Composite Wires Research Articles

Fabrication of new gradient AZ91-bioactive glass composite using friction stir back extrusion

This study investigated the microstructure, mechanical characteristics, and in vitro corrosion behavior of gradient AZ91-bioactive glass composite wire fabricated by friction stir back extrusion. The results showed that by decreasing the extrusion speed from 40 to 20 mm/min, the distribution factor of bioactive glass increased from 0.31 ± 0.04–0.45 ± 0.07, and more homogenous grain size was formed at the surface and center zone of the composite wire. Under the influence of heat and plastic deformation during friction stir back extrusion, despite the formation of the β-phase in separate islands, the α + β eutectic phase was also formed in the composite wire. In composite wire processed with a rotational speed of 800 rpm and extrusion speed of 20 mm/min, a gradient distribution of bioactive glass was formed in the cross section of the wire. Compared to an as-cast AZ91 alloy, friction stir back extrusion conducted at a rotational speed of 800 rpm and an extrusion speed of 20 mm/min resulted in a 44% increase in corrosion resistance in simulated body fluid (SBF).

Magnetocaloric properties of a wire composite of La (Fe,Mn,Si)13-H alloy powders in a Gd cylindrical tube

The enhancement of magnetocaloric effect (MCE) and the extension of effective magnetic refrigeration temperature region near room temperature are critical requirements for highly efficient and environment friendly cooling technologies. The large isothermal entropy change of the first-order phase transition material and broader temperature range of the second-order phase transition material are combined into the composite form of La(Fe,Mn,Si)13-H and Gd with their transition temperatures close to room temperature. In this work, wire composites were fabricated using the La (Fe,Mn,Si)13-H powders filled inside the Gd tube. The magnetocaloric properties of the wire composite are convoluted from individual constituents. The dual transitions temperature were observed at 287 K and 292 K. The isothermal entropy change response of the wire composite can be obtained by using the simulation with the combined weight of the Gd tube and La (Fe,Mn,Si)13-H powders. The maximum isothermal entropy change (−ΔSiso) at μoH= 5 T calculated from isothermal magnetization measurements are 8.7 for Gd tube, 16.9 for La(Fe,Mn,Si)13-H powders, and 10.2 J/kg•K for a wire composite. The magnetocaloric properties including the order of phase transition of the wire composite are close to second-order type due to the higher weight fraction of Gd tube.

Magneto-Impedance Tomography of Composite CuBe/FeCoNi Wires

The results of investigation of the distribution of electrical and magnetic properties over the cross-section are presented for Cu[Formula: see text]Be2/Fe[Formula: see text]Co6Ni[Formula: see text] composite wire of the “highly conductive core-magnetically soft coating” type, obtained by electrolytic deposition of the FeCoNi layer. Studies performed by the magneto-impedance tomography (MIT) made it possible to determine the specific electrical conductivity of the materials of the core and coating. It was established that the electrodeposited coating had a magnetic structure that was inhomogeneous over the thickness.

Microstructures and properties of copper matrix composite wires reinforced with Ti2SnC particles

ABSTRACT This study investigates the fabrication of copper matrix composite reinforced with 8 wt-% of the Ti2SnC phase using friction stir-back extrusion. It explores the effect of rotational speed on the microstructure and properties of Cu–Ti2SnC wire composites. The results showed that the grain size of the composite increased from 3.5 ± 0.6 to 5.7 ± 0.5 µm as the rotation speed increased from 400 to 1000 rev min−1. With the addition of the Ti2SnC phase, the yield and ultimate tensile strength increased by 178% and 33%, respectively. In addition, although the electrical conductivity decreased by 25% by adding 8 wt-% of reinforcement, the electric conductivity of composite wire increased by 19% with the increase of the rotation speed from 400 to 1000 rev min−1.

