Electrostatic Discharge Research Articles

Cold Nitrogen Plasma: A Groundbreaking Eco-Friendly Technique for the Surface Modification of Activated Carbon Aimed at Elevating Its Carbon Dioxide Adsorption Capacity

The commercially available activated carbon was modified using barrier and spark discharge low-temperature nitrogen plasma treatment. The samples were investigated using nitrogen sorption at a temperature of −196 °C, XRD, SEM, and FTIR methods, and elemental analysis. The nitrogen content on the surface was increased, but other properties, such as specific surface area, total pore volume, pseudocrystallite height, and pseudocrystallite width, remained unchanged. The activated carbons after nitrogen plasma treatment indicated higher CO2 adsorption than the pristine ones. Since the investigated materials only differed in their nitrogen content, it has been unequivocally demonstrated that the increased presence of nitrogen is responsible for the enhanced adsorption of CO2. The low-temperature nitrogen plasma treatment of activated carbon is a promising method for enhancing CO2 capture.

Decreasing the electrostatic discharge generated from friction of polyester and polyamide sing carbon fiber

AbstractThe present work discusses the voltage difference as a measure for electrostatic charge generated from the contact‐separation and sliding of polymeric textiles on polyamide textile. It is proposed to blend polyester by carbon fiber to decrease the electrostatic charge generated on the contact surfaces. Because polyester acquires a negative charge and polyamide gains a positive one, carbon fiber is proposed to conduct the negative electrostatic charge from polyester to polyamide and conducts the positive one from polyamide to polyester, so that the resultant electrostatic charge decreased. The effect of carbon fiber to decrease the electrostatic charge depends on its area of contact, interaction, and distribution with polyester. Polyester double weaved by carbon fiber showed the lowest voltage. Based on those observations, it can be recommended to use double weaves of carbon fiber with polyester. The reduction in voltage was relatively lower for braided polyester by carbon fiber than that detected for double‐weaved polyester by carbon fiber.

Effect of electrolyte pH value on microstructure and corrosion resistance of black MAO coating on 6063 aluminum alloy

Black micro-arc oxidation (MAO) coatings were obtained on the surface of 6063 aluminum alloy by using the MAO technique in silicate electrolyte with colorant NH4VO3. The work aimed to study the effect of adjusting the electrolyte pH (pH10, pH11, pH12, and pH13) on the microstructure, mechanical properties, and corrosion resistance of black MAO coatings on 6063 aluminum alloy. The experimental results showed that the electrolyte pH had an important effect on the macroscopic morphology of the MAO coatings. As the electrolyte pH value increased, the process voltage of the sample decreased, the duration of the anodic oxidation stage and the spark discharge stage were shortened, while the duration of the micro arc oxidation stage was prolonged. Reasonable adjustment of the electrolyte pH could reduce the poriness and defects of the coatings, decrease the surface roughness of the coatings, and improve the quality and wear resistance of the coatings. The corrosion resistance of the black MAO coating obtained in the electrolyte with pH12 was superior and the corrosion current density was only 3.207×10−7 A/cm2. The immersion corrosion test further demonstrated the same results of corrosion resistance.

Dynamics of high-speed electrical tree growth in electron-irradiated polymethyl methacrylate.

Dielectric materials are foundational to our modern-day communications, defense, and commerce needs. Although dielectric breakdown is a primary cause of failure of these systems, we do not fully understand this process. We analyzed the dielectric breakdown channel propagation dynamics of two distinct types of electrical trees. One type of these electrical trees has not been formally classified. We observed the propagation speed of this electrical tree type to exceed 10 million meters per second. These results identify substantial gaps in the understanding of dielectric breakdown, and filling these gaps is paramount to the design and engineering of dielectric materials that are less susceptible to electrostatic discharge failure.

