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Here, we report for the first time, a novel CrB/Cu(Al) composite is successfully fabricated by hot-pressed sintering of Cu and MAB phase Cr2AlB2 powders, which was prepared by a two-step molten salt method. The microstructure, mechanical properties and electrical conductivity of the composites were also investigated. Results show that homogeneous and compact composites composed of CrB and Cu (Al) solid solution are obtained, and the grain size of Cu matrix dramatically decreases from 56.41 to ~ 3 μm when Cr2AlB2 was added into Cu matrix. In addition, an alternate structure and good interfacial bonding between ceramic and Cu matrix are observed, which are beneficial for ceramic particles to bear loads and result in high mechanical strength. The Vickers hardness of Cu–20Cr2AlB2 composite is around 140 HV1.0 with electrical conductivity of 20.69% IACS. The tensile and yield strength of the composite are as high as 393.56–289.65 MPa, respectively. [ABSTRACT FROM AUTHOR]

Submicro-sized vanadium carbide (V2C) with orthorhombic structure prepared by the molten salt disproportionation method was firstly applied as an anode in lithium-ion batteries. The V2C has delivered a reversible discharge capacity of ~ 223.6 mAh·g−1 at 0.1 A·g−1 in the continuous 300 cycles without capacity attenuation and ~ 107 mAh·g−1 at 0.5 A·g−1 after 600 cycles with the capacity retention of 83.6%, respectively. Meanwhile, Li-ion storage mechanism of V2C is pseudocapacitive, accompanied with the redox reaction of V-ions during the Li-ions insertion/extraction process. The exploration of orthorhombic V2C may extend the selection of anode materials for lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Herein we report, a simple novel method to synthesize nanosized Ti3AlC2 powder from Ti, Al, and C powders in NaCl–KCl molten salt. It is more conducive to the formation of Ti3AlC2 at higher salt/precursor materials ratio and particle size of Ti3AlC2 powder dramatically decreases with increasing mass ratio of the salt to precursor materials. Fine-grained Ti3AlC2 powder is successfully synthesized at 950○C for 5 h or at 1000○C for 2 h with a salt/precursor materials ratio of 10:1. Ti3C2 MXene is also prepared by etching fine-grained Ti3AlC2 precursor in HF solution at 60°C for 2 h. It is the first time that nanosized ternary carbide Ti3AlC2 powder has been synthesized by a simple, high efficiency and relatively low-temperature process. [ABSTRACT FROM AUTHOR]

ZrB2 coating was synthesized by molten salt electrodeposition and its stability in molten zinc at 550 °C was investigated by static immersion tests. Macro morphologies, microstructures, phase and chemical composition of the uncoated and ZrB2‐coated 201 stainless steels after immersion in molten zinc for different periods were analyzed to evaluate their corrosion resistance. The results indicated that bare substrate suffered severe corrosion after several hours immersion in molten zinc and the corrosive products were composed of inner δ phase (Fe, Cr)Zn7 and outer ζ phase (Fe, Cr)Zn13. As a contrast, ZrB2 coating acted as an effective barrier against the invasion of molten zinc and greatly improved the corrosion resistance of the substrate materials. The results may provide a potential way to design ZrB2‐based ceramic coatings for corrosion protection in molten zinc environment. ZrB2 coating that adhered well to the steel substrate has been prepared by electrodeposition in NaCl‐KCl‐K2ZrF6‐KBF4 molten salts and its stability in molten zinc at 550 °C has been investigated. The obtained results indicate that ZrB2 coating can effectively protect the substrate from invasion by molten zinc, which provides a new point of view for coating solutions in molten zinc corrosion. [ABSTRACT FROM AUTHOR]

Ferritic stainless steels are promising materials for solid oxide fuel cell interconnect applications. However, volatilization of Cr from the Cr-containing oxide scales can result in cathode poisoning, especially in wet air, and thus greatly degrades the performances of the cell. In the present study, a protective and adhesive NiFe2O4 spinel coating was applied on a type 430 stainless steel (430SS) to isolate Cr2O3 from gas environment. The performance of the uncoated and NiFe2O4-coated samples has been evaluated in the air-7%H2O at 700, 800, and 850 °C, respectively. The bare steel lost mass at 700 and 800 °C and underwent breakaway oxidation at 850 °C after ~ 75 h, including scale spallation and Cr evaporation. The NiFe2O4 coating could significantly increase the oxidation resistance of 430SS and effectively retard the outward diffusion of Cr and inhibit the Cr evaporation. [ABSTRACT FROM AUTHOR]