Analysis of Microstructure and Properties in Cold Rotary Swaged Copper-Clad Magnesium Wires

The copper-clad magnesium composite wire with a diameter of 3.12 mm and good interface bonding was prepared by cold rotary swaging. The effects of cold rotary swaging and annealing temperature on microstructure and properties of the wire were studied by electron backscatter diffraction, transmission electron microscopy, as well as mechanical and electrical properties tests. The results show that the multi-pass cold rotary swaging composite has a great effect on grain refinement, microstructure recovery and structural unit reorientation, and can also make the wire obtain good interfacial bonding quality, improve mechanical properties, and the tensile strength can reach 289 MPa. The width of the interface layer widened with the increase of temperature, and the increase improved significantly at annealing temperatures of 450 °C and 500 °C, and the intermetallic compounds Mg2Cu and MgCu2 were found in the longitudinal section of the wire, respectively. After a reasonable annealing process of 400 °C/1 h, the interface layer did not thicken significantly, and the ductility and conductivity of the wire were the best, and the elongation after fracture and conductivity could reach 17% and 81.1% IACS, which increased by 15.2% and 3.8% compared with before annealing, respectively.

OPGW positioning and early warning method based on a Brillouin distributed optical fiber sensor and machine learning.

A method of optical fiber composite overhead ground wire (OPGW) positioning based on a Brillouin distributed optical fiber sensor and machine learning is proposed. A distributed Brillouin optical time-domain reflectometry (BOTDR) and Brillouin optical time-domain analyzer (BOTDA) are designed, where the ranges of BOTDR and the BOTDA are 110km and 125km, respectively. An unsupervised machine learning method density-based spatial clustering of applications with noise (DBSCAN) is proposed to automatically identify the splicing point based on the Brillouin frequency shift (BFS) difference of adjacent sections. An adaptive parameter selection method based on k-distance is adapted to overcome the parameter sensitivity. The validity of the proposed DBSCAN algorithm is greater than 96%, which is evaluated by three commonly external validation indices with five typical BFS curves. According to the clustering results of different fiber cores and the tower schedule of the OPGW, the connecting towers are distinguished, which is proved as a 100% recognition rate. According to the identification results of different fiber cores of both the OPGW cables and tower schedule, the connecting towers can be distinguished, and the distributed strain information is extracted directly from the BFS to strain. The abnormal region is positioned and warned according to the distributed strain measurements. The method proposed herein significantly improves the efficiency of fault positioning and early warning, which means a higher operational reliability of the OPGW cables.

Effects of Ti2SnC MAX phase reinforcement content on the properties of copper matrix composite produced by friction stir back extrusion process

In this present work, the effect of Ti2SnC content on the microstructure, mechanical, electrical and wear properties of friction stir back extrusion (FSBE) processed Cu–Ti2SnC composite wire was investigated. The FSBE process was performed on copper matrix composite with 0–30 vol% of Ti2SnC reinforcement. The results show that by increasing the content of the Ti2SnC phase the hardness of the composite increased and reached 280.51 HV for composite containing 30 vol% Ti2SnC phases. The proper interface bonding was obtained in the composite containing 1 and 5 vol% Ti2SnC phases. The highest yield strength, ultimate tensile strength and wear resistance were obtained in the composite containing 5 vol% Ti2SnC phases due to the proper interface bonding. Also, the highest electrical conductivity (95.67% IASC) was obtained in a composite containing 1 vol% Ti2SnC phases. By increasing Ti2SnC phases higher than 5 vol% discontinuities between the Ti2SnC phase particles and the Cu matrix increased and result in decreasing strength and electrical conductivity of copper matrix composite.

Effect of Annealing on the Interface and Properties of Pd/Al Composite Wires

This paper investigates the changes in the interface organization and properties of 0.10 mm Pd/Al composite wires annealed at different temperatures. The optimum comprehensive performance of the material was obtained after annealing at 300 °C for 120 s. Its tensile strength, conductivity and elongation are 140.61 MPa, 46.82%IACS and 14.89%, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to observe the intermetallic compounds on the interface. The annealing temperature and the formation heat of intermetallic compounds determine the categories and evolution of intermetallic compounds. When the thickness of the intermetallic layer is more than 1 μm, it has a serious effect on the electrical conductivity and elongation of the materials.