Anticancer transmission effects induced by hybrid plasma bubble-activated medium

As an indirect application of cold atmospheric plasma, the use of plasma-activated solutions has recently attracted significant attention for intracavity tumor perfusion therapy. Here, an underwater plasma-bubble reactor with three discharge modes was applied to activate a cell culture medium, with the aim of inhibiting the growth of bladder cancer T24 cells in vitro. The results showed that although the reactive species in cell culture medium generated by the underwater bubble plasma varied between the dielectric barrier discharge (DBD) mode, spark mode, and hybrid mode, the plasma-activated cell culture medium (PAM) corresponding to all three discharge modes effectively decreased the viability of T24 cells. However, after co-culturing the PAM-pretreated T24 cells with normal T24 cells, it was observed that normal T24 cells were not affected by either the DBD or spark mode; however, the hybrid mode PAM-pretreated T24 cells further induced inactivation and apoptosis of normal T24 cells. Further studies suggested that the aqueous reactive species generated by the underwater bubble plasma in hybrid mode not only induced the apoptosis of T24 cells directly but also triggered PAM-pretreated T24 cell-derived exosome-mediated anticancer activity toward cancer cells. These results may provide a strategy for enhancing the anticancer extent and effect of PAM as well as advancing its clinical application.

Formation of diffuse and spark discharges between two needle electrodes with the scattering of particles

The development of a nanosecond discharge in a pin-to-pin gap filled with air at atmospheric pressure has been studied with high temporal and spatial resolutions from a breakdown start to the spark decay. Positive and negative nanosecond voltage pulses with an amplitude of tens of kilovolts were applied. Time-resolved images of the discharge development were taken with a four-channel Intensified Charge Coupled Device (ICCD) camera. The minimum delay between the camera channels could be as short as ≈ 0.1 ns. This made it possible to study the gap breakdown process with subnanosecond resolution. It was observed that a wide-diameter streamer develops from the high-voltage pointed electrode. The ionization processes near the grounded pin electrode started when the streamer crossed half of the gap. After bridging the gap by the streamer, a diffuse discharge was formed. The development of spark leaders from bright spots on the surface of the pointed electrodes was observed at the next stage. It was found that the rate of development of the spark leader is an order of magnitude lower than that of the wide-diameter streamer. Long thin luminous tracks were observed against the background of a discharge plasma glow. It has been established that the tracks are adjacent to brightly glowing spots on the electrodes and are associated with the flight of small particles.

Centimeter-level 2D ultra-small interdigital sensor for ESD detection of spacecraft

The spacecraft in geosynchronous orbit interacts with the space plasma environment, which is prone to electrostatic discharge and affects the safe operation of the spacecraft. In order to realize simple, accurate and reliable electrostatic discharge detection in space environment, based on the energy spectrum characteristics of spacecraft electrostatic discharge electromagnetic radiation electromagnetic pulse and the electromagnetic pulse sensing principle of interdigital electrode, a centimeter-level two-dimensional planar ultra-small interdigital sensor with a size of only 4 cm × 3 cm × 0.01 cm is developed. The impedance matching circuit is established to greatly improve the transmission efficiency of electromagnetic pulse, which is 59.34 % higher than that before the matching circuit is added. Finally, a spacecraft vacuum electrostatic discharge simulation experiment platform is built to test the frequency response characteristics of the sensor. The results show that the frequency response characteristics of the electromagnetic pulse signal perceived by the sensor developed in this paper are consistent with the main frequency characteristics of the spacecraft electrostatic discharge radiation electromagnetic pulse energy spectrum, which can be used for spacecraft electrostatic discharge detection in space environment.

Low Current Density Cathode Plasma Electrolytic Deposition of Aluminum Alloy Based on a Bipolar Pulse Power Supply

The present paper reported a novel bipolar-pulse cathodic plasma electrolytic deposition (BP-CPED) technique with a low current density. This newly developed CPED technique can break down the barriers of the existing CPED technique with higher current density. In this report, ceramic coatings were successfully prepared on aluminum alloy via the BP-CPED technique in an aqueous carbamide-based electrolyte. Data recording results in the reacting process show that there is the current density of the cathode below 0.15 A/cm2 and that of the anode below 0.035 A/cm2, which approximately reaches the level of conventional MAO technique. Interestingly, the addition of PEG into the electrolyte can further reduce the current density and effectively improve the coating quality. The kinetic of the BP-CPED process was discussed based on the evolution of current density/voltage-time curves and spark discharge phenomena. SEM observations illustrate that BP-CPED coatings possess a typical porous-surface feature. XRD analysis indicates that the coating was mainly composed of Al2O3 and Al4C3. Al2O3/Al4C3/ZrO2 composite coatings fabricated after Zr-doping reflected the successful Zr-incorporation into the coating, which demonstrated that the BP-CPED technique can be used to design the coating composition by the doping modification. The direct pull-off and thermal shock tests confirmed that new BP-CPED coatings obtained under the cathodic plasma discharge have excellent bonding strength. It is possible that this novel BP-CPED technique can provide a promising choice in developing the large-area CPED surface treatment for the industrial application.

