Composite Wires Research Articles

Investigating the impact of Nano Cu at different weight percentages on the electrical conductivity of aluminum wire

This research focuses on effects of three different nano cu on Aluminum wire to study the electrical conductivity pattern in those composite wires. The need for enhancing the electrical conductivity of materials has led to innovative approaches such as the incorporation of nanoscience into metal matrices. In this study, the effects of nano copper (Cu) at three different weight percentages (1%, 2%, and 3%) on the electrical conductivity of aluminum wire were studied carefully. Nano cu had an average of 150 nanometer nm length with 99.8 purity. Understanding these effects is crucial for advancing the development of high-performance conductive materials for various applications, including electronics and power transmission.

Properties of Wedge Wire Bonded Connection Between a Composite Copper Core Aluminum Shell Wire and an 18650 Cylindrical Lithium-Ion Battery Cell

Wedge wire bonding is a solid-state joining process that uses ultrasonic vibrations in combination with compression of the materials to establish an electrical connection. In the battery industry, this process is used to interconnect cylindrical battery cells due to its ease of implementation, high flexibility and ease of automation. Wire materials typically used in battery pack manufacturing are pure or alloyed aluminum and copper. While copper wires possess better electrical properties, the force used in the bonding process can lead to cell isolator damage and cell thermal runaway. This is an unacceptable result of the bonding process and has led to the development of new types of composite wires containing a copper core embedded in an aluminum shell. This material has the advantage of high copper electrical and thermal conductivity combined with less aggressive bonding parameters of the aluminum wire. The aim of this study was to establish a process window for the wedge wire bonding of 400 µm composite copper–aluminum Heraeus CucorAl Plus wire on the surface of a BAK 18650 battery cell. This study was conducted using a Hesse Bondjet BJ985 CNC wire bonder fitted with an RBK03 bond head designed for the bonding of copper wires. The methods used in this study included light and scanning electron microscopy of bond and battery cell cross-sections, shear testing on the XYZtec Sigma bond tester system, and energy dispersive spectroscopy. The results were compared with a previous study conducted using a wire of the same diameter and made out of high-purity aluminum.

Dual effects of pre-deformation and shape recovery process on martensitic transformation behavior in NiTi-Nb composite wire

The martensitic transformation behavior of NiTi-Nb composite wire following the pre-deformation and shape recovery (PD&SR) process was investigated. The wire drawing process significantly decreased the martensitic transformation start temperature (Ms) of NiTiNb alloy. Interestingly, the PD&SR process exhibited dual effects on the initial Ms temperature, depending on the annealing temperature. When the composite wire was annealed at higher temperature, the PD&SR process decreased the Ms temperature. In contrast, when the composite wire was annealed at lower temperature, the PD&SR process raised the Ms temperature. These dual effects can be attributed to the competition between the hindering effect of deformation dislocation and the promoting effect of stress coupling near the interface between the β-Nb phase and the NiTi matrix. At lower annealing temperature, the stress coupling generated by the β-Nb nanowires and the NiTi matrix is stronger, leading to an increase in the Ms temperature. Furthermore, the pre-deformation strain and shape recovery temperature influenced the dislocation density and the strength of stress coupling, thereby regulating the Ms temperature within a certain range.

Unveiling the mechanical and microstructural properties of SiC reinforced aluminum wires recycled from scraps by friction stir extrusion

