Shield Electrode Research Articles

A super-stretchable conductive film with strain-insensitive conductivity for stretchable EMI shielding materials and wearable capacitive strain sensors

Strain-insensitive conductive films as stretchable electromagnetic interference (EMI) shielding materials and stretchable electrodes are highly desired in wearable electronics. However, fabricating super strain-insensitive conductive films under a tensile strain higher than 400 % is still a great challenge. Herein, a super-stretchable conductive film based on the crumple-structured Ti3C2Tx nanosheets-single walled carbon nanotubes/stretchable substrate double-layers is designed for the stretchable EMI shielding materials and electrodes. The resulting film exhibits a strain-insensitive electrical conductivity as high as 3.01 × 103 S/m even at a strain up to 500 %, which endows the film with a high and stable electromagnetic interference shielding efficiency (EMI SE) value of ∼45 dB. More interestingly, the EMI SE value of the film remains nearly constant even after 2000 cycles of 500 % tensile strain, indicating the excellent long-term service stability as a stretchable EMI shielding material. Moreover, a capacitive strain sensor with extra-wide sensing range, ultra-high stability, and excellent durability is successfully achieved by employing the as-prepared films as stretchable electrodes. This work proposes a convenient strategy of strain-insensitive conductive film aiming to design stretchable EMI shielding materials and electrodes for wearable electronics.

Recent Functionalized Strategies of Metal-Organic Frameworks for Anode Protection of Aqueous Zinc-Ion Battery.

The inherent benefits of aqueous Zn-ion batteries (ZIBs), such as environmental friendliness, affordability, and high theoretical capacity, render them promising candidates for energy storage systems. Nevertheless, the Zn anodes of ZIBs encounter severe challenges, including dendrite formation, hydrogen evolution reaction, corrosion, and surface passivation. These would result in the infeasibility of ZIBs in practical situations. To this end, artificial interfaces with functionalized materials are crafted to protect the Zn anode. They have the capability to modulate the zinc ion flux in proximity to the electrode surface and shield it from aqueous electrolytes by leveraging either size effects or charge effects. Considering metal-organic frameworks (MOFs) with tunable pore size, chemical composition, and stable framework structures, they have emerged as effective materials for building artificial interfaces, prolonging the lifespan, and improving the unitization of Zn anode. In this review, the contributions of MOFs for protecting Zn anode, which mainly involves facilitating homogeneous nucleation, manipulating selective deposition, regulating ion and charge flux, accelerating Zn desolvation, and shielding against free water and anions are comprehensively summarized. Importantly, the future research trajectories of MOFs for the protection of the Zn anode are underscored, which may propose new perspectives on the practical Zn anode and endow the MOFs with high-value applications.

Desorption of Positive and Negative Ions from Areoles of Opuntia microdasys Cactus at Atmospheric Pressure: Cactus-MS.

The areoles and spines of cacti can be used to desorb ions of ionic liquids (ILs) by the mere action of an electric field into the atmospheric pressure (AP) interface of a mass spectrometer. The small cactus species Opuntia microdasys bears numerous very fine hairs on its areoles and tiny sharp spines that appeared suited to serve as needle electrodes sharp enough for field desorption of ions to occur. In fact, positive and negative ions of four ILs could be desorbed by a process analogous to AP field desorption (APFD). In contrast to APFD where activated field emitters are employed, the ILs were deposited onto one or two adjacent areoles by applying 1-3 µL of a dilute solution in methanol. After evaporation of the solvent, the cactus was positioned next to the spray shield electrode of a trapped ion mobility-quadrupole-time-of-flight instrument. Desorption of IL cations and IL anions, respectively, did occur as soon as the electrode was set to potentials in the order of ±4.5 kV, while the cactus at ground potential was manually positioned in front of the entrance electrode to bring the areole covered with a film of the sample into the right position. Neither did mixing of ILs occur between neighboring areoles nor did the cactus suffer any damage upon its use as a botanical field emitter.

Investigation of the Properties of Anti-Friction Coatings Deposited with Different Casting Methods.

This article presents the research results of depositing anti-friction coatings (Babbitt) using three different casting methods: static casting, flame soldering, and clad welding. Babbitt alloy coatings deposited with different casting methods are discussed and explained in terms of changes in the coating properties, such as the microstructure, hardness, strength, and chemical composition. The results showed significant differences in the aforementioned properties, depending on the chosen coating deposition method. The results of the tests confirmed the importance of using shielding gas during deposition to ensure the chemical composition of the coating. The analysis revealed that decreases in the amounts of antimony and copper in the Babbitt coating compared with the initial concentrations were influenced by selective evaporation, oxidation, and the coating process parameters associated with different coating methods. To maintain the desired balance of mechanical properties in Babbitt coatings, it is important to control the antimony and copper contents. Clad welding deposition using a non-consumable tungsten electrode and argon shielding gas achieved a chemically stable coating quite close to the initial chemical composition of the Babbitt alloy.