Fast time-varying current triggering flux jumps of multi-filamentary Nb3Sn wire exposed to oblique magnetic field

Due to the oblique magnetic field and rapid time-varying current, the electromagnetic response and thermomagnetic instabilities of high-field superconducting dipole magnets are quite different from the solenoid coils. In this work, we theoretically investigate the flux jump of composite multi-filamentary Nb3Sn wire with high critical current density exposed to an oblique magnetic field and fast transport current. The thermomagnetic stability/instability regions are obtained with respect to flux creep factor and oblique ratios of magnetic field. It is found that the parallel component of the oblique magnetic field can suppress the flux jump. Unlike slow current, it is interesting to find that the fast variations of self-field by high ramp current can trigger flux jumps in Nb3Sn wire. The fast current triggering flux jumps can be tuned by the static oblique magnetic field. Furthermore, we demonstrate that current-like distribution is more likely to trigger quenches, while the magnetic field-like distribution is more likely to trigger flux jumps. The findings of this work are helpful for the optimization of the superconducting coils exposed to oblique magnetic field and fast time-varying current.

Two-Step Preparation of CCF/PEEK Wrapped Yarn for 3D Printing Composites with Enhanced Mechanical Properties.

Continuous fiber reinforced thermoplastic composites (CFTPCs) have shown advantages such as high strength, long life, corrosion resistance, and green recyclability. Three-dimensional printing of CFTPCs opened up a new strategy for the fabrication of composites with complicated structures, low cost, and short production cycles. However, a traditional 3D printing process usually causes poor impregnation of the fiber or surface damage of the fiber due to the short impregnation time or high viscosity of the thermoplastic resin. Here, continuous carbon fiber/poly(ether-ether-ketones) (CCF/PEEK) wrapped yarn was fabricated via powder impregnation and using double spinning technology for the 3D printing. The concentration of PEEK powder suspension and wire speed were optimized as 15% and 2.0 m/min. The twist of wrapped yarn was optimized as 1037 T/m. Mechanical testing showed that the 3D-printed composite wire had excellent tensile and bending strength, which was about 1.6~4.2 times larger than those without the powder pre-impregnation process. It is mainly attributed to the improved impregnation of the CF which took place during the powder pre-impregnation process. We believe that our research on wrapped yarn for 3D-printed composites provides an effective strategy for the 3D printing of composites with enhanced mechanical properties.

Effects of Ti2SnC MAX Phase on Microstructure, Mechanical, Electrical, and Wear Properties of Stir‐Extruded Copper Matrix Composite

Herein, the effect of Ti2SnC MAX phase reinforcement and friction stir back extrusion (FSBE) parameters on the microstructure, mechanical, electrical, and tribological behavior of Cu‐Ti2SnC composite is investigated. The results indicate that, depending on the rotational speed of the extrusion process, an equiaxed grain microstructure with a uniform distribution of reinforcing particles is formed after the extrusion process. Comparing the extruded samples to the unprocessed samples reveals a larger grain size after extrusion. The absence of MAX phase particles causes the formation of finer grain size in the extruded sample. Under the influence of heat and plastic strain, a reactive layer containing a solid solution of Cu(Sn) or Cu3Sn compounds is formed at the interface of the particle and the copper matrix. By performing the extrusion process, the reactive layer at the interface is broken and scattered on the copper matrix. Furthermore, by applying MAX phase reinforcing particles and performing the extrusion process, the copper matrix's hardness, tensile strength, and wear resistance increase by 128, 99, and 84%, respectively. The five vol% Ti2SnC MAX phases in the extruded copper matrix composite wire results in 7.3% reduction in electrical conductivity.

Secure Data Processing Technology of Distribution Network OPGW Line with Edge Computing

Promoted by information technology and scalable information systems, the network design and communication method of optical fiber composite overhead ground wire (OPGW) have been in great progress recently. As the overhead transmission line has strict requirements on the outer diameter and weight of OPGW, it is of vital importance to perform the physical-layer secure data processing for the distribution network OPGW line with edge computing. To this end, we examine a physical-layer secure distribution network OPGW with edge computing in this article, where there exists one transmitter S, one receiver D, one authorized legitimate monitor LM, and an interfering node I. To better analyze the system performance, we firstly give the definition of the system outage probability, based on the secure data rate. Then, we evaluate the system performance for the distribution network OPGW, by deriving analytical outage probability of secure data processing, to facilitate the system performance evaluation of secure data processing in the entire SNR regime. Finally, we demonstrate some simulation results to validate the analytical results on the physical-layer secure distribution network OPGW line with edge computing.