Friction Stir Extrusion (FSE) has been proven as an effective solid-state process to directly recycle metal chips into high-quality wires/rods/tubes. However, the demand for Al-based composite wires with enhanced properties is substantial, and achieving a uniform distribution of the strengthening phase within the composite wire by establishing a robust metal/ceramic interface remains a significant challenge. In this study, AA6082 Aluminum alloy wires reinforced with 12.5 vol% SiC particles, exhibiting homogeneous particle distribution and superior mechanical properties, were successfully produced through the FSE technique. The investigation focused on examining the influence of processing parameters and the addition of SiC reinforcement on the microstructure and mechanical characteristics of the extruded wires. Scanning electron microscopy (SEM), Electron Backscatter Diffraction (EBSD), together with microhardness, bending, and tensile tests, were used to comprehensively analyze the resulting properties. The findings demonstrate a substantial enhancement in the wires' mechanical properties due to the SiC particles. Both tool rotation and tool force were varied during the experimental campaign. Notably, the reduction in porosity and grain refinement resulted in a 12.78 % increase in tensile strength and an 18.6 % improvement in microhardness compared to Al 6082 alloy extruded wires. Grain orientation analysis revealed a fully recrystallized microstructure with a weak texture. Furthermore, the study evaluated power consumption and surface roughness while assessing the feasibility of deposition, thereby highlighting the potential application of this technique in advanced additive manufacturing processes.

Cu-stabilized 7-filament MgB2 wires by an internal Mg diffusion process

Compared with the Powder-In-Tube (PIT) method, MgB2 wires fabricated through the Internal Mg Diffusion (IMD) method demonstrate superior superconducting properties. However, magnesium’s hexagonal close-packed (HCP) crystal structure presents challenges in introducing Cu stabilizers into wires, thereby constraining the thermal stability of MgB2 wires. In this investigation, we improved the fabrication process to produce four distinct hundred-meter-scale Cu-stabilized 7-filament MgB2 wires. Experimental results indicate that the composite wires’ maximum Cu/SC Ratio reaches 2.45. Introducing Cu stabilizers enables the wire to achieve a tensile strength of 393 MPa at room temperature. Furthermore, the critical current density Jc of the wire can reach 2.3 × 105 A/cm2 at 4.2 K and 4 T. Our research provides a reliable reference for further preparation of high-stability MgB2 wires.

Numerical modelling and measurement of the E-I characteristics of MgB2 wire in sub-cooled water ice

This work presents a comprehensive 3D numerical model of MgB2 multi-filamentary superconducting wires using the Finite Element Method (FEM) software, COMSOL Multiphysics® 6.0. The study aims to investigate the electro-thermal behavior of MgB2 composite wires during standard transport measurements at various initial temperatures under subcooled water ice conditions. By solving a series of partial differential equations governing heat transfer and dynamic current transport, the model provides detailed insights into the wire’s performance. The simulation results are rigorously compared with experimental E-I characteristics measured for 6-filament MgB2 wires with internal copper stabilization. This comparison validates the model and highlights its capability to predict the behavior of superconducting wires under cryogenic conditions. The findings offer valuable data on the current distribution, ohmic losses, and overall thermal stability of the composite wires, contributing to the advancement of cryogen-free superconducting technologies. This study bridges the gap in the literature regarding the electrothermal dynamics of MgB2 wires cooled by subcooled water ice, providing a foundation for further research and practical applications in high-field generation devices.

Exploration microstructural evolution and wear mechanisms of wire arc additive manufacturing NiTi/Nb bionic composite materials

NiTi/Nb layered heterogeneous structure (LHS) materials with different layer spacings were designed and fabricated using composite wire arc additive manufacturing. The NiTi/Nb LHS samples consisted of NiTi phase and β-Nb phase, and no other intermetallic compounds were formed. The NiTi layer in the NiTi/Nb LHS sample changes from a homogeneous eutectic microstructure to a gradient heterogeneous eutectic microstructure as the layer thickness increases. The Nb layer grains are much smaller than the NiTi layer grains, and no obvious texture is formed in the NiTi/Nb LHS samples. NiTi/Nb LHS samples still have a certain recoverable strain at room temperature, with a maximum recoverable strain of 4.36 % after 10 cycles of 10 % strain compression. The wear rate of the NiTi layer of the NiTi/Nb LHS samples was lower than that of the Nb layer. The main wear mechanisms on the Nb surface are abrasive wear, adhesive and oxidative wear while the main wear mechanism on the NiTi surface is adhesive wear. When the layer thickness ratio of NiTi layer to Nb layer is 2:1, the NiTi/Nb LHS samples form a gradient heterogeneous eutectic structure in the NiTi region, which in turn enhances the wear resistance of the LHS samples. In this study, cross-scale NiTi alloy and Nb heterogeneous components were constructed by wire arc additive manufacturing, which showed good wear resistance. The design provides a new solution for integrated additive manufacturing repair of heterogeneous metals in engineering applications.

