Metallic Woven Research Articles

Numerical Simulation of Flow Resistivity of Metal Woven Mesh

Numerical Simulation of Flow Resistivity of Metal Woven Mesh

Study the Mechanical Properties of Polyethylene Reinforced by Metal Woven Fibers

Strength and Durability of fiber reinforced polymer composites (FRP) are controlled by the durability of their constituents: reinforcement fibers, resin matrices, and the status of interfaces. A great deal of research has been focused on the relationship of fibers with matrix, on the other hand, the diameter of the fiber and properties of fiber-matrix composites. The present investigation aims to study the effects of adding steel woven fibers to polymer (polyethylene) on some mechanical properties for resulting composite materials. This research tries to study the using of metal woven fibers as a reinforcement Material with Matrix from polyethylene grades (LDPE,LLDPE) as a composite material that was prepared using an injection molding process at 180- 200 Co and 60 rpm with different diameter (0.25- 1.0 mm).the results show that the tensile strength will slightly increase with percentage about (9%-18%) for the LLDPE and LDPE polymer composite respectively, and tensile modulus will significant increase about (80%- 190%) with woven metal fibers .The ductility is decrease with 68% for LDPE but it was 78% for LLDPE . The flexural strength will decrease with percentage about (36%-22%) for the LLDPE and LDPE polymer composite and impact strength with percentage about (78%-68%) and impact strength about (47%-40%) for the LLDPE and LDPE polymer composite respectively

Characterization of the Orthotropic Elastic Constants of a Micronic Woven Wire Mesh via Digital Image Correlation

Woven structures are steadily emerging as excellent reinforcing components in dual-phase composite materials subjected to multiaxial loads, thermal shock, and aggressive reactants in the environment. Metallic woven wire mesh materials in particular display good ductility and relatively high specific strength and specific resilience. While use of this class of materials is rapidly expanding, a significant gap in property characterization remains. This research classifies the homogenized, orthotropic material properties of a representative twill dutch woven wire mesh through the use of in-plane uniaxial tensile experiments incorporating a Digital Image Correlation (DIC) strain measurement technique. Values for elastic modulus and Poisson’s ratio are calculated from the experimental data, and shear modulus values are identified by means of constitutive modeling. This approach establishes a reproducible method for characterizing the in-plane elastic response of micronic metallic woven materials via macro-scale uniaxial tensile tests, and shows that a homogenous orthotropic constitutive model may be employed to describe the macro-scale elasticity of this class of materials with reasonable accuracy.

Yield Characteristics of a Twill Dutch Woven Wire Mesh Via Experiments and Numerical Modeling

Woven structures are steadily emerging as excellent reinforcing components in composite materials. Metallic woven meshes, unlike most woven fabrics, show high potential for strengthening via classical methods such as heat treatment. Development of strengthening processes for metallic woven materials, however, must account not only for behavior of the constituent wires, but also for the interactions between contacting wires. Yield behavior of a 325 × 2300 stainless steel 316L (SS316L) twill dutch woven wire mesh is analyzed via experimental data and 3D numerical modeling. The effects of short dwell-time heat treatment on the mechanical properties of this class of materials is investigated via uniaxial tensile tests in the main weave orientations. Scanning electron microscopy (SEM) is employed to investigate the effects of heat treatment on contacting wire interaction, prompted by observations of reduced ductility in the macrostructure of the mesh. Finally, the finite element method (FEM) is used to simulate the accumulation of plastic deformation in the mesostructure of the mesh, investigating how this wire level plasticity ultimately affects global material yielding.

Numerical simulation of interaction of deformable gas-permeable packets of grids with shock waves

A mathematical model that describes a one-dimensional approximation of interrelated processes of unsteady deformation of plane, cylindrical, and spherical packets of metallic woven grids and wave processes in the gas contained in pores is presented. Nonlinear equations of dynamics of two interpenetrating continua are solved numerically with the use of a modified Godunov scheme. Solutions of problems of the shock wave impact on plane and cylindrical packets of grids are obtained. Numerical results are found to agree with available experimental data. The character of explosive waves passing through a cylindrical packet of grids is studied.

