initial capacity, achieving 37.97 mAh g−1 and maintaining a capacity retention of 48.15% after 100 cycles. • 40SnP and 90SnP exhibited a large initial capacity of 375 mAh g−1 and 470 mAh g−1, as anode materials in SIBs. [ABSTRACT FROM AUTHOR]

Heat treatment is necessary for GW63K (Mg-6Gd-3Y-0.5Zr, wt%) alloy fabricated by wire are additive manufacturing (WAAM) to improve the mechanical properties before final applications. Considering the unique solidification process and microstructure of WAAMed GW63K alloys, the heat treatment parameters must be different from the cast or forged ones. Thus, the present paper investigated the influence of solution temperature and time on the microstructure and mechanical properties of WAAMed GW63K, as well as the aging temperature and time. It was found that the as-deposited alloy exhibited fine equiaxed α-Mg grains with an average size of 13 μm and few eutectic phase Mg 24 (Gd, Y) 5 around the grains. The proper temperature of solution treatment was 480℃ and the proper time was 0.5 h, lower and shorter than cast ones. After solution treatment, the average size of α-Mg grains almost remained the same and nearly all of the eutectic phase dissolved. To exert precipitation strengthening to a larger extent, we conduct aging treatment at 175°C, 200°C, and 225°C and draw their age-hardening curves. Besides, a superior strength /ductility trade-off was obtained peak aging at 200°C for 80 h, with the ultimate tensile strength of 337±8 MPa, yielding strength of 231±2 MPa, and elongation of 8.9±1.0%. This outstanding strength can be accounted for by the refinement strengthening of fine microstructure inherited from as-deposited GW63K alloy and precipitation strengthening from dense β′ precipitates with a remarkable plate aspect ratio. Besides, suitable β′ precipitates could support a favorable work hardening effect and compatible deformation capability. • The Mg-6Gd-3Y-0.5Zr alloy with low rare earth content fabricated by WAAM has obtained fine microstructure. • The refinement of microstructure would be retained under an optimal solution treatment (480°C×0.5 h). • A superior strength /ductility trade-off with UTS of 337±8 MPa, YS of 231±2 MPa and EL of 8.9±2.0% was obtained. [ABSTRACT FROM AUTHOR]

In this paper, the best magnetic properties of FeSiBCr/wollastonite soft magnetic composites were explored by adjusting the content of wollastonite powder and annea- ling temperature. FeSiBCr/wollastonite soft magnetic composites with low loss and high quality factor were successfully prepared by adding micron-sized wollastonite po-wder into amorphous magnetic powder. Wollastonite was used as the insulating coating material of amorphous magnetic powder for the first time, which showed good performance in reducing the loss of magnetic powder. The loss change of FeSiBCr/wollastonite magnetic powder cores was studied by B-H analyzer and loss separation analysis model. The results show that the total loss (P cv) of FeSiBCr/woll- astonite composite cores is lower than that of the pure FeSiBCr cores. With the incre- ase of wollastonite powder content and annealing temperature, the total loss of FeSiBCr/wollastonite composite powder cores shows a trend of first decreasing and then increasing. The composite powder cores containing 0.8 wt% wollastonite powder was heat treated at 678 K for 1 hour under the protection of nitrogen, and its magnetic properties were the best, with a permeability of 28.93 and a loss of 196.2 mW/cm3(f =1 MHz and B m =20 mT). Wollastonite is a new coating material, which has a good effect of reducing loss. At the same time, this work also provides a new scheme for reducing the total loss of soft magnetic powder cores. • A novel FeSiBCr/wollastonite soft magnetic composite was successfully prepared. • The micron-sized wollastonite powder was first used in soft magnetic composites. • A simple scheme for reducing composite powder core is provided. • This work provides a new idea to reduce the loss by mixing two powders. [ABSTRACT FROM AUTHOR]