Investigations on the Effects of Bonding and Forming Conditions on the Deformation Behavior of Copper-Steel Bimetallic Rods during the Cold Drawing Processes.

Metal composite parts are widely used in different industries owing to their significant improvement in material properties, such as mechanical strength, electrical conductivity, and corrosion resistivity, compared to traditional single metals. Such composite parts can be manufactured and processed in different ways to achieve the desired geometry and quality. Among various metal forming techniques, drawing is the most commonly used process to produce long composite wires or rods from raw single materials. During the drawing process of composite wires or rods, not only does the core radius ratio change, but the core or sleeve layer may also undergo necking or fracture due to excessive tensile stresses in the softer layer. In this paper, bimetallic rods with AISI-1006 low-carbon steel cores and C10100 oxygen-free electronic copper sleeves are modeled using the finite element software DEFORM. The simulation models are verified by drawing experiments. The effects of initial bonding conditions, the initial core ratio, reduction ratio, semi-die angle, drawing speed, and friction on the plastic deformation behavior of the bimetallic rods are investigated. The results indicate that the initial bonding conditions have a great impact on the deformation behavior of the billets in terms of strain distribution, material flow, residual stress, and the final core ratio. The permissible forming parameters for obtaining a sound product are investigated as well. With the aid of these analyses, the drawing process and the quality of the products can be controlled steadily.

Study on the microwave absorption properties of FeCoNiCrMn/PLA 3D printed composites

The work in this paper is dedicated to the study of wave-absorbing materials for applications in extremely harsh environmental conditions such as seawater and oil. In this paper, FeNiCrMn high-entropy alloy material with corrosion resistance and polylactic acid (PLA) material with high strength and high modulus were used to prepare more environmentally adaptable FeNiCrMn/PLA electromagnetic(EM) microwave-absorbing materials by two-step method of ball milling and melt extrusion.The physical phases, microscopic morphology, EM parameters and mechanical performance of FeCoNiCrMn/PLA composites were characterized using XRD, SEM, Vector Network Analyzer and Universal Testing Machine respectively. The microwave-absorbing properties of FeCoNiCrMn/PLA composites were investigated, and the effects of their components and micro-morphology on the microwave-absorbing and mechanical performance were discussed. The results show that when the FeCoNiCrMn content reaches 25 wt% and the thickness is 4.5 mm, the minimum reflection loss of FeCoNiCrMn/PLA composites reaches −24.58 dB, and the effective microwave-absorbing bandwidth is 2.51 Ghz. The maximum tensile strength and elongation at break of the composites could reach 23.83 MPa and 7.12 %, respectively. The microwave-absorbing ability of FeCoNiCrMn composites is mainly due to their rich EM loss mechanisms, including dielectric losses such as dipole polarization, interface polarization, defect-induced polarization, etc., as well as magnetic losses such as natural resonance, exchange resonance, and eddy current losses. Finally, the wide-angle microwave-absorbing characteristics of FeCoNiCrMn/PLA 3D-printed composites were investigated, the results showed that the composites with FeCoNiCrMn content of 25 wt% had Radar Cross Section (RCS) values lower than −10 dBm² within the microwave incidence angle of −90° < θ < −6° and 6° < θ < 90°, which indicated that the composites had wide-angle microwave-absorbing capability. The materials have microwave-absorbing properties along with a certain degree of mechanical strength, and at the same time have good environmental adaptability. The FeCoNiCrMn/PLA composite wire can be used in FDM technology to prepare structural microwave absorbers, realizing the integration of “material-design-manufacturing”, which has a broad application prospect in the field of EM microwave absorption and 3D printing.