Multi-Weld Quality Optimization of Gas Tungsten Arc Welding for Aluminium 6061 using the Grey Relation Analysis-Based Taguchi Method

The optimization of parameters is crucial in the joining process, particularly in welding, to attain connections with exceptional mechanical properties. In the present study, the welding of aluminium 6061 was conducted with a TIG, an acronym for tungsten inert gas, is formally referred to as gas tungsten arc welding (GTAW) technique, employing a suitable ER 4043 electrode and argon shielding gas. The investigation of optimal welding parameters, specifically current, voltage, and flow rate, is conducted utilizing statistical methodologies such as the hybrid Grey-based Taguchi process. The desired attributes for high-quality welds were established as having high tensile strength, hardness, and a low rate of corrosion. Given the presence of three responses and one objective, the hybrid Grey-based Taguchi method is employed. The statistical approaches have converged on optimal parameters of 120 A, 20 V, and 15 L/min. The present analysis reveals that the ideal welded junction exhibited the following characteristics: a tensile strength of 190.169 MPa, a hardness value of 77HV, and a corrosion rate of 0.29 mm. The current parameter was found to have the highest contribution, accounting for 65.66% of the overall performance of the weldments. Confirmatory testing was conducted in order to confirm the optimization strategy, and the findings indicated that the Grey-based Taguchi technique is a straightforward yet effective approach for optimizing welded connections across several performance criteria.

Effect of Voltage Boundary Conditions on the Sensitivity and Design of Coplanar Capacitive Sensors

Coplanar capacitive sensors are widely employed in various applications due to their advantages in noninvasive evaluation, fabrication simplicity, and versatility. While there have been several experimental demonstrations, optimization of the boundary conditions and geometry is lacking. In this letter, we investigate the effect of both the voltage boundary conditions and the electrode geometry on the sensitivity with respect to an overlaid insulating layered structure. We perform electrostatic analysis using finite element simulations to study the distribution of electric fields between two coplanar electrodes, with various combinations of applied voltages and shielding electrodes beneath the sensing electrodes. By combining this analysis with variations in electrode geometry and permittivity distribution of layers, we demonstrate how specific geometries and material properties can amplify the effect of voltage boundary conditions. Our results indicate that incorporating conductive shielding electrodes can enhance the total capacitance while enabling increased sensitivity within regions close to the electrodes. Furthermore, our study reveals that conductive shielding electrodes are more effective in achieving higher sensitivity when the gap is of similar size to the electrode width. The outcomes of this research can facilitate the more efficient design of coplanar capacitive sensors, particularly for pressure sensing and proximity sensing applications where the overlaid material under test may undergo deformation.

Development and experimental investigation of the narrow-gap coated electrostatic precipitator with a shield pre-charger for indoor air cleaning

We designed and evaluated a two-stage electrostatic precipitator with a shield pre-charger and a narrow precipitator for indoor air cleaning. Unlike the conventional ESP-type air cleaner, the ion generation and particle charging regions were separated by a perforated plate with bias voltage. The electrical energization was achieved by connecting a large resistor in series with the shield electrode. A narrow-gap plate-plate precipitator was placed after the pre-charger for a strong electric field and a high specific collection area. The performance of the shield pre-charger, the narrow precipitator and their integration in lab-scale of 62 m3/h and pilot-scale of 500 m3/h were evaluated. The overall collection efficiency was 98.6 % and 75.5 % for gas flow velocities of 0.4 m/s and 1.2 m/s, respectively. The ozone concentration was around 0.2 ppm for a 24 h continuous operation. Our study showed a close relationship between particle charging and shield voltage with charging current, and a relatively stable performance under high gas flow velocity. The particle collection efficiency was 2.5 times higher than that of a conventional ESP-type air cleaner of similar size at a gas velocity of 1.2 m/s.