Method of reducing the influence of speckles when processing diffraction patterns from moving woven materials

A program has been developed that makes it possible to reduce the noise level determined by the presence of speckles when woven materials are being monitored by laser diffraction. It is shown that, when one accumulates (adds up) the diffraction patterns obtained from metallic, synthetic, or carbon woven fabrics and considers the ratio of the intensity of the principal interference maxima in the cumulative diffraction pattern to the intensity of the speckles observed in them, one observes a growth of this ratio proportional to the number of additions. These results are explained on the assumption that the appearance of speckles in the diffraction pattern is caused by diffraction from randomly located inhomogeneities in the structure of the fabric that are always present inside the repeats of the weave in the illuminated section of the fabric.

5:1의 형상비를 갖는 사각덕트에서 직조 스크린 리입(rib)이 열전달과 마찰계수에 미치는 영향

직조 금속 스크린 리브(rib) 이 바닥에 설치된 사각 덕트에서 열전달과 유체유동의 압력강하를 측정하기 위해 실험적 연구를 수행하였다. 시험부의 치수는 200 mm(W) <TEX>${\times}$</TEX> 40 mm(H) <TEX>${\times}$</TEX> 712 mm(L)이고 수력직경은 66.6 mm이다. 입구영역에는 1.72m 길이의 가열되지 않은 동일한 치수의 채널을 설치하였다. 메쉬가 다른 4가지의 직조금속 스크린 리브에 대해 측정하였다. 그리고 비교를 위해 일체형 리브에 대해서도 측정하였다. 국부 열전달 계수의 측정에는 스테인레스 강제 포일(foil) 히터와 T형 열전대률 이용하였다. 레이놀즈 수는 23,000에서 58,000의 범위이다. 덕트의 수력직경(<TEX>$D_h$</TEX>)에 대한 직조 금속 리브의 높이(e)의 비(<TEX>$e/D_h$</TEX>)는 0.075 이고 리브 간격(p)과 높이의 비(p/e)는 10이다. 실험 결과 메쉬가 없는 일체형 리입에서 가장 누셀트 수와 마찰계수가 컷다.

Performance Analysis of Woven Wire Screen Matrix Heat Exchanger Units

The performance of a compact cryogenic heat exchanger with metal woven wire screen matrix units was studied. Using different structural parameters, the heat transfer and hydrodynamic characteristics of the units were analyzed. Comparative analysis was also performed on the impact of different unit geometries and on the operational parameters affecting heat transfer performance and resistance characteristics. Data were interpreted to derive relevant performance characteristics such as mass flow, heat load, temperature difference in heat transfer, Reynolds number, heat transfer coefficient, inlet and outlet temperature, and resistance losses, among others. This study also introduced the structural parameters of optimal hot and cold section proportions and the operational range of thermal parameters. The cryogenic heat exchanger of interest had a hot and cold cross-sectional area ratio of 0.44; when optimized, the unit can work within the temperature range of 80—295K with a mass flow between 0 and 1 g/s and a heat load from 35 to 400 W. This condition produced maximum heat exchanger efficiency at 94% with both hot and cold fluid flow resistances less than 3.0 kPa. The units can constitute a low-weight ratio with a larger specific surface area. Based on the principles of characteristic evaluation, the assessment results were presented based on an integrated feature of heat transfer units, which includes their thermal properties, resistance characteristics, and structural parameters, among others. The criterion for the improvement and performance optimization of the space applications of cryogenic woven wire screen matrix heat exchanger units was also proposed.

Damage detection of hybrid aramid/metal-PVB composite materials using optical fiber sensors

Embedding optical fiber sensors within laminar thermoplastic composite material results in forming a system known as 'smart structure'. These sensors present the information about the inner structure health during the material exploitation and especially in the case of exterior impacts when a geometric configuration or the property changes of the material should be expected. This paper evaluates the feasibility of the real-time monitoring of indentation and low energy impact damage in composite laminates from indentation loading and Charpy pendulum impact, using the embedded intensity-based optical fiber sensors. An optical fiber sensing system, which relies solely on monitoring light intensity for providing the indication of the composite structural health, offers simplicity in design and cost-effectiveness. For this, aramid/polyvinylbutyral (PVB) and aramid/metal/PVB laminates with embedded optical fibers were fabricated. Four configurations of woven composites were tested, namely, aramid/PVB, and aramid/metal/PVB in three stacking sequences of aramid and metallic woven layers. The initiation of damage and fracture during testing was detected by observation of the intensity drop of light signal transmitted through an optical fiber.