Integrating High-Performance Flexible Wires with Strain Sensors for Wearable Human Motion Detection.

Flexible electronics have revolutionized the field by overcoming the rigid limitations of traditional devices, offering superior flexibility and adaptability. Conductive ink performance is crucial, directly impacting the stability of flexible electronics. While metal filler-based inks exhibit excellent conductivity, they often lack mechanical stability. To address this challenge, we present a novel conductive ink utilizing a ternary composite filler system: liquid metal and two micron-sized silver morphologies (particles and flakes). We systematically investigated the influence of filler type, mass ratio, and sintering process parameters on the composite ink's conductivity and mechanical stability. Our results demonstrate that flexible wires fabricated with the liquid metal/micron silver particle/micron silver flake composite filler exhibit remarkable conductivity and exceptional bending stability. Interestingly, increasing the liquid metal content results in a trade-off, compromising conductivity while enhancing mechanical performance. After enduring 5000 bending cycles, the resistance change in wires formulated with a 4:1 mass ratio of micron silver particles to flakes is only half that of wires with a 1:1 ratio. This study further investigates the mechanism governing resistance variations during flexible wire bending. Additionally, we observed a positive correlation between sintering temperature and pressure with the conductivity of flexible wires. The significance of the sintering parameters on conductivity follows a descending order: sintering temperature, sintering pressure, and sintering time. Finally, we demonstrate the practical application of this technology by integrating the composite ink-based flexible wires with conductive polymer-based strain sensors. This combination successfully achieved the detection of human movements, including finger and wrist bending.

Study of the structure of filler composite wire for surfacing wear-resistant layers

Study of the structure of filler composite wire for surfacing wear-resistant layers

Thermo-Chemo-Mechanical Modeling of Residual Stress in Unidirectional Carbon Fiber-Reinforced Polymers during Manufacture.

The application of carbon fiber-reinforced composite materials in marine engineering is growing steadily. The mechanical properties of unbonded flexible risers using composite tensile armor wire are highly valued. However, the curing process generates a certain amount of internal residual stress. We present a detailed analysis of epoxy resin laminates to assess the impact of thermal, chemical, and mechanical effects on the curing stress and strain. An empirical model that correlates temperature and degree of cure was developed to precisely fit the elastic modulus data of the curing resin. The chemical kinetics of the epoxy resin system was characterized using differential scanning calorimetry (DSC), while the tensile relaxation modulus was determined through a dynamic mechanical analysis. The viscoelastic model was calibrated using the elastic modulus data of the cured resin combining temperature and degree of the curing (thermochemical kinetics) responses. Based on the principle of time-temperature superposition, the displacement factor and relaxation behavior of the material were also accurately captured by employing the same principle of time-temperature superposition. Utilizing the empirical model for degree of cure and modulus, we predicted micro-curing-induced strains in cured composite materials, which were then validated with experimental observations.

Magnetic anisotropy of NiFeP/Cu composite wire induced by chemical plating under DC current

NiFeP/Cu composite wires were fabricated by chemical plating under DC current. In this work, DC current was adjusted from 0 to 100 mA and the influence of current on the surface morphology, magnetic properties and GMI effect was investigated. It is found that the DC current has little impact on the composition of the coating. However, with the change of current, the surface morphology, plating rate and magnetic properties of the coating have undergone significant changes which in turn affect the GMI effect. As a result, when the appropriate current is applied, a transverse magnetic structure with an anisotropy angle of approximately 26 degrees can be generated, enabling a maximum GMI ratio of 1964 % and a field sensitivity of 463 %/Oe, which shows potential practical application in the magnetic sensors.