Different Welding Processes Using Statistical and Numerical Approaches Using the Fuzzy TOPSIS Method

Welding is for two or more parts heat; pressure or Linking is a fabrication process cooling of parts. Welding usually involves metals and Used in thermoplastics, but also in wood can be used. A finished welded joint May be referred to as good material. Welding such as metals, thermoplastics, and/or wood Applying heat or pressure to materials It is a process of joining them together. Cool those down Allow enable the connection. Different Processes and techniques unique to materials required there are some people items that are considered unusable. MIG welding uses an electrode wire and shield gas fed continuously through A lamp held in the hand. A consumable for TIG welding is tungsten uses an electrode, which is a supply line, and Shield through a separate, hand-held filler wire manually injected into the weld pool with gas. Research significance: Welding is two or more parts by heat, pressure, or both together Linking is a fabrication process. Welding is usually in metals and thermoplastics used, but can also be used on wood. The finished welded joint may be referred to as a weld meant. Gas pressure welding joins two base materials in under pressure by heating them with gas contact. Resistance spot welding two Combine the basic ingredients together heating up with heat generated by electrical resistance by conducting current. The basic purpose of welding is within a solid joint combining two elements. Welders in general Work with metal or thermoplastic and durable filler material to hold together are using Skyscrapers in our world, many modern ones like cars, ships, and planes Welding is used to make structures. Mythology: Alternative: Factorial designs, ANNs, GA, and RSM. Evaluation Option: Computational time, Experimental domain, Model developing, Availability in software, Optimization Accuracy level. Result: from the result it is seen that Model developing and is got the first rank whereas is the Availability in software got is having the lowest rank. Conclusion: The value of the dataset for Welding Process in Fuzzy TOPSIS method shows that it results in Model developing and top ranking.

The technique to symmetrize domain switching hysteresis loops in LiNbO3 domain-wall nanodevices with improved polarization retention

Ferroelectric devices have wide applications in nonvolatile random-access memories, sensors, actuators, and transducers. The built-in potential at the interfaces could result in poor polarization retention. Here, we found an effective way to independently adjust two coercive fields of LiNbO3 mesa-like domain wall devices in contact to two side electrodes at the surface. Taking advantage of the electrode shielding effect on the depolarization field across an interfacial layer, the near-zero coercive field increases almost linearly with respect to the extending length of one side electrode covering the tail of the reversed domain, enabling nonvolatile ferroelectric domain wall devices in good polarization retention and fast operation speeds.

Performance optimization of indirectly heated cathode based electron gun by controlling high voltage surface flashover and beam positioning at target plane

In this paper, an improved design of a practical 2700-bent, 60 kV, 60 kW, indirectly heated cathode-based electron gun has been proposed in order to reduce high voltage breakdown in the electron gun. This ensures reliable and uninterrupted operation of the electron gun for melting and evaporation applications. For this purpose, 1) shield electrodes have been optimally designed for gun insulators in order to provide desired voltage grading/shielding and 2) optimization of positioning of the gun electrodes and optimal current in Helmholtz coil in order to ensure desired 2700-bent electron beam at the target plane, have been achieved. A new optimization technique incorporating formulation of a 3-D cost function is developed and is implemented by using an open-source web application utilizing python script. Electrostatic and electromagnetic 3-D gun simulations are carried out by using CST Studio Particle Tracking Module with modified parameters. Trial experiments have been conducted to monitor breakdown signal which showed improvement in surface flashover performance of electron gun. Molybdenum tablets were successfully melted at target plane by achieving the desired 2700-bent electron beam. Dimensions of molybdenum melt pool and simulation results showed good correspondence.

Optimization of Shielding Electrode and Inner Shielding Structure for UHV Oil-gas Bushings with Improved Hybrid Algorithm Combining Particle Swarm Optimization and Back-Propagation Neural Network

With the development of prototype for UHV oil-gas bushings, E-field distribution around bushing end and structure optimization for shielding electrode is an important issue to be studied. The basic principles and processes of hybrid algorithm combining particle swarm optimization and back-propagation neural network (PSO-BP algorithm) has been discussed in this paper. The optimization capability and accuracy of proposed algorithm has been verified with continuous explicit function. The structure optimization of shielding electrode has been conducted using PSO-BP algorithm. The study shows that PSO-BP algorithm can seek extreme point of testing function exactly, and jump over trap of local optimal solution; three-dimensional full model of bushing is needed in E-field distribution calculation; PSO-BP algorithm has found the best structure parameters of shielding electrode, with which more even E-field distribution can be obtained, and maximum electric strength can be reduced by 64.9%, moreover, the computing time is about 75.2% less than traditional PSO algorithm. The study results have been applied in bushing prototype manufacture which has passed through all testing experiments. The optimization method proposed in the paper can also be used in optimization design for other complex insulation structures.

