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To investigate the problems of overload and excessive thermal insulation associated with building electrical fires caused by wires, a theoretical model of wire heat transfer is established, and the pyrolysis and combustion phenomena of the insulation layer are analyzed. The results showed that the temperature evolution of the wire underwent three stages: constant temperature, insulation heating, and high‐temperature pyrolysis. The insulation layer experiences bulging, exhausting, carbonization, dripping, and burning in sequence, and insulation layer dripping requires at least 160 A of current. As the current increases, the temperature increase rate of the wire increases gradually, and the fusing time of the wire gradually decreases. Under the same current, 160°C is the turning point at which the temperature increases. The temperature increase rate of the copper wire is greater than that of the aluminum alloy wire, and the temperature increase rate of the bare wire is greater than that of the insulated wire. The fusing time of an aluminum alloy wire is less than that of a copper wire, and the fusing time of a bare wire is less than that of an insulated wire. The research results provide theoretical guidance for the prevention and investigation of building electrical fires. [ABSTRACT FROM AUTHOR]

In this letter, a method for designing a Doherty power amplifier (DPA) using bare die and bonding wires (BWs) is proposed. This method adjusts the geometric parameters of BWs to achieve the desired transmission characteristics, allowing BWs to actively participate in the formation of the matching network, thus realizing the codesigning of the DPA and BWs. By designing appropriate BWs compensation to mitigate the intrinsic parasitics of bare die, the inherent obstacles caused by transistor parasitic effects are mitigated. This strategy offers a distinct advantage in terms of concurrently adjusting the target load impedance and phase, leading to a streamlined DPA design process. At the same time, the nonclipping impedance region is expanded, which attenuates the nonlinear effects of parasitic effects. On the basis of the proposed methodology, a DPA operating at 3–4 GHz is designed. Measured results show that the DPA achieves a saturation output power of 42.4–43.6 dBm in the operating band, accompanied by a drain efficiency of 55%–66%, while achieving 42%–54% at 6 dB output back‐off level. [ABSTRACT FROM AUTHOR]

In recent years, flexible electronics technology has been developing rapidly, and flexible electronic devices have been widely used in wearable gadgets and robotics. Flexible wires are the basic components of these devices, which usually consist of metallic materials with flexibility and ductility. However, the introduction of flexible conductive materials has broadened the application scope of flexible wires. In this paper, PDMS/SCF conductive composites exhibiting different conductivity properties on both sides are fabricated by adding meshes based on the continuous spatial‐confining network assembly method. The conductivity of PDMS/SCF (6 wt%) composites can be exhibited as 173.45 S/m in the conductive layer and 6.25 × 10−11 S/m in the insulating layer, which can be used as core and surface layers of conductors, respectively. A mathematical model is also developed to predict the electrical conductivity of the PDMS/SCF conductive composites, and the experimental data are in good agreement with the predicted results. This work provides a method for the continuous preparation of multifunctional composites that can be molded in one step with conductive layer and insulating layer, which can be used as the core and insulating layers of wires, thus simplifying the preparation process of composite‐based wires and expanding the range of conductive composites applications. [ABSTRACT FROM AUTHOR]

Mechanically flexible and stretchable inductive coils are critical for enabling communication, sensing, and wireless power transfer capabilities in wearable electronics that conform to the body for healthcare and Internet of Things (IoT) applications. Leading stretchable conductors such as liquid metals (LMs) offer conformability but sacrifice electromagnetic performance compared with Cu wires, leading to lossy radio‐frequency (RF) characteristics. Here, a strategy leveraging multistranded 3D woven 'litz' transmission lines is presented to amplify the resonant RF performance of LM inductors. Through comprehensive simulations and experiments, it is discovered that interwoven LM litz wires boost the Quality Factor (Q) by 80% compared to standard liquid metal wires. A fabrication methodology is also demonstrated for stretchable coils that retain high Q (>30), outperforming the previously reported LM coils and maintaining 98% of their wireless transmission efficiency under up to 30% biaxial strain. Moreover, the versatility of this approach is showcased by 3D printing four‐terminal 'choke' inductors optimized for RF filtering and inductance tunability, overcoming the fabrication limitations of traditional planar printed electronics. These results offer valuable insights into the design and implementation of 3D‐printed inductors for a diverse suite of electromagnetic device applications. [ABSTRACT FROM AUTHOR]

Summary: PVD Coatings Enable Textile Wires and Sensors – Process control by adjusted energy ranges Plasma sputtering deposition is a Physical Vapor Deposition (PVD) method based on a weakly ionized gas, the plasma, that ablates atoms from a solid target material at vacuum conditions to deposit the sputtered atoms on a substrate. In this way, the plasma has two functions, i) the generation of high‐energy ions of several 100 eV accelerated to the target for sputtering, and ii) to support film growth by plasma‐surface interaction with particles bearing lower energies around ∼10 eV. For both processes, energy thresholds are present, which will be discussed in this article. Plasma sputtering deposition has wide spread industrial applications. As one example, the metallization of polymer fibers is demonstrated to obtain electrically conductive textile sensors and wires. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between the microstructure and the mechanical properties and the residual stresses of thermomechanically rolled, butt‐welded S1100MC ultra high‐strength steel plates. Matching metal‐cored filler wires are used for metal active gas welding of the plates in horizontal and vertical‐up positions. The effect of the heat input on the microstructures of both the weld metal (WM) and the heat‐affected zone (HAZ) is studied in detail. The microstructure of the WM consists of different types of ferrite, but the microstructure of the HAZ predominantly consists of fresh martensite at the top and bottom areas. Structure and size of the prior austenite grain boundaries are dependent on the welding positions and affect the impact toughness of the welds. HAZ of the weld produced in vertical‐up position is under intensive tensile residual stresses next to the fusion line. Even with matching filler wires, the strength of the welds is insufficient, and fracture of the weld metal occurs because the extended cooling time leads to the formation of acicular ferrite instead of martensite. [ABSTRACT FROM AUTHOR]