High precision three-dimensional ellipse fitting correction for galloping monitoring

In this paper, we propose and demonstrate a high precision three-dimensional (3D) ellipse fitting correction method for optical fiber composite overhead ground wire (OPGW) galloping monitoring, based on weak fiber Bragg grating array. 3D ellipse formed by three outputs of the system is fitted by the coordinate rotation and least square methods, and direct current (DC) components and alternate current (AC) component coefficients of the three outputs are obtained. By differentiating and cross-multiplying the three outputs, those DC components are zeroized, AC component coefficients are normalized, and finally, the interference phase signal is calculated. The experimental results show that the proposed method can demodulate the vibration signals better, and the fitted R2 is above 0.99. The system is implemented on a 220 kV transmission line in the plateau region of Western China, forecasting a galloping period with a wavelength of about 60 m within the span accurately. This method demonstrates suitability for monitoring OPGW transmission line galloping events.

Electrical and mechanical limits of ex situ MgB2 wires for cabling

One of the objectives of the SCARLET project is to develop and industrially manufacture superconducting MgB2 cables cooled by liquid hydrogen. The ex situ powder-in-tube MgB2 wires manufactured by ASG are considered for the cable design that can carry DC current of 20 kA. These braided superconducting wires, containing brittle filaments, require high current. Thus, the study of the electro-mechanical properties of MgB2 wires is crucial for the cable design and its functional use. Superconducting wires have to withstand all the stresses applied during the cabling process, installation, and operations at the temperature of around 20 K. Hence, several configurations of MgB2/Ni/Monel composite wires have been subjected to detailed electrical and mechanical characterizations, which allow the estimation of the stress limits during the manufacturing of the designed cable. These experiments demonstrated that the maximal tensile stress applied to the wire at room temperature should be below 180–200 MPa, and safety bending observed for the outer filament strains was below 0.3%–0.35%. It is also revealed that the limit of acceptable torsion (expressed by the twist pitch to wire diameter L t/d w) is affected by the filament architecture and wire diameter. This limit should be above 100 for 1 mm wire and above 150 for 1.53 mm wire.

Design strategy to simultaneously enhance electrical conductivity and strength: Cold-drawn copper-based composite wire with in-situ graphene

We proposed a unique wire-production process by rolling up and drawing chemical vapor deposition copper/graphene (Cu/Gr) foils, and a good strength-conductivity trade-off was achieved originating from the dispersed Gr in Cu matrix and the high-quality heterointerfaces. The 1.14 mm cold-drawn composite wire exhibited a tensile strength of 455 ± 5 MPa and a conductivity of 98.18 ± 0.16 % of the International Annealed Copper Standard (IACS), and the tensile strength was 250 ± 2 MPa with a satisfied electrical conductivity of 101.68 ± 0.52 % IACS upon annealing. The microstructure involution during the preparing process was revealed, and the reinforcement mechanisms in the yield strength and conductivity due to the introduced Gr were clarified. The results indicated that the Gr plays a role in pinning dislocations and preventing grain boundary movement during deformation and the subsequent annealing, thereby enhancing the strength of the Cu matrix. Meanwhile, the Cu-Gr coupling interfaces exhibited an electronic doping effect, enhancing the conductive properties. Our work presented a feasible method for preparing Cu/Gr composite wire with comprehensive electrical conductivity and strength optimization.

Combination Treatment of Splinting with Wire Composite and Artificial Tooth Pontic for Improved Aesthetics: A Case Report

Advanced bone loss in patients with periodontitis often leads to increased tooth mobility, sometimes resulting in tooth loss. The mobility of teeth necessitates splinting to optimize periodontal treatment outcomes in terms of aesthetics and periodontal health. This case report presents a novel approach using an artificial tooth pontic as a periodontal splint, utilizing wire stabilization to prevent severe tooth mobility and enhance esthetics. A 37-year-old male with aggressive periodontitis (Stage III, Grade C) exhibited extensive periodontal destruction, particularly in the upper and lower anterior regions. Pathological migration was evident following the loss of teeth 31 and 41, with additional anterior teeth in the lower jaw showing mobility and trauma from occlusion, notably tooth 33. The patient underwent nonsurgical periodontal therapy, including scaling, subgingival debridement, occlusal adjustment, and splinting. Stabilization was achieved by applying a wire splint from teeth 34 to 43, incorporating an artificial tooth pontic. Subsequent evaluations revealed improvements in clinical parameters such as probing pocket depth, tooth mobility, and bleeding on probing during supportive periodontal therapy visits. The splint remained stable, and the patient expressed satisfaction with their appearance remaining unaffected. This case demonstrates that severe tooth mobility can be effectively stabilized using a composite wire splint and an artificial tooth pontic, enhancing the patient's esthetic outcomes.