High-transmittance vertical-alignment liquid crystal display with subpixel electrode shielding electric field design

A proposed pixel structure named ‘Sub-pixel Electrode Shielding (SES)’ is developed to improve the transmittance of eight-domain vertical alignment liquid crystal display (LCD). In the SES pixel, the sub pixel electrode is designed to partially overlap with data line and encircle the main pixel to shield the effects of data signal on the common signal. Therefore, the array common electrode and data signal shielding lines of conventional pixel can be removed to enhance the aperture ratio. Results show that the 65 inch ultra-high-definition (UHD) LCD panel with this proposed SES pixel design achieves a transmittance of 5.9%, which is 7.3% higher than the panel with conventional pixel design, and shows the same viewing angle characteristic as the conventional one.

An Electric Field Microsensor with Mutual Shielding Electrodes.

This paper proposes an electric field microsensor (EFM) with mutual shielding electrodes. Based on the charge-induction principle, the EFM consists of fixed electrodes and piezoelectric-driving vertically-movable electrodes. All the fixed electrodes and movable electrodes work as both sensing electrodes and shielding electrodes. In other words, all the fixed and movable electrodes are sensing electrodes, and they are mutually shielding electrodes simultaneously. The movable electrodes are driven to periodically modulate the electric field distribution at themselves and the fixed electrodes, and the induced currents from both movable and fixed electrodes are generated simultaneously. The electrode structure adopts an interdigital structure, and the EFM has been simulated by finite element methods. Simulation results show that, since the sensing area of this EFM is doubled, the variation of induced charge is twice, and therefore the output signal of the sensor is increased. The piezoelectric material, lead zirconate titanate (PZT), is prepared by the sol–gel method, and the microsensor chip is fabricated.

Surface plasmonic resonance tunable nanocomposite thin films applicable to color filters, heat mirrors, semi-transparent electrodes, and electromagnetic-shields.

This study proposes a plasmonic resonance-tunable nanocomposite thin film, which applies to a color filter, heat mirror, semi-transparent color electrode, and electromagnetic shield, given that the size and structure of nanoclusters can be controlled by a sputtering power density. The structural and functional properties of silver/plasma-polymer-fluorocarbon (Ag/PPFC) nanocomposite thin films, which were sputtered by ternary composite targets, were investigated with various compositions and sputtering power densities. The growth of Ag nanoclusters of the thin film was suppressed as the sputtering power density increased due to the rich functional group of -CFx- fluorine. As a result, a continuous color change from blue to yellow could be expressed on films given the precise control of the surface plasmonic resonance phenomenon. Grazing-incidence small-angle scattering (GISAXS) analysis indicated that the sputtering power density had a significant effect on the size, distribution, and orientation of the Ag nanoclusters in the thin film. For low sputtering power densities, Ag nanoclusters were forming aggregations along the out-of-plane direction, but as the sputtering power density increased, the nanoclusters showed random distribution instead of large aggregates. We also demonstrated applications of Ag/PPFC nanocomposite thin films to a color filter, heat mirror, semi-transparent electrode, and electromagnetic shield. In addition, the fabrication of a large-area film (400 × 700 mm2) showed that the approach applies highly to industries.

Piezo-electret vibration sensors designed for acoustic-electric guitars

A piezo-electret vibration sensor designed for acoustic-electric guitars is evaluated. A piezo-electret, which is a cellular polypropylene electret film, is laminated with a 150-μm-thick polyethylene terephthalate (PET) film to achieve sufficient durability for general use. Additionally, a 10-μm-thick silver electrode is printed on the top surface as a shield electrode. This electrode adds a mass of only 63 mg to the sensor. The sensor is attached to the soundboard of a guitar body. An impact force is applied to the top of the saddle of the guitar body. The output voltage of the sensor owing to the vibration of the soundboard is measured by a voltage follower and an FFT analyzer. Conventional sensors that use lead zirconate titanate (PZT) ceramics are also tested. The results show that only the piezo-electret sensor detects the vibration of the soundboard over a wide frequency range up to 10 kHz. The time response of the sensor also corresponds to the vibration of the soundboard. However, the output voltage of the sensor is 1/10 to 1/100 of that of the PZT sensors. The effective d 33 value of the sensor is 1.58 pC/N at 1 kHz. The value is only 1/280 of the apparent d 33 value of the piezo-electret, owing to an increase in the effective elastic modulus in the thickness direction caused by lamination with the PET film.

