Metallic Woven Research Articles

РАСЧЕТ ОСНОВНЫХ ТЕХНОЛОГИЧЕСКИХ ПАРАМЕТРОВ ПРОЦЕССА ПРИ ЭКП МЕТАЛЛИЧЕСКОЙ ТКАНОЙ СЕТКИ К ВАЛАМ ИЗ СТАЛИ 45

When welding metal woven meshes to samples made of steel 45 (similar AISI 1045) by electric contact welding (ECW), a welded joint is formed in the solid phase. The article presents calculations of the main technological parameters of electrocontact welding of metal woven grids to samples made of 45 steel to ensure the continuity of the restored surface and obtain a coating with a given thickness: current strength, forces pressing roller electrodes to the part and the time of the current pulse.

Calculation and Experimental Estimation of the Thickness of a Coating Formed by Electrocontact Welding of a Metal Woven Mesh onto Bronze Parts

Calculation and Experimental Estimation of the Thickness of a Coating Formed by Electrocontact Welding of a Metal Woven Mesh onto Bronze Parts

Pore scale analysis for flow and thermal characteristics in metallic woven mesh

Metallic woven mesh screens are representative porous media with periodic structures, which have great application prospects in emerging technology and industrial equipment. However, the effect of their pore structure on macroscopic properties is not clear, which limits their large-scale engineering application. In this paper, to investigate the influence mechanism of stacking patterns and wire contact conditions on flow and heat conduction from the pore scale, a representative elementary volume model of the square-shaped plain copper micromesh was reconstructed according to the geometric parameters obtained by the optical microscope and porosity test experiment. Furthermore, based on the understanding of microscopic mechanism, the theoretical calculation model for macroscopic characteristics was proposed. The results show that the flow characteristics in meshes are mainly affected by stacked patterns. When ReK is 0.08 and 0.28, the flow in single layer and staggered stacked woven meshes transitions from Darcy flow to Forchheimer flow. In Forchheimer flow regime, neglecting the inertia force causes a maximum 50 % error for permeability calculation. The permeability empirical correlations for Darcy and Forchheimer flow are proposed according to Kozeny-Carman and Kozeny-like model. The z-direction effective thermal conductivity of copper woven meshes is significantly affected by wire contact conditions, the maximum value is from 2.5 to 13.5 W/(m·K). The z-direction effective thermal conductivity of tangent and gap contact conditions can be described by the ZBS model, while the random model is suitable for that of overlapped contact conditions. The x-direction thermal conductivity is little affected by contact conditions, the maximum value is 50.3 W/(m·K), but the tortuosity effect of copper wires should be considered for calculation. The calculation model of anisotropic thermal conductivity for single-layer woven meshes is established according to Kirchhoff's law, which is also extended to the staggered stacked woven meshes by introducing a compactness factor.

Terahertz narrow bandpass filters based on double-layer metallic woven meshes with engineered Fabry-Perot cavities

In this work, a new narrow bandpass filter based on double-layer metallic woven meshes (MWMs) is experimental and numerically investigated. Differing from generally reported 2D planar structures, the MWM is a 3D structure consisting of metal cross-bending wires. Multiple resonant peaks with high isolation originating from the Fabry-Perot cavities are achieved by changing the distance between two MWM layers. Simulated results show that an optimized double-layer MWMs presented a sharp resonant peak whose full width at half maximum is narrower than 1.25 GHz. The achievement of such filters based on the engineered Fabry-Perot cavity would provide a new method for the design of ultra-narrowband filters and ultra-sensitive sensors in terahertz regions.

Successful Wallstent exclusion of iliofemoral venous aneurysms—a new treatment paradigm

Treatment of venous aneurysms involving the iliac and femoral veins has generally been an open surgical approach, with a few case reports noting use of an endovascular approach. We report three cases: (1) a patient with an iliocaval occlusion involving an occluded TrapEase filter who presented with a large left external iliac vein aneurysm; (2) a patient with a left common femoral vein aneurysm; and (3) a patient with left profunda femoris vein aneurysms with associated pulmonary embolism. All three patients were successfully managed with the use of appropriately sized bare metal woven stents (Wallstents; Boston Scientific). Their clinical presentation, technical considerations, and outcomes are reviewed.

