Silver Tin Oxide Research Articles

Research on the influence of different organizational structures on the electrical life of sealed relays

Abstract A sealed relay is a type of power relay mainly used in fields with harsh environments, low noise requirements, or high-reliability requirements. It is used in scenarios such as vehicle loads, household appliances, industrial control, and motors. At the same time, when the input meets certain specified conditions, it is a device that can generate a jump in one or more electrical output circuits, playing a role in controlling the on/off current of the connected circuit. Power relays have been widely used in various fields due to their small size, low noise, and low power consumption advantages. This article mainly studies the electrical parameters such as arc energy, arc time, welding force, and contact burning principle of silver tin oxide electrical contact materials produced by different processes, providing a reference for the development of electrical contact materials.

In situ observation and understanding of the arc erosion behavior of electrical contact materials

Abstract Arc erosion studies are carried out on electrical contact materials in the switching current experiment. A test rig is developed to capture the 2-D image and the 3-D profile of eroded silver tin oxide electrical contact material in situ. Image processing algorithms are specially presented to accurately recognize the features of erosion region. The initial small patch of erosion traces gradually evolves into the deep crater with the increment of switching cycle enabling a study of the arc erosion behavior. 2-D image, 3-D profile, and micro surface morphologies of the eroded contacts are analyzed and then related to the extent of erosion. The results show that the evolution process of central erosion region could be divided into the enlargement in breadth of contact surface and the extension in depth of contact profile. The end result of arc erosion is the net loss of contact material, which would lead to the substantial reduction of contact force and potential electrical contact instability.

Determination of the Power Balance for Thin Ag–SnO₂ Electrodes Submitted to an Electric Arc Based on IR Thermography

The objective of the work presented here is to estimate the characteristics of the power balance, i.e., the power and the surface power density that the electric arc brings to silver–tin oxide (Ag–SnO2) electrodes. This work is first based on an experimental study carried out using an IR camera with which we measured the temperature in a zone close to the area impacted by the arc, but not flashed by it. In a second step, the temperature distributions obtained are compared with the results of a numerical model of the electrode heating. The model input parameters are the power <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$P$ </tex-math></inline-formula> and the surface power density <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Q$ </tex-math></inline-formula> . Solving this inverse problem thus makes it possible to estimate the values of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$P$ </tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$Q$ </tex-math></inline-formula> leading to measured and calculated heating (temperature distribution) that are as similar as possible. Such a method has been applied for Ag–SnO2 cathodes and anodes and for various intensities of the arc current in a range of 80–200 A.

Biosynthesis of highly porous Ag/Bi/SnO2 nanohybrid material using seeds extract of Caesalpinia bonduc and their photocatalytic activity

In the current study, Tin oxide (SnO2), Silver–Tin oxide (Ag–SnO2), and Ag–Bi–SnO2 nanoparticles (NPs) were successfully synthesized using methanolic seed extracts of Caesalpinia bonduc (C.bonduc) plants. The NPS were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), Surface area analysis (SAA), energy dispersive X-ray (EDX) analysis, and Fourier transmission infrared (FTIR). The synthesized photocatalyst's surface area was 210, 235, and 238 m2/g for SnO2 and Ag–SnO2, and Ag–Bi–SnO2, respectively. The catalyst showed excellent activity for the degradation of MB dye in an aqueous medium. The results confirmed that the Ag–Bi–SnO2 exhibited 94% degradation of dye compared to Ag–SnO2 (90%) and SnO2(80%) under the same reaction conditions. Adding Ag and bismuth can also increase the degradation mechanism by preventing recombining electron-hole pairs. The report is novel, as no report to date has been published for the synthesis of Ag–Bi–SnO2, Ag–SnO2, and SnO2 NPs synthesized by C. bonduc seed extract; the procedure is simple, cheaper, and non-toxic compared to other methods employed for the synthesis of NPs. Eley-Rideal (ER) type of reaction mechanism was found to follow the degradation of MB dye in an aqueous medium.