A novel method to study the property of the interface between silicone rubber and fiber reinforced plastic

In this paper, a four-electrode system is developed to determine the interface resistivity of the specially made specimens containing an interface between silicone rubber (SR) film and a fiber reinforced plastics (FRP) substrate. Both simulation and experiment show that the shield electrodes can successfully shield a considerably part of the bulk current. With the shield electrodes, the current flowing through the interface can be obtained and the interface resistivity is calculated. The influence of liquid permeation of SR as well as the recovery process on the interface resistivity is studied. The results show that interface resistivity is a sensitive electrical parameter reflecting the interface status and the newly-proposed test method can provide a means of evaluating the interface between the SR housing and FRP rod in a composite insulator.

Optimization of metal inert gas-welded aluminium 6061 pipe parameters using analysis of variance and grey relational analysis

It is an underlying fact for the case of the joining process especially welding to have optimized parameters in order to achieve joints with outstanding mechanical characteristics. In the current work, aluminium 6061 pipes were welded using gas metal arc welding process with appropriate ER 4043 electrode and argon shielding gas. Optimum welding parameters (namely, current, voltage and travel speed) are investigated using analysis of variance ANOVA and grey relational analysis GRA statistical approaches. High tensile strength and low corrosion rate were set as required characteristics of quality welds. Since there are two responses and two objectives, multiple-criteria decision-making approach—GRA, and ANOVA are performed. Optimal parameters from these statistical approaches are converged to 110 A, 19 V and 3 cm/min, respectively. It is deduced from this study that the optimal parameters are convergent irrespective of the two used techniques for the investigated experimental data.

Penetration Shape Variations Based on Electrode Tip Angles and Shield Gas Changes in TIG Welding

Penetration Shape Variations Based on Electrode Tip Angles and Shield Gas Changes in TIG Welding

Stress analysis of shielding electrode in chip with pressure sensor embedded in accelerometer

PurposeAnalysis of the thermal effects during the packaging process or in the actual operating environment is necessary to develop small monolithic integrated sensing chips with heterogeneous integration. The use of multiple layers and various materials in monolithic integrated sensing chips addresses the coefficient of thermal expansion (CTE) mismatch issue. The purpose of this study is to focus on the residual stress analysis of the shielding electrode, which is a metal film that prevents pull-in of proof-mass during anodic bonding in microelectromechanical system (MEMS) chips with pressure sensors embedded in an accelerometer.Design/methodology/approachThe finite element model of the chip was built by the commercial software ANSYS, and the residual stress was evaluated during the die attachment process for the shielding electrode. Various shielding electrode materials and a proposed design with a keep-out zone to reduce the residual stress are discussed, with a focus on the relationship between the geometric parameters of the chip and the residual stress for copper shielding electrodes of different thicknesses.FindingsThe results of the finite element analysis showed that the use of polysilicon as a shielding electrode in the proposed design generated the lowest residual stress because of its low CTE. The maximum stresses in both of in-plane and out-of-plane directions in the finite element model were reduced by keep-out zone design for the proposed design of the copper shielding electrode, and had 11 times reduction in out-of-plane direction especially, according to the nonlinear analysis as the stress concentration point in the shielding electrode moved. Moreover, the design with a thinner shielding electrode, thinner glass substrate and higher CTE of the glass substrate also lowered the maximum von Mises stress. On the other hand, the stress level during the operating temperature, without considering residual stress, overestimated up to five times in the proposed design.Originality/valueIn this study, valuable suggestions are proposed for the design of chips with pressure sensors embedded in accelerometers.

Electrostatic design and conditioning of a triple point junction shield for a -200 kV DC high voltage photogun.

Nuclear physics experiments performed at the Continuous Electron Beam Accelerator Facility (CEBAF) at the Jefferson Lab require a DC high voltage photogun to generate polarized electron beams from GaAs photocathodes. The photogun uses a tapered ceramic insulator that extends into the vacuum chamber and mechanically holds the cathode electrode. Increasing the operating voltage from nominal -130 kV to -200 kV will provide lower beam emittance, better transmission through injector apertures, and improved photocathode lifetime. This desire to increase the photogun operating voltage led to the design of a triple-point-junction shield electrode which minimizes the electric field at the delicate insulator-metal-vacuum interface and linearizes the potential across the insulator, thus reducing the risk of arcing along the ceramic insulator. This work describes the results obtained using COMSOL® electrostatic-field simulation software and presents the high voltage conditioning results of the upgraded -200 kV CEBAF photogun.