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304 austenitic stainless-steel (SS) strip-based carbon fiber metal laminates (CFMLs) have raised significant concerns, in terms of their mechanical performance. On top of that, the hybrid laminates' interlamination performance is vital in regulating their failure patterns. Along these lines, in this work, SS strips with regulatable micromorphology and composition were obtained by using physical and chemical surface modification strategies, including polishing, acid etching, anodization, and thermal treatment. The shear strength of the treated-SS/epoxy single lap joints (two treated-SS strips bonded by the epoxy resin via hot curing process) was systematically explored, and the origins of the enhancement mechanism were attributed to the resulting surface microstructure, as well as the possible chemical reactions between the treated surface and the curing agent. The etching-anodizing-thermally treated-SS (EAT-SS)/epoxy joint exhibited the maximum shear strength (16.04 MPa) and work of fracture (5.85 kJ·m−2) due to the substantial cohesive failure pattern of the epoxy. The encouraging enhancement was mainly attributed to the synergistic effect of the micro-annular pit and the nanoporous array structure of the EAT-SS surface. These effects induced a significant mechanical interlock and a plausible chemical reaction at the interface, which led to improved bonding strength between the epoxy and treated-SS surface. Overall, in this work, it was demonstrated that the combination of the anodization and thermal treatment can effectively improve the interlamination bonding properties between the SS strip and the epoxy resin due to the combination effect of mechanical interlocking and chemical bonding. [ABSTRACT FROM AUTHOR]

In order to explore the mapping recognition of arc welding molten pool characterisation and penetration state, according to the idea of embedded system construction, this article adopts the idea of software and hardware co‐design to find the zero‐crossing point of the second derivative in welding image edge detection, and give a threshold. When the absolute value of the first‐order derivative exceeds the threshold and has a different sign with the first‐order derivative of the previous edge, it is judged as a valid edge. The welding current adopts a symmetrical pulsed AC square wave, and the proportion of heat flow input is high. At the base current, the arc light is darker, so a clear image is obtained. This article designs a simulation experiment to verify the effect of the embedded system in this article. From the experimental research, it can be known that the embedded system constructed in this article can play a certain role in the mapping recognition of the arc welding molten pool characterisation and penetration state. [ABSTRACT FROM AUTHOR]

The sodium battery is one of the best energy storage technologies due to its abundant resource reserves and excellent energy storage ability. As a two-dimensional layered transition metal, molybdenum selenide (MoSe2) has large interlayer spacing and a high theoretical capacity (470 mAh∙g−1). Its structure is suitable for the negative electrode of sodium-ion batteries, with a large ionic radius and slow ion diffusion kinetics. However, it is difficult for the rate capability and cycling performance of MoSe2 to meet practical needs due to a weak intrinsic electron transport ability and volume expansion during sodium absorption. The hydrothermal synthesis method was used to synthesize the MoSe2 complex based on boron and nitrogen dual-doped 3D carbon fibers obtained from bacterial cellulose membranes (MoSe2/N&B-BCM) for sodium batteries. Additionally, electrochemical analysis and experimental characterization were performed. In summary, the experimental analysis shows that MoSe2/N&B-BCM has excellent conductivity, structural integrity, cyclability (328 mAh∙g−1 after 100 cycles at a 0.5 c constant rate), and rate stability. [ABSTRACT FROM AUTHOR]