The conditions for the growth of polycrystalline GeSn films on SiO2/Si(001) substrates by hot wire chemical vapor deposition are determined for the first time. The effect of the introduction of Sn into the Ge lattice on the morphology, structure, and transport properties of films is studied. GeSn films obtained at 300 °C have a uniform surface with a roughness of less than 1.0 nm. It is shown that the introduction of 5% Sn allows, without the use of recrystallization annealing, to significantly increase the hole mobility of polycrystalline GeSn films from 20 to 60 cm2 V−1 × s−1. despite the small grain size of 35 nm. Such films are of great interest for creating thin‐film transistors for active matrices' liquid crystal displays. [ABSTRACT FROM AUTHOR]

The microstructure, texture, and dislocation configuration of cold‐drawn pearlitic steel wires were investigated by scanning electron microscopy (SEM), electron backscattering diffraction (EBSD), and transmission electron microscopy (TEM). In addition, Fe/Fe3C interface structure at the atomic level was clearly observed and analyzed by high‐resolution TEM (HRTEM), and the microscopic deformation mechanism of cementite lamellae at different drawing strains is revealed. The results show that pearlite lamellae turn to the drawing direction to form ferrite <110> fiber texture, and the cementite and ferrite lamellae are simultaneously thinned with the increase of drawing strain. During the cold drawing process, shear‐bands(S‐bands) are formed in the cementite lamellae; the dislocation of ferrite transits from single slip to multi‐slip stage, and the dislocation density increases. After drawing, the lattice structures of cementite and ferrite phases show the evolution from single‐crystal to polycrystal, and the cementite lamellae are divided into a multilayer structure: central relative large‐size cementite crystal and outside relative small‐size cementite crystal layer; the dissolution of cementite lamellae in some regions results in the lattice expansion of ferrite phase and the occurrence of neck‐down regions in the cementite lamellae. [ABSTRACT FROM AUTHOR]

A novel multi‐conductor electromagnetic coupling model for the sensitive‐wire subject to driven wire in a high‐precision machining workbench is proposed in this paper. The general coupling model for an N‐wire system is derived and is used to evaluate the wire coupling effect. Furthermore, 4‐wire and 3‐wire models are demonstrated to verify the accuracy through full‐wave electromagnetic simulation below 10 MHz. The results show that the error between the proposed method and the full‐wave electromagnetic simulation is less than 10%, demonstrating the high efficiency and accuracy of the proposed method. When the parameters of the driven power wire and the most sensitive wire are fixed and the parameters of neighboring wires are swept, the maximum fluctuation of the induced current on the most sensitive wire is 6.1 dB. The efficient calculation method proposed in this work helps reduce the risk of electromagnetic interference in complex electronic systems and improves the design efficiency of wires. It is promising to become a high‐performance method with high efficiency and precision. [ABSTRACT FROM AUTHOR]

Organic field‐effect transistors (OFETs) have been extensively studied over the past decades because of their suitability for low‐cost, large‐area, and flexible electronics. However, improvements are needed to satisfy the demands of high‐speed applications. The switching speed of a logic device is affected by the charge‐carrier mobility (µ) and the square of the channel length (L) at a given gate–source bias. Therefore, increasing µ and/or reducing L are crucial for achieving high‐speed OFET‐based digital circuits. In this study, an n‐type OFET is fabricated with increased switching speed via a dual‐role approach involving solution‐grown, highly ordered single‐crystalline N,N'‐dioctyl‐3,4,9,10‐perylenetetracarboxylic diimide (PTCDI‐C8) wires, which serve as a mask for short‐channel formation up to the microscale and an active layer with enhanced charge mobility. Additionally, the performance of the n‐type short‐channel OFET and resistive‐load‐type inverters is evaluated. For comparative purposes, long‐channel (50 µm) devices with PTCDI‐C8 wires and short‐channel devices with a PTCDI‐C8 film are fabricated and the device performance is analyzed. The short‐channel device with the PTCDI‐C8 wires exhibits a significantly higher switching speed. Thus, the dual‐role approach is a simple and straightforward method for fabricating short‐channel devices, paving the way for further advancements in OFET technology requiring high switching speeds. [ABSTRACT FROM AUTHOR]

Nowadays, in view of the increasingly serious problems of electromagnetic interference (EMI) and radiation pollution, smart EMI shielding materials with tunable shielding effectiveness (SE), especially "On/Off" switchable capability, are highly desirable. Herein, Co‐based amorphous wires (AWs) with excellent soft magnetic and mechanical properties are regularly arranged on a 3D‐printed mold as tunable EMI shielding composites. The EMI SE can be easily tuned in the range of ≈0.6–24.7 dB by way of rotation, which has been confirmed to be an effective way to achieve free tuning of EMI SE by simulation. In addition, by compositing AWs with reduced graphene oxide and constructing a double‐layer structure with a gap of 1/4 wavelength in the X‐band, a much wider SE tuning range of ≈1.0–57.7 dB is further realized. The representative "On/Off" switchable shielding capability that can switch between EM transmission and effective shielding, together with the wide SE tuning range larger than 50 dB, shows the great potential of Co‐based AW composites in smart EMI shielding applications. [ABSTRACT FROM AUTHOR]

To accurately describe the heat transfer and melting characteristics of a calcium‐cored wire in molten steel, the finite difference method is used in theoretical calculations to solve the relationship between the melting temperature, radius, and time. Numerical simulations are performed using the Eulerian–Eulerian method to characterize the temperature distribution at different periods. The results show that the radius of the calcium wire and steel shell both decrease and the melting rate gradually increases. The calcium‐cored wire has a fish‐scale temperature distribution, with the temperature decreasing from a maximum at the front down to the tail end and increasing outward from the center axis. The temperature of the wire core is 1120 K at 0.272 s, indicating the complete melting of the pure internal calcium. The temperature of the calcium wire–steel shell interface reaches 1793 K at 0.979 s and remains from 1645 to 1757 K at the front of calcium wire. The steel shell melts through, and calcium flows into the molten steel in liquid form. The numerical simulation results generally agree with the theoretical calculations, and the reliability of the model is verified by comparison with published studies. [ABSTRACT FROM AUTHOR]