Dynamic and quasi-static mechanical behavior of 3D metallic woven lattices

Complex mechanical systems can generate severe dynamic environments that require materials with optimized combinations of damping properties, elastic moduli, and service temperatures. In this study, woven lattices were manufactured with stainless steel (SS) and copper (Cu) wires via a three-dimensional (3D) weaving process to form SS, Cu, and SS–Cu lattices. Following fabrication, selective bonding using Cusil® was applied to either one or both sides of the SS–Cu weaves to form single-sided bonded SS–Cu composite (B1C) lattices and double-sided bonded SS–Cu composite (B2C) lattices. Measurements of dynamic and quasi-static mechanical properties of both unbonded and bonded weaves demonstrate that all three unbonded lattices exhibit high loss factors with a relatively low normalized effective elastic modulus. In contrast, the bonded SS–Cu lattices exhibit lower loss factors but higher normalized effective elastic moduli. We attribute the high loss factors and relative low moduli to wire rearrangement during deformation in the form of wire sliding and rotation that becomes partially inhibited when we bond Cu wires on one or both sides of the SS–Cu weaves. We discuss sources for the observed variations in properties and demonstrate an ability to both tune and obtain exceptional damping and moderate stiffness in architected metallic lattices.

An enhanced triboelectric nanogenerator with micro-grid patterned PDMS for self-powered sensing and music playback

In latest years, TENGs are used in a wide range of fields. However, the low output performance of TENGs prevents them from continuously supplying power to devices, which motivates us to reduce this limitation. Currently, several studies have been conducted to improve the output performance of TENG by increasing the specific surface area of friction materials through plasma treatment, photolithography, and other methods. Yet the common methods are too cumbersome and expensive. In this work, we proposed a triboelectric nanogenerator with micro-grid patterned PDMS(X-TENG) using a metal woven test sieve as a mold and a modified thermal embossing technique, which is low-cost, easy-to-make, mass-produced. The micro-grid pattern is roughly square and the side lengths d of the pattern is 5000 μm, 500 μm, 50 μm, and 5 μm, respectively. As d gradually decreases, the specific surface area SS increases, the charge density on the surface (σ) increases, moreover, the performance is improved. When d is 5 μm, X-TENG has the optimal capability with 1.5 times the short-circuit current and 2.3 times the open-circuit voltage of a TENG composed of smooth PDMS film (S-TENG). In addition, X-TENG serves as a self-powered sensing to monitor human health for application. X-TENG also acts as a self-powered control device, which implements the state change of the Linux-based Raspberry Pi 4B pressurized music player. Hence, the X-TENG holds great promise for intelligent sensing and self-powered supply.

Comparison of methods for measuring and investigating water permeability of woven filter media

This paper presents, discusses, and compares three methods for measuring the water permeability of metal woven meshes. Two pieces of equipment were designed for this purpose. The first uses declining pressure – falling head method (FHM). The other uses constant pressure – the constant head method (CHM). The results obtained with these two empirical methods were compared with the fluid flow simulation through the studied samples. The results showed that each studied technique provided valuable and unique information for the water permeability investigation. All three techniques were in good agreement when they all worked under turbulent flow conditions. These conditions were observed for the samples whose pore size was above 30 µm. FHM worked only under turbulent flow. Therefore, it was recommended to work with high permeable samples. The samples whose pore size was below 30 µm required laminar flow. CHM could provide these conditions. This method was also the fastest with the lowest standard deviation value. It is recommended as the basis for forming a standard for measuring the water permeability of woven filter media. Data AvailabilityThe datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request.

Polarization- and angle-dependent performances of terahertz three-dimensional metallic woven meshes

The transmission performance of three-dimensional metallic woven meshes (MWMs) is first investigated at terahertz frequencies, which is found to depend on incident polarizations and angles. A mode-splitting phenomenon occurs when the incident angle of transverse magnetic waves is oblique and above 25°. The low-frequency dip exhibits a similar modal pattern to that of surface modes. But the high-frequency dip exhibits an asymmetric field distribution, originating from the coupling between surface modes and the MWMs modes. Experimental and numerical results demonstrate that the polarization- and angle-dependent performances of the MWMs enable the mesh to be flexible for THz wave manipulations.

Wire weaving for all applications

Metal woven wire cloth is used everywhere in industry, research, the building trade and many aspects of everyday life, from flow filters in water taps to precision filter elements in space craft. Haver & Boecker explains how woven wire cloth fulfils a variety of requirements and is fundamental to the areas of application.

DIFFUSION-VACUUM TECHNOLOGY OF MANUFACTURING LARGE AXISYMMETRIC ASSEMBLIES OF METAL MESH MATERIALS FOR HEAT EXCHANGE PATHS

Requirements for improving the reliability, service life, and increasing a specific pulse of liquid-propellant rocket engines justify a need for transfer to new designs and manufacturing technologies of regenerative engine cooling system. The paper describes a advanced diffusion-vacuum technology of manufacturing a regenerative cooling circuit for liquid-propellant rocket engine based on the concept of inter-channel coolant transpiration through a porous metal mesh material. The method of diffusion welding of metal wire mesh in vacuum makes it possible to obtain large axisymmetric blanks of metal mesh materials necessary to manufacture the regenerative cooling path of the liquid-propellant rocket engine and recuperative heat exchanger (RHE). The possibility of developing a high-efficient low-gradient porous heat exchange path obtained using a metal mesh material (MMM) has been experimentally confirmed. It is recommended to use metal woven cloth and twill filter screens of standard size П24–П60, С120 as a basic material for manufacturing MMM. Key words: diffusion-vacuum technology, porous mesh material, regenerative cooling system, inter-channel coolant transpiration.