Optimizing the thermoelectric properties of thermally evaporated AgSnO2 thin films by post growth annealing process

In this manuscript, we have studied the thermoelectric properties of Silver Tin Oxide thin films deposited by thermal evaporation method. Tube furnace was used to deposit thin films on silicon (100) substrate by evaporating a mixture of Silver (Ag) and Tin (Sn) having (1:1) ratio. The experimental conditions were set as: distance from source to substrate (5 cm), Evaporation temperature inside the tube furnace (1000 °C), flow rate of oxygen gas (120sccm) and evaporation time for deposition was set as 40 min. Furthermore, diffusion of oxygen and mobility of charge carriers was controlled by annealing the samples at various temperatures after successful growth. We have observed that the value of Seebeck coefficient was increased from 242 to 630 µV/oC by increasing the annealing temperature from 600 to 900 ° C. This behavior is due the fact that increasing annealing temperature causes the mobility of charge carriers increased due to which simultaneous enhancement in Seebeck coefficient and electrical conductivity is observed. The enhancement in the carrier mobility was demonstrated by the fact that extra oxygen atoms resulted in the generation of grain boundaries defects which block the slow moving carriers and only fast moving electrons are able to reach cold end of sample. XRD and Raman spectroscopy results confirmed the hexagonal structure of AgSnO2. XRD data further confirmed the degradation of crystal quality due to increase in annealing temperature. The morphology of as grown and annealed samples was observed with the help of SEM.

Contact welding strength measurement for metal electrode materials conducting inrush electrical current.

Contact welding is considered the major failure mechanism for electromechanical switch applications. There has been increasing demand to research the measurement method to characterize the anti-welding ability of metal electrode materials. In this paper, the contact welding phenomenon of closed electrodes is made to reoccur by using our novel designed test rig. The welding strength and welding area of typical electrode materials, including silver, copper, silver tin oxide, and silver nickel alloy, are explicitly measured and compared. In addition, the effects of electrical current and mechanical load force on welding strength and welding trace are presented. The calculation method of the threshold welding current is introduced for elastic contact situation in low current switching devices.

Influence of process parameters on the formation and quality of joining zones during induction brazing

Contact materials for electrical switch gears are widely used for connecting and disconnecting electric circuits. These contacts are two component systems, where the contact tips are brazed to the carriers prior to installation. The contacts used in the present work is a 3 layered sandwich structure consisting of a silver-tin oxide (Ag-SnO2) layer, a silver (Ag) inter-layer and a thin layer of the braze. The carrier itself is copper (Cu) - plated steel. The brazing process is accomplished by a high frequency inductive heating process. By varying the brazing parameters, namely, temperature and time, their influence on joint formation is investigated. The brazing joint of the contact tips were characterized by microscopy (light and electron microscopy) and physical analytical techniques (energy dispersive X-ray analysis. The mechanical characteristics were determined with Vickers micro-hardness. Investigations indicated that, comparatively, the variations in temperature had a greater influence on joint zone formation and their mechanical properties. It was further demonstrated that the extended hold times lead to a higher degree of joint zone filling due to a large reduction in pore volume fraction.

Flexible CPW fed transparent antenna for WLAN and sub‐6 GHz 5G applications

AbstractA transparent flexible co‐planar waveguide fed patch antenna using polyethylene terephthalate substrate is presented. The wideband high gain antenna having an overall dimension of 0.48λ × 0.64λ at the center frequency of 4.28 GHz is fabricated using a transparent sheet made up of Silver Tin Oxide (AgHT‐8). The performance of the proposed antenna is compared with four other nontransparent nonflexible and semitransparent flexible antennas. For the engineered design, patch geometry and feeding mechanism are kept constant whereas the substrate and patch materials are varied. Simulations are carried out using finite element method‐based full wave high‐frequency structure simulator after which the antennas are fabricated and tested. The proposed flexible transparent antenna has bandwidth in order of 40%, ranging from 3.89 to 5.9 GHz, with a notable gain over 3 dBi and efficiency greater than 80% for the entire frequency band. The bending conditions are also tested for the flexible transparent antenna which showed decent performance for sub‐6 GHz 5G and WLAN applications.