A plasma haloscope has recently been proposed as a feasible approach to extend the search for dark matter axions above 10 GHz (≈40 μ$\umu$eV), whereby the microwave cavity in a conventional axion haloscope is supplanted by a wire array metamaterial. Since the plasma frequency of a metamaterial is determined by its unit cell, and is thus a bulk property, a metamaterial resonator of any frequency can be made arbitrarily large, in contrast to a microwave cavity which incurs a steep penalty in volume with increasing frequency. To assess the actual potential of this concept as a practical dark matter haloscope, the basic properties of wire array metamaterials have been investigated through an extensive series of S21 measurements in the 10 GHz range. This report presents some new systematics of wire array metamaterials themselves including the approach to full plasmonic behavior, the applicability of the semianalytic theory of Belov, and estimates of the loss term which bode favorably for the plasmonic haloscope application. This present work constitutes the first precision test of the semianalytic theory of Belov et al., for which the predicted plasma frequency agrees with the experimental value at the 0.1% level. [ABSTRACT FROM AUTHOR]

This paper presents an electromagnetic analysis of a moving infinitely long line source illuminating an infinitely long metallic wire at rest. The study uses the full‐wave numerical finite difference time domain (FDTD) method, which is based on the spatial and temporal discretization of Maxwell's equations. Movement is computed within the FDTD technique by varying the position of the line source at each time loop. An analogy is proposed between the wavelength spectrum of the simulated electromagnetic field and the Compton scattering experiment. A good agreement is obtained between theoretical analysis, numerical results, and Compton experimental data. [ABSTRACT FROM AUTHOR]

A hemispherical‐shaped folded electrically small antenna (ESA) is a well‐known antenna where the radiating conductor is a wire or flat strip of variable width. This work analyzed the performance of strip‐based ESA for a constant strip width and focused on the fabrication procedure which utilizes the low‐cost dielectric material and ubiquitous 3‐D printer. The impact of additional dielectric support on the performance of ESA was investigated. This work also introduced conductive paint for the radiating part, along with metallic wire and strip. There is a good agreement between simulated and measured results. The 3‐D printing technique offers design flexibility, eases fabrication difficulty, reduces material cost, and improves the mechanical stability of the antenna. [ABSTRACT FROM AUTHOR]

This paper presents a broadband, high linearity 7‐bit digital step attenuator (DSA) using a low‐cost bonding wire package. Capacitive compensation technique is proposed to offset the deterioration of attenuation accuracy and operating bandwidth caused by the parasitic parameters of the bonding wire and switching transistors. And the negative voltage bias technique (NVBT) is proposed to improve the linearity of the DSA. Based on the capacitive compensation technique and the NVBT, a 7‐bit DSA is implemented using a 0.13 µm Silicon‐On‐Insulator (SOI) process with a low‐cost bonding wire package. The DSA achieves broadband operation with an insertion loss (IL) of 2.7 dB at 7 GHz and root mean square (RMS) amplitude error less than 0.5 dB at DC‐7 GHz. The input P1 dB of all states is better than 31.7 dBm. [ABSTRACT FROM AUTHOR]

Cold metal transfer (CMT) is a variant of gas metal arc welding (GMAW) in which the molten metal of the wire is transferred to the weld pool mainly in the short‐circuit phase. A special feature here is that the wire is retracted during this strongly controlled welding process. This allows precise and spatter‐free formation of the weld seams with lower energy input. To simulate this process, a model based on the particle‐based smoothed particle hydrodynamics (SPH) method is developed. This method provides a native solution for the mass and heat transfer. A simplified surrogate model was implemented as an arc heat source for welding simulation. This welding simulation model based on smoothed particle hydrodynamics method was augmented with surface effects, the Joule heating of the wire, and the effect of the electromagnetic forces. The model of metal transfer in the cold metal transfer process shows good qualitative agreement with real experiments. [ABSTRACT FROM AUTHOR]

The collection of single‐photon emission from a quantum dot (QD) in a Bragg waveguide through a photonic wire bond (PWB) via free‐space resonant frequency pumping at 1.6 K is demonstrated. The in‐fiber single photons show a small multiphoton contribution, quantified by a low second order photon autocorrelation value of gcorr(2)(0)=(5.9±0.8)×10−3$g_{{\mathrm{corr}}}^{(2)}\;(0) = ({5.9 \pm 0.8})\; \times {10^{ - 3}}$ (background‐corrected) or graw(2)(0)=(9.5±1.4)×10−2$g_{{\mathrm{raw}}}^{(2)}(0)\; = ({9.5 \pm 1.4})\; \times {10^{ - 2}}{\mathrm{\;}}$(raw data). The decay time of the QD is measured to be τ=440${\mathrm{\tau \;}} = {\mathrm{\;}}440$ ps. The PWB obviates the need for in‐cryostat alignment of the single‐photon source with an optical fiber and thus offers a route to scalable integration of quantum photonic devices in a cryogenic environment. Uniquely, the approach combines the QD‐waveguide technique, enabling resonant driving of individual QDs without the need for cross‐polarization filtering, and the PWB for deterministic, alignment‐free coupling of single‐photon sources to optical fibers. [ABSTRACT FROM AUTHOR]

The manufacturing industry has witnessed advancements in soft robotics, specifically in robotic grippers for handling fragile or irregular objects. However, challenges remain in balancing shape compliance, structural rigidity, weight, and sensor integration. To address these limitations, a 3D‐printed multimaterial gripper design is proposed. This approach utilizes a single, nearly fully automated 3D printing process to create a universal gripper with almost no assembly work. By processing functional polymer, polymer nanocomposite, and metal wire simultaneously, this technique enables multifunctionality. The gripper achieves different gripping configurations by adjusting joint stiffness through Joule heating of conductive polylactic acid material, ensuring shape conformance. Embedded metal wires, created using an in‐house wire embedding technique, form reliable high‐current‐loading interconnections for the conductive joints acting as the heater. Additionally, an integrated soft sensor printed in thermoplastic polyurethane (TPU) and conductive TPU detects compression levels and discerns handled samples. This study showcases the potential of 3D multimaterial printing for on‐demand fabrication of a smart universal gripper with variable stiffness and integrated sensors, benefiting the automation industry. Overall, this work presents an effective strategy for designing and fabricating integrated multifunctional structures using soft, rigid, and conductive materials, such as polymer, polymer nanocomposite, and metal through multimaterial 3D printing. [ABSTRACT FROM AUTHOR]