In this paper, heterogeneous L1 2 particles were successfully introduced into Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA by two-stage aging treatment. Compared with the homogeneous particles, the heterogeneous L1 2 particles strengthened alloy exhibits enhanced strength-plasticity synergy. The tensile elongation is 23.2%, which is higher than all samples with the homogeneous particles, and the yield strength remains at 942 MPa, which is equivalent to the micro particles (972 MPa) with the highest yield strength in the homogeneous particles. Further analysis of the strengthening and deformation mechanisms revealed that precipitation hardening, and heterogeneous deformation-induced hardening were the main factors for the enhanced strength. The deformation-induced layered fracture networks, high-density Lomo-Cottrell locks, and heterogeneous L1 2 particles microstructure characteristics significantly improve the strain hardening ability; GNDs accumulate at the heterogeneous interface to alleviate the stress concentration at the GBs and improve the tensile plasticity of the MPEA with heterogeneous L1 2 particle structure. The heterogeneous L1 2 particle structure obtained through two-stage aging treatment without severe mechanical deformation has attractive engineering application potential. These properties of Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA with heterogeneous L1 2 particle structure have important enlightening and practical value. • Designed and prepared Ni 38 Co 25 Fe 13 Cr 10 Al 7 Ti 7 MPEA with heterogeneous L1 2 particles. • Heterogeneous L1 2 particle structure obtained through simple two-stage heat treatment process. • The heterogeneous L1 2 particle reinforced alloy exhibits superior mechanical properties. [ABSTRACT FROM AUTHOR]

For zirconia continuous fibers, tensile strength is a very important performance parameter, which is affected by the crystal phase, its stability, grain size, processing temperatures, and so on. In this paper, the crystalline phases were adjusted through the Y 2 O 3 contents and heat treatment temperatures in the range of 1000–1500°C. We found that interfacial segregation of Y3+ at high temperatures led to crystal phase instability, which was observed near the grain boundaries of the 13.8YSZ fibers. At high temperatures, the grain growth of different fibers occurred to different degrees. The regularities between the tensile strength, the strength retention and temperature, Y 2 O 3 contents were discussed in detail. According to the highest tensile strength of a single fiber and Weibull modulus m, we found that the 5.4YSZ fibers were the most stable with the highest tensile strength and slow grain growth rate. The average strength was 1.6 GPa after heat-treating at 1500°C and the strength retention rate was about 54% under 1500°C for 60 min. Finally, the twistable 5.4YSZ continuous fibers with high strength were obtained by dry spinning technology. These results can provide reliable theoretical support and data sources for its high-temperature applications. • The twistable 5.4YSZ continuous fibers had a tensile strength of 1.6 GPa after 1500 °C. • Strength retention rate of 5.4YSZ continuous fibers was up to 54 % after 1500 °C/60 min • Crystalline phase was stable and grain growth was controlled through Y 2 O 3 content. [ABSTRACT FROM AUTHOR]

The utilization of kerf-loss silicon (KL-Si) waste as anode materials in lithium-ion batteries (LIBs) faces limitations of the rapid structural degradation during repeated charging/discharging. To overcome this limitation, 3D carbon-coated Si is constructed to buffer the Si volume expansion caused by the lithiation, while simultaneously forming a robust conductive network. Meanwhile, the well-dispersed porous carbon (C) shell, doped with suitable heteroatoms, plays a pivotal role in facilitating rapid ion transfer rates. In addition, a cobalt (Co) and nitrogen (N)-doped C shell is employed to encapsulate KL-Si, aimed at enhancing its lithium (Li) storage performances. The electrochemical performance of KL-Si@C-ZIF/N/Co composites, synthesized through the encapsulation of KL-Si with a metal-organic framework (MOF) structure (ZIF-90) followed by heat treatment. The resulting composites exhibit an outstanding reversible capacity of 981 mAh g−1 and an impressive capacity retention of 81.9% at 2 A g−1 even after 350 cycles. This paper presents a promising method for maximizing the value-added utilization of KL-Si and reveals the advantages of MOF-derived porous C shell in accommodating the inherent volume expansion of Si-based anodes. • This method achieves the highly value-added utilization of KL-Si. • The ZIF90-derived carbon coating in-situ encapsulates the KL-Si. • 3D porous C shells doped with N and Co elements improve the cycling performance of the KL-Si anode. • The KL-Si@C-ZIF/N/Co exhibits a high-capacity retention of 81.9% at 2 A g−1 after 350 cycles. [ABSTRACT FROM AUTHOR]