Dual band transparent antenna for wireless MIMO system applications

AbstractA dual‐band optically transparent antenna based on a slotted interconnected ring resonator as an efficient radiating element is proposed. The compact radiating element and partial ground plane are structured on a plexiglass substrate with Silver Tin Oxide as transparent conducting material. The radiation disadvantage of OTAs due to the low conductivity of conductive oxides has been overcome with the gain improvement technique of 2 × 1 antenna array design. The overall sizes of the proposed single element and 2 × 1 two element array antennas are λ/2.5 × λ/2.5 and λ/1.19 × λ/2.08 at the lower resonance frequency of 2.4 GHz, respectively. The operation bands of both OTA prototypes cover WLAN and WiMAX frequency bands with permissible bandwidth and sufficient gain therefore the 2 × 1 antenna array is utilized as one of two dual‐band antennas of a 2 × 2 MIMO transceiver system for WLAN and WiMAX band operations.

Effect of Electrical Load on Contact Welding Failure of Silver Tin Oxide Material Used in DC Electromechanical Relays

In order to clarify the contact welding failure mechanism of DC electromagnetic relay, a series of electrical endurance tests are carried out with the use of silver tin oxide material under resistive and capacitive load conditions. The typical waveforms of contact voltage and contact current during making and breaking resistive load and capacitive load (load capacitance of 1mF, 1.5mF, 2mF and 2.5mF) are obtained by the designed model switch. Further, the variations of sensitive electrical parameters such as bounce energy, contact resistance, static contact force and break arc energy during electrical endurance test are analyzed explicitly. It is found that the variations in sensitive electrical parameters is closely related to the electrical load type. In particular, under the capacitive load conditions, the sharp increase of each sensitive electrical parameter in the end of lifetime prognosticates the dynamic welding failure of silver tin oxide contact material. Finally, with the help of SEM (Scanning Electron Microscope) pictures of failed contacts, the surface erosion features of contact materials are mainly determined by the competition between the cathode arc and the anode arc. And the material transfer and distribution are the root reason for the contact welding failure of DC electromechanical relays.

Study on Switching Characteristics and Associated Degradation Mechanism of Contact Material Under Capacitive Load

Electrical lifetime and relative dynamic welding failure mechanisms of an electromechanical relay for a capacitive load are interesting topics in the area of switching devices and contact materials. In this paper, a silver tin oxide contact material has been tested with a capacitive load by using our designed novel model switch. The typical waveforms of contact current and contact voltage at making and breaking are presented. Furthermore, the variations in bounce energy, static contact force, dynamic contact force, arc energy, and contact resistance as a function of operation cycles are plotted and analyzed explicitly. In particular, the intermittent long-duration arcing phenomena during breaking are observed and explained with the variations in local contact asperities. Based on the collected sensitive parameters, an associated physical degradation mechanism of contact materials under the capacitive load is proposed.

Parameter Characterization in Processing of Silver – Aluminum Based Electrical Contact Materials

AbstractAn electrical contractor is one which plays significant role in day todays life in industries as well as in home appliances. In current scenario the materials for conducting purpose has an overwhelming research capability. Now a day the silver based electrical contact composite material have provided the potential applications in aerospace and automobile industries. Among silver based contact material the silver cadmium oxide and silver tin oxide plays a vital role in fabrication of electrical contactors. In this research an attempt has been made to study the influence of adding Aluminum with silver based electrical contact composite materials by two different processing routes namely stir-casting and powder metallurgy. Silver and aluminum matrix plays a virtual role in composite world owing to their highest conductivity. Optimum parameters were identified for attaining the maximum properties such as conductivity, hardness, density, and porosity of composition. By this better conducting property and mechanical property of the electrical contact can be improved by this system. Thus a screening test has be conducted with addition of Al with silver tin oxide compositions hence this paper aims to process the aluminum - silver based electrical contact materials by stir casting processing and powder metallurgy route and compare the results obtained.