The overcurrent fault of copper wire is an important cause of electrical fire, and the combustion process of which is relatively complicated. In this study, the rated current of 32A of the wire was taken, and the electrical fault simulation device was used. After the overcurrent Io was set to 128A, 160A, 192A, and 224A, respectively, to analyze the combustion evolution process of PVC‐insulated copper wire, the evolution of pyrolysis gas from the insulating layer, and the change of functional groups. The results show that when the overcurrent fault of PVC‐insulated copper wire happened, the core wire was turning red, the wire was deforming, the smoke was releasing, the insulating layer was dripping, the wire was fusing, and the continuous burning occurred. When the current Io < 160A, there was only one fusing point on the wire. In addition, when an overcurrent fault occurred in the PVC‐insulated copper wire, the temperature rise rate increased exponentially, which can be divided into three stages of the initial heat accumulation stage, the wire fusing stage, and the continuous burning stage. Furthermore, CO, HCl, CH4, olefins, and aliphatic and aromatic compounds were precipitated during the combustion process of the PVC insulating layer. The quality of the insulating layer decreased with the increase in temperature, and the weight loss rate was higher at 300°C. The conclusions of this study have provided experimental basis and technical support for the physical and evidence identification of fire accidents. [ABSTRACT FROM AUTHOR]

The thermal damage mechanism of Al wires for long‐distance overhead transmission under extreme service conditions is an important scientific issue that restricts the design and development of high‐performance Al wires. In this study, the thermal damage mechanism of the Al–Zr–Er alloy wires with a good combination of ultimate tensile strength in 170.0 MPa and electrical conductivity in 61.42% IACS is investigated via a simulated high‐temperature service experiment. In the results, it is shown that strength evolution exhibits a negative exponential pattern mainly attributed to the partial dislocation recovery in the cold‐drawn Al wires based on the quantitative calculation. However, the nanoscale Al3(Zr, Er) precipitates exhibit good thermal stability. The strength residual rate of the Al–Zr–Er alloy wires exceeds 90% after the simulated high‐temperature treatment at 280 °C, which can be attributed to the strongly pinning effect of nanoscale Al3(Zr, Er) precipitates on the dislocations and the grain boundaries, finally leading to the larger Zener drag force as compared with the driving force for recrystallization, thereby achieving good heat resistance of Al–Zr–Er alloy wires. [ABSTRACT FROM AUTHOR]

1D semiconductor wires have great potential in on‐chip integrated photonics systems. However, it is still challenging to efficiently integrate various semiconductor wires on a large scale for complex functional devices. This study reports a universal route to in‐plane integrate unidirectional metal halide perovskite CsPbBr3 wire arrays with Sb2Se3, PbSeand CdS wires on mica substrates, respectively. It is found that the growth of the unidirectional wire arrays is controlled by a synergistic effect of the promoted initial nucleation on the transferred heterogeneous wires and the thermodynamically favored epitaxy on mica. The optical characterizations show that the CsPbBr3 wire arrays can act as both the light emitting media and waveguide, where the emission in the CsPbBr3 wires can be efficiently guided into the backbone Sb2Se3 wire. Importantly, the constructed CsPbBr3 waveguide arrays/Sb2Se3 wire photodetector system shows 73.4 nA photocurrent with the on/off ratio of 111, by exciting the CsPbBr3 wires at 174 mW cm−2 of 405 nm laser. The frequency dependent photoresponse characterizations exhibit a response capability of 2000 Hz modulated laser pulse and a 3 dB frequency above 300 Hz, indicating the rapid response speed. This study promotes the application of semiconductor wires in on‐chip multifunctional integrated photonic devices. [ABSTRACT FROM AUTHOR]

Recent advancements have shown great promise in utilizing wire‐fed direct energy deposition (DED) for building aluminum alloy structures. However, utilizing the wire‐fed DED approach for fabricating metal matrix composite structures remains a significant challenge. Herein, a wire‐based additive manufacturing process is used to successfully produce a 1D boron nitride nanotube (BNNT)‐reinforced aluminum composite with high strength. Al‐BNNT electrode is developed in house. The microstructural changes that occur during layer‐by‐layer deposition are investigated. The grain morphology changes from equiaxed grains in the bottom layer to columnar grains in the top layer. BNNTs act as nuclei to promote the formation of equiaxed grains and interfacial compounds (AlN and AlB2) during solidification. This results in improved strength, with Al‐BNNT composite exhibiting a tensile strength of 47 MPa, 2.3 times higher than its pure Al. Higher strength is attributed to the retention and uniform distribution of BNNT reinforcement in the melt pool, leading to effective load transfer. This study demonstrates the potential of additive manufacturing for producing high‐performance metal matrix composites with novel 1D reinforcements and improved multifunctional properties. [ABSTRACT FROM AUTHOR]

Liquid metal (LM) is of great use in many fields (e. g., sensors, biology, electronic circuits). With special mobility, high surface tension and excellent electrical conductivity, it can play a role in the field of flexible electronics. Due to its surface tension, it easily shrinks into a spheroid shape. Especially under the same current condition, the shrinkage of the volume will lead to open circuit, so it is very difficult to produce stable liquid metal ultrathin, ultrafine wire, which has become a barrier limiting the use of liquid metal. In this work, LM is mixed with polydimethylsiloxane to form a micrometer‐thick conductive layer by free deposition. The LM is located inside the polymer holes. Not only that, microcircuits are also mapped on the surface of LM deposits. It not only has excellent electrical conductivity, but also has good flexibility. This work explores a simple method to produce a ultrathin conductive film and reduce the size of electronic components, which has potential applications in integrated circuits. [ABSTRACT FROM AUTHOR]

Steel seven‐wire strands are highly vulnerable to corrosion phenomena, which can strongly reduce their strength and ductility capacities. Following several parametric studies already conducted on corroded wires and strands, which allowed to identify the key parameters that govern their mechanical behavior, this paper presents a new resistance model for corroded seven‐wire strands. The model introduces a new coefficient that takes into account the variability of the corrosion in the seven wires that constitute the strand, with the purpose of representing the dispersion in the peak strength often emerged from tensile tests available in the literature. The lower bound of this coefficient is estimated analytically considering a brittle behavior for the wires. The ductile behavior is then taken into account by means of several Monte‐Carlo simulations of corroded strands. Finally, the resistance model allows to define strength reduction curves that allow to estimate the strength of corroded strands taking into account both the geometry of the corrosion and the steel material parameters. They represent simple engineering tools that are of great interest from both a design and safety assessment point of view. [ABSTRACT FROM AUTHOR]