Sharp resonances in terahertz free-standing three-dimensional metallic woven meshes.

Free-standing structures that do not require any holder or substrate show high levels of flexibility and stretchability and hence are well-suited for THz applications. In this work, a free-standing three-dimensional metallic woven mesh is experimentally and numerically investigated at terahertz frequencies. Such mesh fabricated by weaving techniques exhibits sharp Fano-like resonances, which has not been found in previous studies. Investigation results indicate that the high Q resonances originate from the bending effect in bent wires, which can be termed as Wood's anomalies. The resonance field longitudinally covers the input and output end faces of the woven mesh, thereby obtaining a large field volume. These properties in this kind of meshes are well suited for wave manipulation and biomolecular sensing in the terahertz regime.

Treatment of Peripheral Aneurysms - Dual Supera for Popliteal Artery Aneurysms: Immediate and Long-Term Results

Popliteal aneurysms have the highest incidence of all peripheral aneurysms. The clinical symptoms are dominated by chronic embolism, resulting in irreversible ischemia with the associated risk of amputation and mortality, but rupture is less important. Acute aneurysm thrombosis bears a high risk of amputation and mortality. Endovascular exclusion with covered stents instead of open surgery has gained widespread acceptance and is based on reliable data. The principle of flow diversion for aneurysm treatment is well known for the cerebral vasculature, and is now emerging as a potential alternative with promising results and is challenging the concept of complete endovascular aneurysm exclusion or surgical bypassing. Since 2011, thirty-four out of 142 electively treated popliteal aneurysms and 8 thrombosed aneurysms were treated with a bare metal woven Nitinol stent. In this single centre series with continuous mid- to long-term follow-up, as described below, this option showed reliable results in terms of clinical outcome, material fatigue and preservation of outflow vasculature with the option for conversion. The limitation of the technique is determined by the available maximum outer stent diameter of 7.5 mm.

Electrospun Nanofiber Mats with Embedded Non-Sintered TiO2 for Dye-Sensitized Solar Cells (DSSCs)

TiO2 is a semiconductor that is commonly used in dye-sensitized solar cells (DSSCs). However, the necessity of sintering the TiO2 layer is usually problematic due to the desired temperatures of typically 500 °C in cells that are prepared on polymeric or textile electrodes. This is why textile-based DSSCs often use metal fibers or metallic woven fabrics as front electrodes on which the TiO2 is coated. Alternatively, several research groups investigate the possibilities to reduce the necessary sintering temperatures by chemical or other pre-treatments of the TiO2. Here, we report on a simple method to avoid the sintering step by using a nanofiber mat as a matrix embedding TiO2 nanoparticles. The TiO2 layer can be dyed with natural dyes, resulting in a similar bathochromic shift of the UV/Vis spectrum, as it is known from sintered TiO2 on glass substrates, which indicates an equivalent chemical bonding. Our results indicate a new possibility for producing textile-based DSSCs with TiO2, even on textile fabrics that are not high-temperature resistant.

Numerical and experimental study of the penetration of a package of woven metal grid by a steel ball

AnnotationThe results of numerical and experimental studies of the penetration and punching by a steel ball of the barriers consisting of packages of metal woven wire grid are presented. In the experiments performed, a packet of meshes was formed by overlaying ten flat woven layers with different sizes of quadrilateral cells. The ball was made of high-strength steel with high yield strength, so that after the experiments it remained intact. Numerical calculations were carried out using the author’s program based on a modification of the Godunov method for the calculation of elastic plastic deformation taking into account the accumulation of damage and destruction. Comparison of experimental and calculated data is carried out by fixing the speed of a ball flying behind a barrier and a general dynamic picture of the development of zones of destruction in a barrier.

ЭКСПЕРИМЕНТАЛЬНОЕ ОПРЕДЕЛЕНИЕ КАПИЛЛЯРНОГО РАДИУСА ЯЧЕЕК СЕТОК С ДЕФОРМИРОВАННОЙ СТРУКТУРОЙ ПЛЕТЕНИЯ

The article is devoted to the experimental study of the change in the capillary radius of cells of metal woven nets, depending on the degree of deformation of the structure of their weaving. The values of the measurements of the capillary radius of the cells are given as a function of the interlacing angle of the fibers of the nets. Recommendations are given on the possibility of using deformed nets in devices to ensure the continuity of the components of the fuel tanks of spacecraft.