Facile synthesis of silver-tin oxide electrical contact materials by in-situ decomposition of a uniform mixture precursor

A uniform mixture precursor containing Ag2O and Ag2SnO3 was synthesized via a facile ion exchange reaction method. The influence of pH value on composition and precipitation rate of the precursor was investigated systematically. The Ag-SnO2 composite powder was obtained by decomposition of the precursor at 600°C, and uniform mixing of elements was inherited from the precursor and fresh and intimate Ag-SnO2 interfaces were created. The Ag-SnO2 electrical contact material was prepared using this composite powder by hot-pressing method. It was found that nano-sized SnO2 particles (about 20.6 nm) are homogeneously dispersed in the Ag-matrix. The as-prepared Ag-SnO2 electrical contact material shows excellent performances, such as high hardness (154 MPa), high density (9.90 g/cm3) and good electrical conductivity (72.24%IACS).

Fabrication of Ag–SnO2 Contact Materials from Gas‐Atomized Ag–Sn Powder Using Combined Oxidation and Ball‐Milling Process

Silver–tin oxide (Ag–SnO2) is considered to be an effective alternative to silver–cadmium oxide (Ag–CdO), which is carcinogenic and, therefore, toxic to the human body. In this study, Ag–SnO2 powder was prepared through a combined oxidation and ball‐milling process using gas‐atomized Ag–Sn powder. During oxidation, the Ag3Sn phase disappeared at 800°C and SnO2 was formed without Ag oxidation; this SnO2 formed a layer structure that covered the Ag matrix. The thickness of the oxide layer increased after the composite was subjected to a second oxidation process. Owing to the resultant core (Ag)‐shell (SnO2) structure, the electrical conductivity of the fabricated composite was considerably lower than that of commercially available materials. However, the electrical conductivity increased remarkably after ball milling of the samples, which allowed the SnO2 surface layer to be peeled off and crushed. Following high‐pressure magnetic pulsed compaction, the SnO2 was found to be homogeneously distributed in the Ag matrix, which exhibited a lamellar structure.

Preparation of Electrical Contact Materials by Cold Gas-Spray

Abstract This work shows the feasibility of cold gas-spray technique for the manufacturing of industrial electrical contact materials. Microstructure and mechanical properties of the material were investigated using optical microscopy, scanning electron microscopy, hardness test and shearing test. Results show that the bonding strength of the material is determined by the hardness of substrates. High hardness results in low bonding strength. Bonding strength of AgSnO 2 sprayed onto aluminum is the best, followed by copper and brass. The bonding strength of silver graphite is not as good as that of silver tin-oxide. The most appropriate particle size is 20 μm for a bulk particle according to the optimization.

The effects of citric acid on the synthesis and performance of silver–tin oxide electrical contact materials

A sol–gel auto-combustion method was developed to synthesize the Ag–SnO2 composite powders, which were then used as the starting material to prepare Ag–SnO2 electrical contact materials by hot pressing. It was found that citric acid strongly influences the thermal behaviors, phase evolution, morphology and composition distribution of the Ag–SnO2 composite powders. During the synthesis of Ag–SnO2 composite powders, citric acid can facilitate the formation of sol solution, lower the energy required for the decomposition of dry gel, and reduce the agglomeration of particles. Besides, a comparatively high molar ratio of citric acid to metal ions prevents effectively the occurrence of composition segregation in the Ag–SnO2 electrical contact materials. Therefore, the prepared Ag–SnO2 electrical contact materials have good performances in density, hardness and electric conductivity.