This article presents the importance of non‐destructive testing (NDT) in maintaining the safety and functionality of bridge cables, and focuses on the practical use of magnetic‐inductive testing (MIT) and ultrasonic testing (UT) for NDT of bridge cables in free length and in the area of the end connectors. MIT is a non‐invasive method that can effectively detect defects such as broken wires, corrosion symptoms, and other imperfections, making it a promising technique for inspecting and maintaining bridge cables. A research project investigated various types of magnetic induction testing on different tension members made of single wires and evaluated the advantages and limitations of the MIT method. The study also explored the impact of factors such as cable diameter and measurement speed on the effectiveness of the technique. The results suggest that the MIT method can accurately detect defects in bridge cables and provide valuable information for maintenance and repair purposes. However, the article highlights the need for further research to optimize the MIT technique, particularly in automating the detection and characterization of signals, and to expand its applicability to a wider range of cable diameters and conditions. [ABSTRACT FROM AUTHOR]

The design and performance of optimised wire and arc additively manufactured (WAAM) rectangular hollow section (RHS) beams, with varying material strengths and thicknesses along their lengths, are investigated in this study. Simply‐supported beams under three‐point bending were considered. Size optimisation of the RHS beams was carried out by fixing the nominal outer profile and varying the local thicknesses and steel grades in discrete steps to accommodate the variation of the bending moment along the member length. Two optimised beam specimens were manufactured via WAAM and tested, and were shown to have excellent load‐carrying capacities at greatly reduced self‐weights compared with the conventionally manufactured beams, indicating a considerable increase in their structural efficiency. This study confirms the feasibility of combining materials with different thicknesses and steel grades using WAAM, which provides structural engineers with further design freedom and opportunities to minimise material use. [ABSTRACT FROM AUTHOR]

Within the framework of the development of the second generation of Eurocode 3, Part 1‐11, related to the design of steel tension components, was completely revised. This paper introduces the main developments in the prEN 1993‐1‐11:2023 regarding the basis of design for the three groups of tension components: A ‐ Rods, B ‐ Ropes, and C ‐ Parallel strand or wire systems. For each of the three groups, complete information on the "Material", "Ultimate limit state" (including fatigue) and "Serviceability limit state" requirements are provided. Improved formulas for the design of saddles and clamps are presented, including new saddle solutions for group C. Reference is made to the new group D ‐ Parallel wire tension components for suspended structures, included in new Annex C. Annex A "Product requirements for tension components" was completely revised to reflect modern testing requirements. Informative Annex B has been also updated with new figures that reflect the state of the art in tension elements and terminations. [ABSTRACT FROM AUTHOR]

Saddle systems are a popular method for supporting the cables at the pylons of cable‐stayed bridges. Fretting fatigue failure of bridge stay cables is a major design consideration for saddle systems. Current design provisions require large‐scale tests of these anchoring systems. However, such tests are costly and time‐consuming. With this in mind, the current paper presents a small‐scale fretting fatigue setup to evaluate the fretting fatigue behavior of bridge stay cable wires at saddle supports. In this paper, fretting tests are conducted on bare and galvanized wires. Hourglass samples are then used to evaluate the material properties and plain fatigue performance of the studied wires. Finally, the microstructure of the wires is evaluated, and the influence of defects on the fretting fatigue life of the wires is discussed. Highlights: A small‐scale fretting fatigue test setup for bridge stay cable wires is designed.Fatigue and fretting fatigue performance of bare and galvanized wires are evaluated.The microstructure and properties of two typical bridge cable wires are explored.The effects of defects on fatigue and fretting fatigue life of wires are discussed. [ABSTRACT FROM AUTHOR]

Demands for effective high‐temperature electrical conductors continue to increase with the rapid adoption of electric vehicles. However, the use of conventional copper‐based conductors is limited to relatively low temperatures due to their poor oxidation resistance and microstructural instability. Here, a highly conductive and thermally stable nickel‐graphene‐copper (NiGCu) wire that combines the advantages of graphene and its metallic components is developed. The NiGCu wire consists of a conductive copper core, an oxidation‐resistant nickel shell, and axially continuous graphene embedded between them. The experiments on 10–80 µm diameter NiGCu wires demonstrate substantial enhancements in electrical properties and thermal stability across a variety of metrics. For instance, the smallest NiGCu wires have a 61.2% higher current density limit, 307.6% higher conductivity, and an order of magnitude smaller change in resistivity compared to conventional Ni‐coated Cu counterparts after annealing at 650 °C. By performing both innovative experiments and simulations using different sizes of NiGCu wires, the diffusion coefficients of metals are quantified, for the first time to the best knowledge, through continuous graphene. These results indicate that the dramatic improvement in thermo‐electrical properties is enabled by the embedded graphene layer which reduces NiCu interdiffusion by ≈104 times at 550 °C and 650 °C. [ABSTRACT FROM AUTHOR]

Maximizing hole‐transfer kinetics—usually a rate‐determining step in semiconductor‐based artificial photosynthesis—is pivotal for simultaneously enabling high‐efficiency solar hydrogen production and hole utilization. However, this remains elusive yet as efforts are largely focused on optimizing the electron‐involved half‐reactions only by empirically employing sacrificial electron donors (SEDs) to consume the wasted holes. Using high‐quality ZnSe quantum wires as models, we show that how hole‐transfer processes in different SEDs affect their photocatalytic performances. We found that larger driving forces of SEDs monotonically enhance hole‐transfer rates and photocatalytic performances by almost three orders of magnitude, a result conforming well with the Auger‐assisted hole‐transfer model in quantum‐confined systems. Intriguingly, further loading Pt cocatalyts can yield either an Auger‐assisted model or a Marcus inverted region for electron transfer, depending on the competing hole‐transfer kinetics in SEDs. [ABSTRACT FROM AUTHOR]