Characterization of Some Functional Polymeric Composites in a Synergistic Regime of Protection at Electromagnetic Shielding and Electrostatic Transfer

The paper presents the characterization of 5 polymer composite materials with a poly-propylene (PP) matrix obtained with different (mass) concentrations of strontium ferrite (Fe12SrO19) reinforcement that have synergistic protective properties against electrostatic discharges (ESD) and electromagnetic impulses (EMI). These types of composites can be used to protect electronic equipment. To this purpose, suitable polymer composites were developed using SrFe12O19 type filler in two forms (powder and concentrate). The weight ratio of the PP/SrFe12O19 composites obtained by the extrusion process and injection from the melt is 75/25 and 70/30. The characterization of these composite materials consisted of carrying out some physico-chemical tests to determine the hydrostatic density and the resistance to the action of water, as well as FTIR, UV-Vis analyzes and dielectric, magnetic and functional tests to identify the simultaneous protection performance at electromagnetic shielding and electrostatic discharges, which can occur in the electro-technical, electronics and automotive industries. It is also found that all composite materials presented reflection shielding properties (SER) in the range: -71.5 dB...to -56.7 dB, indicating very low absorption shielding. The best performing material was the PP/SrFe12O19 powder composite with a weight ratio of 70/30. At the same time, EDS tests were also carried out on these materials. For these applications, the surface resistance Rs and the point-to-point resistance Rp were tested. Recommended composites for simultaneous EMI and sensitivity to electrostatic discharges (ESD) functionality, in order of their performance, are M2 (with 30% ferrite powder) and M1 (with 25% ferrite powder). M4 composite (with 30% ferrite powder concentrate) can also be used at the limit. Following the research carried out, the obtained results recommend the composite with promising simultaneous operations as M2 (with 30% ferrite powder). The element of originality consists of obtaining polymer composites with simultaneous properties of protection against electromagnetic impulses and electrostatic discharges.

Machine learning for parameters diagnosis of spark discharge by electro-acoustic signal

Discharge plasma parameter measurement is a key focus in low-temperature plasma research. Traditional diagnostics often require costly equipment, whereas electro-acoustic signals provide a rich, non-invasive, and less complex source of discharge information. This study harnesses machine learning to decode these signals. It establishes links between electro-acoustic signals and gas discharge parameters, such as power and distance, thus streamlining the prediction process. By building a spark discharge platform to collect electro-acoustic signals and implementing a series of acoustic signal processing techniques, the Mel-Frequency Cepstral Coefficients (MFCCs) of the acoustic signals are extracted to construct the predictors. Three machine learning models (Linear Regression, k-Nearest Neighbors, and Random Forest) are introduced and applied to the predictors to achieve real-time rapid diagnostic measurement of typical spark discharge power and discharge distance. All models display impressive performance in prediction precision and fitting abilities. Among them, the k-Nearest Neighbors model shows the best performance on discharge power prediction with the lowest mean square error (MSE = 0.00571) and the highest -squared value ( ). The experimental results show that the relationship between the electro-acoustic signal and the gas discharge power and distance can be effectively constructed based on the machine learning algorithm, which provides a new idea and basis for the online monitoring and real-time diagnosis of plasma parameters.