Application of magnetic flux leakage method in the crimping inspection of carbon fiber conductor

Compared with steel core aluminum strand wire, carbon fiber composite core wire has many excellent characteristics such as large flow capacity, good heat resistance, light weight, but its mechanical properties are poor, and the unqualified crimping quality is easy to lead to wire breakage accidents, which greatly affects its popularization. For this reason, a scheme for the detection of crimping defects of carbon fiber composite mandrel based on magnetic leakage method is proposed. Firstly, the finite element analysis model of the clamping fixture was established, and then the magnetic pole distance k and radial air gap n of the magnetic leakage testing device were explored. Based on the signal-to-noise ratio under the two typical defect conditions of fracture and low pressure, the most suitable excitation structure parameters of the magnetic leakage device were obtained. The results show that when k=55mm and n=3.5mm, the signal-to-noise ratio of MFL detection device reaches the best effect. The research results are of great significance to the quality inspection of compacts of carbon fiber composite mandrel.

Effect of extrusion speed on properties of Cu−5vol.%Ti2SnC composite wire fabricated by friction stir back extrusion process

The effect of axial traverse speed of friction stir back extrusion (FSBE) process on the microstructure, mechanical, electrical, and wear properties of Cu−Ti2SnC composite wire was investigated. The FSBE process was performed on the primary composite made by the powder metallurgy method with 5 vol.% of Ti2SnC MAX phase. The results showed that as the extrusion speed increased, the twins formed in the microstructure increased, the Ti2SnC particles became finer, and the interface of bonding of the MAX phase−Cu matrix improved. The Cu−Ti2SnC composite wire fabricated at the rotational speed of 600 r/min and axial traverse speed of 25 mm/min showed the maximum hardness, yield strength, and ultimate tensile strength of HV 132.7, 278.34 MPa, and 485.15 MPa, respectively. This finding was due to its strong interfacial bonding and fine MAX phase particles. Besides, the larger grain size, the better interface bonding, and the lower the porosity resulted in the highest electrical conductivity of 89.21% (IACS) and least wear rate of 0.0015 mg/m of Cu−Ti2SnC composite wire fabricated at rotational speed of 600 r/min and axial traverse speed of 25 mm/min.

Experimental study on RC beams shear‐strengthened with composite polymer mortar and steel strands wire mesh

AbstractThis paper presents an experimental investigation of the use of composite polymer mortar (CPM) and steel strands wire mesh (SSWM) to strengthen reinforced concrete (RC) beams in shear. In order to maximize the shear resistance of the steel strands, a new type of anchor device called wedge‐shaped steel plate hoops (WSSPHs) was developed. And the study aimed to examine the effect of shear‐to‐span ratio and prestressing level on the mechanical properties of the beams. A total of nine beams were constructed and tested under four‐point bending monotonic load, comprising three control beams and six strengthened beams. The study analyzed the damage modes, load‐deflection curves, strength, stiffness, and ductility of the beams. The test results indicated that (1) the mechanical properties of the strengthened beams were improved, with the shear capacity improving by 38.47%–71.37% after strengthening. (2) It was observed that SSWM could be utilized more effectively in high shear‐to‐span ratio beams among the strengthened beams with the same prestressing level. (3) Additionally, the larger prestressing level was found to change the design damage mode of the test beams, with RB‐2.5‐0.5 failing in bending. Finally, a model was proposed to predict the shear capacity of the test beams based on the specification GB 50011‐2010. The model considered the effect of the initial prestressing of the steel strands.