Excellent plastic forming ability is a prerequisite for large-scale production of steel wires in engineering application. The process of traditional steel wire production inevitably needs interannealing treatment and corrosion-resistant surface treatment (such as hot-dip galvanizing), consuming a large amount of energy and causing environmental pollution. Herein, a rod of 6.34mm in diameter, made of Fe35Ni35Cr20Mn10 high-entropy alloy (HEA), is continually cold drawn to 0.08mm wire without interannealing, reaching an accumulated strain of 8.73 and a section reduction ratio of 99.98%. The mechanical properties are examined by CMT5105 or CMT4503 tensile tester. The microstructure was characterized by scanning electron microscopy (FEI Sirion-400) and transmission electron microscopy (FEI Tecani G2 T20). The wire of 0.08mm in diameter possesses a high strength of 1868 ± 13 MPa. The formation of nanotwins or twin-groups between the lamellar structures and inside the lamellar structure during cold-drawing can harmonize the deformation between the lamellar structures and between grains in a lamellar structure that guarantee the continual plastic deformation. The high strength of the prepared HEA wires is related to the great increase in dislocation density, the formation of nanotwins, and hard <111> texture and the refinement of lamellar structures. [ABSTRACT FROM AUTHOR]

Intelligent composite structures are designed to retard crack initiation and growth in a controlled manner using shape memory alloys (SMAs). The crack closure under mixed‐mode I/II conditions in the 3D‐printed specimens reinforced with pre‐strained SMAs is investigated using numerical, analytical, and experimental procedures. The stress intensity factors (SIFs) of the semicircular bending (SCB) samples are theoretically estimated based on the micromechanical model where the wires are entirely perpendicular to the crack planes, and findings are verified with those data obtained using numerical and experimental methods. Stable crack growth, interlayer adhesion, and fracture toughness improvement are obtained in the modified test samples. In terms of strength and fracture toughness, SMA with 1% pre‐strain is introduced as an optimal value in both pure mode I and mixed‐mode I/II conditions. Highlights: FDM 3D‐printed cracked samples are reinforced with SMA wires to retard crack initiation.Three different pre‐strains of 1%, 2%, and 4.3% are used in the current experiment.SMA wires could be used to enhance the fracture toughness of 3D‐printed structures.Stable crack growth, interlayer adhesion, and fracture toughness improvement are seen. [ABSTRACT FROM AUTHOR]

Metallic nanowires (NWs) exhibit a number of interesting properties, such as high conductivity, flexibility, and cold‐weldability, making them ideal for nanocircuits. They are usually adsorbed on substrates by depositing a colloidal solution of NWs on the surface. However, they remain randomly scattered and solvent residues may contaminate/ degrade the sample. This study presents a method for forming electrical contacts with gold nanowires based on all‐dry deterministic transfer. The process begins with the adsorption of gold nanowires by drop casting the colloidal solution onto a viscoelastic substrate. These wires are transferred to selected locations on the substrate, minimizing manipulation with fabrication times a factor of 2 shorter than direct drop casting deposition, preserving surface and sample conditions, and improving the fabrication of nanocircuits. Atomic force microscopy is used to manipulate the NWs for the final connections, which have contact resistances of a few ohms. To illustrate the technique, three different examples of applicability are presented. This work is expected to be a starting point for expanding the potential of deterministic transfer that is successfully used in 2D materials. For example, to study local electrical transport in heterogeneous samples such as van der Waals heterostructures and twisted layers of 2D materials. [ABSTRACT FROM AUTHOR]

Indications of corrosion were observed on ropes made of stainless steel type 316 in mooring systems of floating platforms in shallow tropical ocean water and doubts about the material quality came up. Routine investigations could confirm the type of alloy and the absence of sensitization, but the corrosion pattern was found unusual: individual wires of the ropes were found as hollow tubes many centimeters in length, which we refer to as hollow wire corrosion (HWC). Comparative investigations with a rope of the same specification from an arbitrarily chosen alternative producer revealed very similar susceptibility to chloride‐induced pitting but a significant difference in repassivation behavior of the two products. An electrochemical test was designed which could reproduce HWC under realistic conditions with one product while the other repassivated readily. By electron backscattered diffraction, the different susceptibility to HWC could be related to the very different textures of the wire materials of the two products, resulting from different manufacturing technologies. [ABSTRACT FROM AUTHOR]

Herein, an innovative powder‐cored wire arc additive manufacturing (PC‐WAAM) process is proposed to fabricate γ‐TiAl thin‐walled intermetallic alloy. The metallography, phase composition, and mechanical properties at different thin‐wall locations are characterized. The results show that the alternatively distributed layer‐like microstructure composed of α2 (Ti3Al) and γ (TiAl) phases is obtained along the building direction. The content of α2 phase exhibits the tendency of decreasing from the bottom to top region. This unique microstructure characteristic is closely related to the typical thermal cycling history during deposition. Moreover, the tensile strength and microhardness of the top region are lower than the middle and bottom region. In general, the current PC‐WAAM technique shows promising capability of fabricating γ‐TiAl intermetallic alloy with low cost. This work becomes a valuable reference for understanding the evolution mechanism of microstructure and paves the way for the flexible and customized additive manufacturing of γ‐TiAl alloy. [ABSTRACT FROM AUTHOR]

A structure with rocking mechanism is able to prolong the period of vibration and reduce seismic internal force. Recent research demonstrated the effectiveness of a tendon made of superelastic material wire connected in series with steel wire in controlling the amount of rotation and providing a source of hysteretic energy dissipation, thereby lowering the risk of overturning to a rigid structure undergoing whole‐body rotation. This article proposed to extend the use of superelastic tendon restraint on a (flexible) shear frame to strike a balance between the need to reduce the seismic force demand and the need to exercise control of the overturning risk. Initially, an analytical model for the rocking response of shear frame with the superelastic tendon restraint was developed. In addition, a physical model of the shear frame with tendon restraint was fabricated and tested under base excitations. Analysis results showed to match with experiment on both strain gauge and rotation sensor readings in the dynamic testing. Simulations and tests were also applied to an unrestrained shear frame for comparison. It was also found that the total deflection of the shear frame during the rocking phase could be described as horizontal vibration about a non‐constant balancing deflection. The analytical models developed for flexible rocking systems were extended in the current study to deal with superelastic tendon restrained rocking shear frames. The validity and versatility were confirmed by shaker table test results. [ABSTRACT FROM AUTHOR]