INCREASING THE WEAR RESISTANCE OF HEAVY LOADED FRICTION UNITS OF ANTI-FRICTION GAS THERMAL COATINGS

Purpose. The purpose of this study is to establish technological conditions and parameters for obtaining materials for improving the performance of machine parts under conditions of heavily loaded friction units due to quasi-tribosystems of gas thermal sprayed anti-friction layers.
 Research methods. Priori data were used in combination with our own scientific developments of the dependences of the influence of the chemical composition of gas thermal sprayed anti-friction layers on the physical and mechanical properties of the surface layer of the material, which is destroyed under tribosystem conditions.
 Results. On the basis of the theoretical and practical scientific research, a set of relevant knowledge has been obtained, which makes it possible to determine the main criteria requirements for obtaining anti-friction layers and graphically describe the characteristics of the alloy and show the correlations of the parameters with each other. The positive role of aluminum as a soft component of anti-friction pseudoalloys, which is well sprayed by thermal metallization at an affordable cost, has been experimentally confirmed. It has been proven that gas thermal coatings in the form of pseudoalloys, consisting of particles with different physical and mechanical properties of materials, can have up to 2–3 times higher wear resistance compared to single-component coatings from materials included in the composition.
 Scientific novelty. Theoretical and practical scientific research with the reproduction of system analysis to increase the resistance to destruction under the conditions of quasi-tribosystems of gas thermal sprayed antifriction layers is given. It is shown that in order to ensure a good running in of the contacting surfaces in the friction zone and particles of hard material with high wear resistance and resistance against sticking with the counterbody, anti-friction pseudoalloys of coatings should contain zones of material particles with lower hardness to comply with the Charpy principle. It has been determined that when spraying composite wires for application as a solid component of anti-friction coatings, it is possible to use particles of alloying elements that form intermetallic compounds or phase components of alloys with a high hardness during melting. A comparative analysis showed that two-component coatings deposited with composite wires are characterized by higher hardness and wear resistance under high contact pressures compared to coatings of the same composition deposited with different types of solid wires.
 Practical value. The obtained results allow, within the framework of technical and technological accuracy, which is necessary in the practical engineering forecasts, to determine the physical and mechanical properties of wear resistant gas thermal sprayed anti-friction layers under conditions of quasi-tribosystems. Thus, in comparison with cast antifriction materials of the same composition, anti-friction layers obtained by thermal metallization have a 1.5–1.8 times higher wear resistance.

Research on Communication Technology of OPGW Line in Distribution Network under Interference Environment

In optical fiber composite overhead ground wire (OPGW) networks, the current monitoring is mainly through installing electronic sensors on the cable and manually monitoring the video on the cable, where the interference plays an important role in the communication and monitoring based systems. In essence, the interference arises from aggressive frequency reuse, especially in the frequency-limited Internet of Things (IoT) networks. The existence of interference causes a negative effect on the system performance of communication systems and IoT networks including the OPGW networks. Hence, this article investigates the communication technology of OPGW line in distribution network under interference environment, where there is one primary link, one secondary link, and one legitimate monitor listening to the secondary link. The secondary user needs to transmit its message to the secondary receiver under the interference power constrained by the primary node. We firstly define the outage probability of legitimate monitoring based on the data rate, and then analyze the system performance by theoretically deriving a closed-form expression of the outage probability for the OPGW communication under interference environment. Simulation results are finally demonstrated to verify the correctness of the closed-form expression for the OPGW communication under interference environment, and show that the interference has a negative impact on the OPGW communication performance.

Cable conductor of cabling and wiring products based on composite materials for transport systems

The article deals with the issues of working out the technology of manufacturing cabling and wiring products that are used in railway transport systems. A cable conductor for a cable product, made on the basis of composite materials, was adopted as the object of research. The technology of production of composite billets and wire for cable products for subsequent drawing, as well as ways of obtaining them, is covered in detail. Special attention is paid to the problems of operation in railway transport, power transmission systems, which confirms the relevance of the research. The increase in the cost of the finished product is due to the violation of the technology, which is associated with the structural diversity of the layers of the composite long-length billet, determines the need to maintain the constancy of its plastic properties along the entire length. By means of a generalized mathematical model of the drawing process and on the basis of reference data, calculated parmeters of technological extracts were obtained for the layers of the composite billet to be drawn. The results of the research work made it possible to develop a methodology for calculating the technological modes of operation of the drawing machine and to determine the optimal technological parameters of the technological equipment.