Metal woven wire cloth feeding system for gas bearings

The paper presents an experimental investigation of pneumatic resistances constructed using woven wire cloth. Tests were carried out on commercial Touraille stainless steel wire cloth featuring different mesh sizes. Two types of experiments were performed: (a) Mass flow rate through single resistances was measured with different upstream and downstream pressures and wire mesh sizes. (b) Pressure distribution and mass flow rate were measured on a pneumatic pad with a fine wire mesh feeding system. Two approaches of identification of the single resistances are discussed. Test results can be used as the basis for developing woven wire cloth pneumatic resistances whose conductance is equivalent to that of certain of the calibrated orifices normally used in gas bearings.

Observation of Propagating Brush Discharge on Insulating Film With Grounded Antistatic Materials

A propagating brush discharge (PBD) usually occurs on a highly charged thin film with a grounded metal backing plate and often becomes energetic enough to ignite a flammable gas/vapor and even a dust cloud. In an actual situation, a PBD is seen on the surface of a large-sized flexible intermediate bulk container (FIBC) during its filling and/or emptying processes in an industrial site when the fabric of the FIBC is highly insulating. Anticipating that a PBD could occur even on an antistatic FIBC if it were used with an insulating inner bag, various types of antistatic fabrics for FIBCs in contact with an insulating polyethylene terephthalate (PET) sheet were put to the test. An antistatic fabric was grounded, and the PET sheet on the fabric was charged with a corona charger. A PBD was then generated by approaching a grounded spherical electrode. The discharge patterns were observed, and the currents and charge amounts were measured. A thin metallic fiber woven on an insulating fabric was found to drastically enhance the transferring of charge during a PBD, probably because of the corona discharges emanating from the metallic fiber. The resistivity of the fabric also affected the charge transference. The incendiary nature of each mode of PBD was discussed.

Electropolymerized poly-4-vinylpyridine for removal of copper from wastewater

Electropolymerization of 4-vinylpyridine in anhydrous organic medium was performed for grafting poly-4-vinylpyridine (P4VP) on usual conducting substrates [J. Appl. Polym. Sci. 74 (1999) 1557]. The interfacial links between the polymer and the metal bring chemical and mechanical stability suitable for technological processes. Layers of few tens of nanometer were grafted on large specific area materials such as metallic woven cloths or carbon felts. Synthetic copper wastewater passed through the functionalized substrates laid in columns. Swelling properties of P4VP and basic properties of pyridine are conjugated to lead to a rapid complexation of copper ions. Expulsion of the ions from the polymer layer toward a concentrated bath could be operated either chemically or electrochemically. This “surface route” for removal of heavy metals from wastewater intends to minimize the use of chemical compounds at the regeneration stage.

A NEW SELF-EXPANDING LINED STENT-GRAFT IN THE DOG URETER: RADIOLOGICAL, GROSS, HISTOPATHOLOGICAL AND SCANNING ELECTRON MICROSCOPIC FINDINGS

Recurrent or intractable ureteral strictures pose a significant problem for the practicing urologist. Metallic stents have been used sparingly for this problem with varying success. We investigated the use of a stent-graft consisting of a metal stent lined with a porous biocompatible polymer to determine if the liner would prevent urothelial ingrowth. One ureter of each of 11 dogs was treated with either a metallic woven stent or stent-graft inserted retrograde via a midline cystotomy. Six bare wire stents (controls) and five lined with a new, porous, biocompatible, polycarbonate elastomer liner (Corethane [registered sign]) were placed. The animals were followed radiographically with intravenous urography (IVP) at 6 weeks and just prior to sacrifice (12 to 22 weeks). Gross, histological, and electron microscopic analyses were performed. The results demonstrate that all of the bare metal stented animals developed moderate to severe hydroureteronephrosis with significant urothelial hyperplasia and ingrowth through the spaces between the metal wires. The animals implanted with lined stents showed one instance of mild hydroureteronephrosis (observed radiographically but not grossly at time of sacrifice) and virtually no papillary in-growths of urothelium through the stent interstices. This obstructive phenomenon was prevented by the porous polymer lining. There was no evidence of biodegradation of the liner on scanning electron microscopy. Based upon these findings, the marriage of a biocompatible polymer which provokes minimal tissue reaction, and metallic stents which provide tremendous strength, seems to offer significant advantages when placed into the urinary tract to maintain ureteral luminal patency.