Gas‐liquid‐solid triple‐phase interfaces (TPI) are essential for promoting electrochemical CO2 reduction, but it remains challenging to maximize their efficiency while integrating other desirable properties conducive to electrocatalysis. Herein, we report the elaborate design and fabrication of a superhydrophobic, conductive, and hierarchical wire membrane in which core–shell CuO nanospheres, carbon nanotubes (CNT), and polytetrafluoroethylene (PTFE) are integrated into a wire structure (designated as CuO/F/C(w); F, PTFE; C, CNT; w, wire) to maximize their respective functions. The realized architecture allows almost all CuO nanospheres to be exposed with effective TPI and good contact to conductive CNT, thus increasing the local CO2 concentration on the CuO surface and enabling fast electron/mass transfer. As a result, the CuO/F/C(w) membrane attains a Faradaic efficiency of 56.8 % and a partial current density of 68.9 mA cm−2 for multicarbon products at −1.4 V (versus the reversible hydrogen electrode) in the H‐type cell, far exceeding 10.1 % and 13.4 mA cm−2 for bare CuO. [ABSTRACT FROM AUTHOR]

3DWelding – additive fabrication of structural steel elements This paper investigates the possibilities of robotic 3D printing with steel (WAAM – Wire and Arc Additive Manufacturing) in the construction industry. The aim of the project team is to develop a stable and economical manufacturing process for customized steel elements. Thus, the influence of different process parameters such as wire feed rate and travel speed on the weld shape and build‐up rate as well as on the material properties will be explained and a parameter window with stable, verified parameter sets will be defined for each material used. Three different filler metals (G 2Si1, G 3Si1, G 4Si1) are tested in terms of their strength and stiffness, with particular attention paid to the joining area between substrate and welded structure. For this purpose, test methods for testing additively manufactured components, especially for shear capacity, have been newly developed. As a proof of concept, an exemplary application is shown and the load‐bearing capacity of this connection is investigated in different configurations. [ABSTRACT FROM AUTHOR]

Litz wires operating in a cryogenic environment can potentially improve both the efficiency and power density of electrical machines and passive components. However, due to the low resistivity and high magnetic fields, eddy‐current losses may become significant in cryogenically cooled windings, especially in airgap winding arrangements or in the case of significant slot leakage fields, unless the litz wire parameters are carefully chosen. A framework for litz wire loss performance optimization and experimental characterisation at cryogenic temperatures is provided. An optimum operating temperature for minimum loss is derived based on analytical expressions, which highlights the role of litz wire parameters, current density and external field. The proximity loss model, used to calculate the optimum operating temperature, is validated experimentally. Two test rigs with different magnetic cores were designed and built. Copper and aluminium litz wires with a strand diameter down to 0.1 mm were tested in a liquid nitrogen bath with a uniform harmonic external magnetic field up to 0.5 T peak and a frequency up to 1 kHz. Measurements show good agreement with the theoretical results and confirm that the proposed model can be confidently used during the preliminary design of cryogenic windings. [ABSTRACT FROM AUTHOR]

Two Mg–4Li–xY (x = 0.5 and 2.0 wt%) alloy wires are investigated for application in bioresorbable medical devices that experience high levels of plastic deformation. The two wires are supplied cold drawn to a diameter of 125 μm, and a series of thermal treatments are applied to maximize ductility. The ductility of the alloys is maximized soon after complete recrystallization. Prolonged annealing causes grain coarsening in the Mg–4Li–0.5Y alloy and precipitation of a Mg24Y5 phase in both alloys. Both wires are shown to achieve ≈20% elongation to failure in tension and survive high idealized bending strains (>40%). When heat treated for optimum mechanical properties for the intended application, the Mg–4Li–0.5Y alloy develops an intense transverse basal texture; however, this is shown to weaken with increased Y content in the Mg–4Li–2Y alloy wire. The increased Y content also prevents grain coarsening, indicating that the increased Y content restricts grain boundary mobility during annealing. Both alloys have relatively high ductility, meaning both are identified as promising new materials for application in bioresorbable medical devices that require to achieve and support high levels of plastic deformation during their life cycle. [ABSTRACT FROM AUTHOR]

High‐strength carbon steel wires covered with polymer layers were exposed to different test environments simulating the conditions in the annulus of flexible pipes at low CO2 pressure and flooded with seawater. The polymer layers mimicked the antiwear tapes which are placed in between the steel layers of the tensile armor of the pipes. Specimens without the polymer layer were exposed to the same test environments for comparison and allowed identifying how the presence of the polymer layer influenced the corrosion mechanism. In some of the experiments, oxygen was introduced into the gas mixture to simulate fresh seawater entering the annulus after a breach in the outer sheath. Surface analysis of the corroded specimens after removal of corrosion scales was carried out by scanning electron microscopy, optical profilometry, and confocal microscopy. The polymer layers were observed to have a considerable effect on the corrosion morphology. [ABSTRACT FROM AUTHOR]

A new chronic total occlusion (CTO) guidewire, Conquest Pro 12 Sharpened Tip (CP12ST), has a stronger penetration force than the original CP12 and a deflection effect that it does not have. The CP12ST enables us to advance into hard plaque that has not ever penetrated, which might change CTO treatment as shown in three cases. [ABSTRACT FROM AUTHOR]

Metal Additive Manufacturing (AM) allows for the fabrication of complex shapes with high added value at low costs. Indeed, as‐built structures are near net shape: they require few to no finishing operations. However, as‐built AM parts present significant roughness caused by the layer discretization. In the case of the Wire and Arc Additive Manufacturing (WAAM) process, used for large‐scale structures, the as‐built roughness is estimated to several hundreds of micrometers. For complex geometries, a complete machining of the surfaces is not necessarily possible. In this study, an experimental method is proposed, relying on thermoelastic stress analysis, to characterize the effect of as‐built WAAM surface roughness on high‐cycle fatigue properties. Using an infrared camera, multiple cracks can be detected and monitored over a large surface on rough WAAM samples under cyclic bending. The collected data constitutes valuable information for the identification of a fatigue model dedicated to as‐built WAAM structures. Highlights: Fatigue cracks on as‐built WAAM surfaces can be monitored via infrared thermography.Fatigue life of as‐built WAAM samples is dominated by a crack propagation phase.The link between surface stress concentration and crack initiation is nondeterministic. [ABSTRACT FROM AUTHOR]