Overview of new heat-resistant multi-capacity wire

With the rapid development of the country's economy, the demand for electricity is becoming greater and greater. In order to achieve increased capacity of power lines, the use of new heat-resistant capacitance conductors has become an inevitable trend. Capacity-enhancing conductors are conductors that increase the line's power transmission capacity by raising the conductor's operating temperature or increasing its cross-sectional area. This review discusses new heat-resistant aluminum stranded wires, mainly heat-resistant aluminum stranded wires and composite core wires, and describes the mechanism for increasing the capacity of these wires.

Fabrication of a 3D Porous Silver Wire Based on a Template-Assisted Electroless Deposition Method

Porous metal wires are promising in various applications, such as catalysis, energy storage and conversion, electrochemical sensing, and so forth. However, controllable fabrication and structural tuning of porous metal wires remains a daunting challenge. Here, we report the fabrication of 3D porous silver wires based on a template-assisted electroless deposition (ELD) method using an electrospinning-derived elastomer yarn as the template. After the calcination, the elastomer yarn with the deposition of silver nanoparticles can be converted into a 3D porous metallic silver wire with a conductivity higher than 3600 S/cm and a porosity of 86%. The porous structure of the wire could be tuned by changing the repeating cycles of the ELD process for loading silver nanoparticles. More importantly, the electrospinning-based fabrication strategy enables us to incorporate an insulating fibrous layer on the silver wire to impart advanced functionalities. As a proof of concept, a porous silver wire containing a concentric layer of SiO2 microfibers was prepared, and its application as a wire-shaped capacitor for liquid sensing was demonstrated. Benefitting from its completely inorganic nature, high porosity, and chemical stability, the composite wire could sense various organic solvents as well as aqueous solutions with high sensitivity, reliability, and long-term-use stability.

Nonlinear static and dynamic mechanical behaviors of Nb3Sn superconducting composite wire: experiment and analysis

Nonlinear static and dynamic mechanical behaviors of Nb3Sn superconducting composite wire: experiment and analysis

Ultrastrong Carbon Nanotubes–Copper Core–Shell Wires with Enhanced Electrical and Thermal Conductivities as High-Performance Power Transmission Cables

Demands for high-performance electrical power transmission cables continue to rise, especially for offshore power transmission, electric vehicles, portable electronics, and deployable military applications. Carbon nanotubes (CNTs)-Copper (Cu) core-shell wire is regarded as one of the best candidate material systems for transmitting electricity and thermal energy. In this study, a facile and robust approach was developed to enhance the CNT-Cu interfacial interactions. This approach consists of a substrate-enhanced electroless deposition step for Cu pre-seeding and thiol functionalization. Benefiting from the thiol-activated CNT surface and Cu seed deposit, the CNTs-Cu core-shell wire forms a densely packed Cu shell with a void-free CNT-Cu interface. Consequently, the CNTs-Cu core-shell wire possesses (1) superior specific strength (eightfold stronger), (2) 30% higher specific conductivity, (3) 120% higher specific ampacity, and (4) an impressive 110% higher thermal conductivity compared with pure Cu wires. Moreover, this composite wire still maintains its structural integrity and electrical properties over 600 cycles of the fatigue bending test, rendering this system an excellent candidate for high-performance electrical cable and conductor applications.

Study on Distribution Characteristics of Induced Voltage and Current on Optical Fiber Composite Ground Wire of Distribution Line

The OPGW of the distribution line combines communication and lightning protection. During the electromagnetic coupling process among power distribution lines, induced voltage and induced current will be generated on OPGW. This threatens the safety of power operation and maintenance personnel. This paper uses the ATP-EMTP software to build the electromagnetic coupling model of a 10kV single-loop distribution line with the OPGW. Factors including OPGW grounding mode, OPGW grounding resistance, OPGW relative position, and line load are considered, and the influence of different factors on the induced voltage and current on the OPGW of the distribution line is compared and analyzed in detail. The simulation results show that the ground resistance and relative position have little effect on the induced voltage and induced current of the OPGW. Grounding mode and line load greatly influence the induced voltage and induced current of the OPGW. The simulation conclusion provides a certain theoretical basis for selecting the parameters of OPGW of a 10kV single-circuit distribution line.