ЧИСЛЕННОЕ МОДЕЛИРОВАНИЕ УПРУГОПЛАСТИЧЕСКОГО ДИНАМИЧЕСКОГО И СТАТИЧЕСКОГО СЖАТИЯ ПАКЕТОВ МЕТАЛЛИЧЕСКИХ ПЛЕТЕНЫХ СЕТОК

Multilayered packages of metallic woven grids are used for protecting the vessels of explosion chambers and other structures from fragmentation damage and pulsed effects. A grid package is basically formed by stacking up several layers, observing the direction of the wires; that is why such a package can be considered to be a highly-porous deformable structural element with orthotropic properties. Earlier experimental studies made it possible to construct deformation curves for porous packages of woven grids under dynamic and static compression normal to the layer. To find out factors causing differences in dynamic and static deformation curves, normal compression of a symmetric fragment of woven grids under dynamic and static loading modes observed in the experimental studies was numerically modeled. The 3D processes of elastoplastic deformation of a fragment of a woven metallic grid, accounting for contact interaction between the wires, were numerically modeled with the help of computational systems ANSYS and ANSYS LS-DYNA using FEM. The analyzed area consisted of four 3D cylindrical bodies. Compression was applied with a pair of ideally rigid plates, symmetrically approaching each other. The deformational behavior of the wires was described using the model of plasticity with isotropic hardening. To obtain reliable computational results, a static deformation diagram was constructed for the steel the grid was made of. The effect of time limitation of the loading pulse was studied, as well as the effect of the difference in the static and dynamic deformation diagrams of the material of the grid. It is shown that the main effect on the dynamic behavior of the fragment of a porous package of steel grids is caused by the dynamic properties of the wire material, i.e., by the difference between the dynamic and static deformation diagrams. The final duration of the loading pulse and friction between the wires do not have any significant influence for that type of grids.

Metal Nanowire-Coated Metal Woven Mesh for High-Performance Stretchable Transparent Electrodes.

This work presents a new template-assisted fabrication method to obtain stretchable metal grids for high-performance stretchable transparent conducting electrodes (TCEs). Readily accessible metal woven mesh (MWM) is used as a template to make the fabrication process simple, cost-effective, reproducible, and potentially scalable by combining it with silver nanowire (AgNW) coating and elastomer filling processes. Stretchable TCEs are made with the AgNW-coated MWM and show remarkable optoelectronic performance with a sheet resistance of ∼3.2 Ω/sq and optical transmittance of >80%, large maximum stretchability of 40%, and electrical and mechanical robustness even under repeated stretching and bending deformations (1000 cycles). The device is demonstrated in a highly flexible touch screen panel that can operate well even in a bent state.

Pressure drop measurements for woven metal mesh screens used in electrical safety switchgears

The paper deals with an experimental investigation of the pressure drops and friction factors induced by sets of metal woven screens in the case of an incompressible fluid flow, namely water flow. These woven screens are of metallic type and are used in electrical safety devices, especially at the end of exhaust duct of low voltage circuit breakers. In a first step, the whole of the set-up is used to check some approximations dedicated to pressure drops due to sphere beds around 275µm and 375µm as diameters. Results are discussed in terms of Darcyan and non-Darcyan permeabilities compared with published data and are analyzed in terms of the Blake-type friction factor. In the second step, the pressure drops are measured for stacks composed of eight different woven screens (of plain dutch type) formed with millimetric wires. Various formulations of the pressure drops and friction factors published elsewhere are tested with a special care dedicated to the choice of the geometry for the flow pattern (hydraulic diameter, spherical diameter, cylindrical diameter) and to the consideration of laminar and turbulent contribution. We then give the formulation that characterizes the fluid flowing through stacks of woven screens used in electrical safety applications.

Hydrodynamic model of screen channel liquid acquisition devices for in-space cryogenic propellant management

Technologies that enable the storage and transfer of cryogenic propellants in space will be needed for the next generation vehicles that will carry humans to Mars. One of the candidate technologies is the screen channel liquid acquisition device (LAD), which uses a metal woven wire mesh to separate the liquid and vapor phases so that single-phase liquid propellant can be transferred in microgravity. In this work, an experiment is carried out that provides measurements of the velocity and pressure fields in a screen channel LAD. These data are used to validate a new analytical solution of the liquid flow through a screen channel LAD. This hydrodynamic model, which accounts for non-uniform injection through the screen, is compared with the traditional pressure term summation model which assumes a constant, uniform injection velocity. Results show that the new model performs best against the new data and historical data. The velocity measurements inside the screen channel LAD are used to provide a more accurate velocity profile which further improves the new model. The result of this work is a predictive tool that will instill confidence in the design of screen channel LADs for future in-space propulsion systems.