In this paper, the effects of Maxwell nanoliquid transmission with MWCNT nanotube are investigated over two circular wires with opposite currents and a stretching sheet. The innovation of this paper is the examination of MWCNT nanotube temperature and nanofluid velocity and also magnetic potential and magnetic effect in the three different places of two circular wires on the sheet. The finite element method is utilized for calculating differential equations. By increasing the distance from two wires on the stretching sheet, the amount of MWCNT nanotube temperature increased, and a large vortex forms at the bottom of the sheet. Overall, the MWCNT nanotube velocity around the two circular wires at the beginning of the sheet is 46.09% higher than the middle of the sheet and 20% higher than the end of the sheet, also the MWCNT nanotube magnetic potential around the two circular wires at the beginning of the sheet is 13.40% higher than the middle of the sheet and 23% higher than the end of the sheet. The second part of the essay relates to the using response surface methodology (RSM) method in the Design‐Expert software. Based on the results obtained from the MWCNT nanotube velocity graphs and the heat transfer cantors, and magnetism effects in the Design‐Expert software, the best optimization occurred for u = 0.07, T = 1.15, and H = 4.531. [ABSTRACT FROM AUTHOR]

Wire and arc additive manufacturing (WAAM) has the potential to significantly reduce material waste due to the milling of components made of TiAl6V4 (Ti‐64). To keep up with the market development, this resource‐efficient technology is becoming increasingly important to achieve climate policy goals. Therefore, this study not only focuses on the influence of different process parameters, such as torch and wire feed speed, but also different gas mixtures on the microstructure and related mechanical properties, as well as on the scalability by investigating single‐ to multilayer welded structures. The wire feed speed is found to have a major influence on the geometry and mechanical properties. The use of different process gases, i.e., argon (Ar), helium (He), and a mixture of 70% He and 30% Ar neither significantly affect the microstructure nor the mechanical properties. It is also found that a solution heat treatment followed by an annealing step degrades mechanical properties, while an ordinary stress‐relief heat treatment leads to improved mechanical properties. It is shown that by adapting WAAM process and heat treatment parameters, mechanical properties of additively produced specimens can be achieved, which are fully comparable to milled components. [ABSTRACT FROM AUTHOR]

Radiative thermal management has attracted increasing attention for the advantages of energy saving and carbon emission reduction. Infrared radiation coatings are widely adopted to alleviate the low infrared emissivity of commonly used metal alloy electrothermal materials. However, traditional infrared radiation coatings are faced with the issues of the unsteady waveband emissivity, low interfacial adhesion to substrates, and poor long‐term thermal stability. Herein, a bush‐shaped vertical graphene (BVG) grown on nichrome (Ni–Cr) wire is demonstrated, relying on which BVG/Ni–Cr wire presents a high blackbody‐like emissivity of ≈0.96 across a wide wavelength range (2.5–18 µm). When used for radiative heating, BVG/Ni–Cr wire achieves a high thermal radiation efficiency with an order of magnitude improvement compared with bare Ni–Cr wire, as well as the superior deformation and thermal stabilities. These findings reveal the impressive potentials of BVG as an excellent infrared radiation material for the energy‐efficient radiative thermal management. [ABSTRACT FROM AUTHOR]

Constructing surface wetting gradients usually involves complex physical or chemical methods. Here, a novel Gradient‐Janus wire (GJW) can be designed based on the theory of newly Liquid Confined Modification (LCM). In LCM theory, reaction difference will be generated by the confinement of reaction solution, which constructs wettability discrepancy on the same curve surface. Thus a unique continuous Gradient‐Janus wetting region can be constructed in a long range on a 1D wire. It is demonstrated that GJW can propel water droplets to transport the distance of ≈73 mm in 0.9 s, and liquid bridge to 85 mm (the longest among this kind of study) in 0.79 s with peak velocity high up to 237 mm s−1 (over 20 times faster than droplet transport on surface of Sarracenia trichome). The mechanism is attributed to cooperation between imbalanced Laplace pressure and surface tension force to generate the driving force act on droplet, liquid bridge, or column transport, respectively. LCM directs the large‐scale facile fabrication of GJWs within 20 s. A large‐scale GJW array can achieve the high‐efficient transport of water droplet in a wide volume range (few µL to 1 mL), making it potential in fogwater harvesting. [ABSTRACT FROM AUTHOR]

Wire breakage has always attracted much attention in drawing. Mastering the mechanism of drawing fracture can effectively improve the quality of steel wire. In this study, the morphology of the fracture samples is analyzed. There are obvious V‐shaped microcracks in the materials by observing the microstructure. Base on the above results, the wire models with V‐shaped microcrack of different inclinations are established via the finite element method (FEM). Besides, the multi‐pass drawing under different back tension is simulated, and the process from crack propagation caused by damage to fracture is realized. The results show that microcrack has a great influence on the drawing fracture, and inclination is a key factor. With the increase of angle, the propagation rate of crack increases accordingly. Meanwhile, back tension will increase the accumulation of damage. The larger the back tension is, the larger the crack path is, which eventually leads to the formation of pen‐tip shaped fracture. Highlights: Steel wire with central V‐shaped microcrack is more likely to occur pen‐tip fracture.The growth rate of crack increases as the angle of V‐shaped microcrack increases.The action of back tension will make the drawing fracture occur earlier.Microcrack and back tension should be avoided, to reduce the risk of drawing fracture. [ABSTRACT FROM AUTHOR]

Summary: This paper presents an experimental investigation of alumina trihydrate (ATH) in glass fibre reinforced polymers (GFRP), aiming to determine the influence of ATH concentration on improved flame‐retardant properties. For this research, different concentrations of ATH: 37 phr (parts per hundred resin), 40, 47.5, 50 and 55 phr, were added in isophthalic polyester matrix composites reinforced with E‐glass fibre through a pultrusion process. These composites were tested for flammability and flame propagation using the mass loss calorimeter cone (MLCC), limiting oxygen index (LOI) and glow wire tests. Simultaneous thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) was performed to evaluate the thermal stability and enthalpy. These analyses assessed the effectiveness and influence of each ATH concentration. It was observed in the MLCC tests that the ATH concentration of 40 phr reduced the peak heat release rate (PHRR) by 27% compared to a composite with 37 phr. All specimens showed the desired commercial result for wires and cables in the glow wire test since the composites reached the maximum glow wire flammability index (GWFI) of 960 °C and a glow wire ignition temperature (GWIT) above 900 °C. Thus, the addition of ATH above 40 phr leads to an improvement in the flame‐retardant properties of glass fibre reinforced polymers. [ABSTRACT FROM AUTHOR]