Optimization of Transmission Lost for Energy Saving Glass with Different Sheet Resistance Values

Recently, energy saving glass is commonly applied in the modern engineered building. This is due to its advantages of keeping the heat inside the building in winter while rejecting the heat when in summer. The typical energy saving glass is made by applying a very thin metallic oxide such as silver oxide or tin oxide on one side of the float glass. But at the same time, it has the disadvantages of attenuates useful microwave frequencies that ranging from 0.8 2.2 GHz. The examples of the microwave frequency at this range are GSM mobile signal, GPS and personal communication. Frequency selective surface (FSS) has been introduced to overcome this drawback of energy saving glass. In this study, the transmission of the microwave signal is observed through the simulation using Computer Simulation Technology Microwave Studio. Bandpass frequency selective surface of cross dipole shape is used for the simulation. In the simulation, conductivity and electrical properties of glass and metal oxide thin film are important. The microwave transmission was evaluated at various sheet resistance of metal oxide thin film. The results show that the minimum transmission lost increased with the ohmic resistance increased. On the other hand, the peak frequency at various sheet resistance shows constant value at around 1.25-1.30 GHz. The full width half maximum of the microwave transmission increases with the sheet resistance value. The results suggest that FSS structured metal oxide thin film with lowest sheet resistance transmits more signal in the range for GSM phone signal.

Properties Enhancement of an Eco-Friendly Electrical Contact Material by Silver Nanoparticles Addition

Silver-tin oxide electrical contact material with 10 wt pct stannic oxide and balance nanosized and micronsized silver was developed successfully. Stannic oxide particles chemically coated by a layer of silver nanospheres are homogeneously dispersed in a silver microcrystalline matrix made by chemical synthesis. The material processed by pressing-sintering-repressing exhibited enhanced properties: density: 97.1 to 97.9 pct relative density, Vickers hardness: 103 to 115, electrical conductivity: 65 to 69 pct IACS, volumetric shrinkage: 28.9 to 30.9 pct, and a very fine and uniform microstructure.

Synthesis of silver tin oxide nanocomposite powders via chemical coprecipitation method

Abstract A nanocomposite powder Ag-SnO2 was produced by the chemical coprecipitation technique using Sn element, SnCl2.2H2O and silver nitrate as starting materials and carbonate solutions as precipitating agents. The effect of the chlorine ion, ionic strength and supersaturation were investigated for nanopowder using X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and X-ray mapping. The fine and uniformly dispersed microstructure are attained by using coprecipitation method. Higher ionic strength leads to lower particle size of nanocomposite. The undesirable chlorine ion, which leads to instability in contact surface, is eliminated by replacing SnCl2.2H2O instead of Sn element as starting material. Also the degree of agglomeration decreases with this change. The results show that the increasing in the supersaturation of environment enhances the nucleation. So it causes a reduction in the nanocomposite particle size to 50%.

Mechanism Study on Forming Flake Silver Tin-Oxide Composite Powder

Silver powder and silver-tin oxide composite powder were synthesized by hydrothermal method. The powders were characterized by XRD and SEM. The results show that there are macroscopic appearance and microscopic structure differences between two kinds of powders. Silver powder is gray and spherical particles with 3μm diameter, and silver-tin oxide composite powder is black ash and mainly flake particles about 0.3μm in thickness. Silver crystal in silver tin-oxide composite powder is preferentially oriented in the (111) crystal plane and its oriented index is 2.581. However oriented index of silver crystal in silver powder is 1.048 which shows the crystal isn’t preferentially oriented in the (111) crystal plane. That crystal lattice parameter of silver crystal in silver tin oxide composite powder is 0.409 34 nm larger than 0.408 68 nm of silver powder. The mechanism analysis shows that the hydrogen bonds among Sn(OH)62- and Ag(SO3)23- complexes are inhere factor which result in the formation of flake silver tin-oxide composite powder.