A study of the effects on human electrostatic discharge current waveform verification

A study of the effects on human electrostatic discharge current waveform verification

Influence of non-valve metal phase on growth behavior and performance of PEO coating on Mg–Zn–Mn alloys with high Mn content

The influence of pure metal phases (precipitation or reinforcement phases) on the PEO discharge and coating growth in Mg alloys remains underexplored. This study investigated the effects of the α-Mn phase on voltage evolution, coating morphology, phase composition, and corrosion resistance by subjecting Mg–4Zn-xMn (x = 0, 0.6, 1.2, 2.4 wt%) alloys to PEO treatment in alkaline silicate-based electrolyte. Results indicate that the presence of α-Mn does not prevent spark discharge. However, an increase in α-Mn content leads to a downward shift in the voltage-time curve. The α-Mn phase significantly slows down the voltage ascent rate and prolongs the duration of Stages I to III of PEO process. Electrochemical oxidation of the surrounding Mg matrix by the α-Mn phase induces the formation of pits and porous local morphologies, exacerbating coating unevenness. With the increasing in Mn content, the thickness and porosity of PEO coatings gradually decrease for the same treatment time. The coated Mg–4Zn-1.2Mn alloy exhibits the highest corrosion resistance. The differences in oxidizability between the α-Mn phase and the Mg matrix, as well as the stability and dielectric properties of the oxide products may be the underlying reasons for these effects. Despite Mn oxides' instability under alkaline conditions at high potentials, reaction products with the electrolyte offset this drawback. This study enhances understanding of pure metal phases' influence on Mg alloy PEO and contributes to research on PEO processes for Mg-based materials containing pure metal phases.

Identification of the energy parameters of an electrohydroimpulse plant for the production of valuable components from organic raw materials

The paper presents the results of experimental studies on the developed bone degreasing stand. The object of the study is the production of valuable components from organic raw materials. Fractions of cattle crushed to the size of 2.5 mm, 5.2 mm and 10.5 mm were used to identify the effective mode of operation of an electrohydroimpulse installation. Physical and chemical methods of fat extraction are currently not relevant from the point of view of economy, due to environmental damage and labor intensity. In this regard, new effective methods of extracting fat from bone mass are needed. Therefore, the proposed method of extracting fat by spark discharge is an actual and alternative method for today. During the study, an acceptable temperature regime for fat production was obtained. Next, a laboratory stand was assembled, with which you can degrease the bone mass without changing the properties of fat. Experimental studies show that with an increase in the capacity of the capacitor bank in energy storage devices and the length of the discharge gap, the bone degreasing process becomes more efficient. During the study, it was found that at a liquid temperature of 38 °C and a pulse voltage of 25 kV on a switching device of an electrohydroimpulse installation, the degree of fat extraction increases without destroying the morphological structure of bone mass. Using the hexane extraction reaction, we determined the efficiency of fat extraction at a temperature of 38 °C, at which the fat mass from the bones is effectively broken down, and using the UV-1800 spectrophotometer, we determined the amount of protein in the bones before and after treatment. The study also showed that with a capacitor bank capacity of 0.5 uF, crushed to a fraction of 10.5 mm of pelvic bone, the separated fat is 18.7 %, and with constant grinding of the capacitor bank to a fraction of 2.5 mm – 19.4 %

Strong and antistatic biomass adhesive for wood-based composites with electrostatic discharge protection function

Soybean protein adhesive, as an aldehyde-free biomass adhesive, has gained significant attention as an environmentally friendly material in recent years. It not only aligns with the objectives of the double carbon strategy but also contributes to the environmental protection strategy of reducing carbon emissions. And the functional modification of soybean protein adhesive and its wood composite hold great importance in expanding its application domains and meeting specialized requirements. This research focused on developing a robust, antistatic adhesive derived from soy protein as an alternative to formaldehyde-based resins, which represents a critical path in the advancement of wood-based composites that are free from formaldehyde and possess functional properties. However, ensuring the bonding strength of soy protein adhesive while developing antistatic adhesives and their wood-based composite materials is of great research value and challenge. Inspired by the organic-inorganic hybrid structure, this study aimed to prepare a strong and durable soy protein adhesive with excellent mechanical strength and multifunctionality by using a self-synthesized crosslinking agent called AP and the loaded two-dimensional MXene, which was stabilized in a dispersion of nanocellulose (CNC). The dry and wet shear strength of the resulting adhesive increased by 103.8 % and 113.8 % to 2.21 MPa and 1.24 MPa, indicating the stable crosslinking structure formed in adhesive system by the covalent bond between self-synthesized crosslinking agent AP and the carboxyl groups on proteins, as well as the hydrogen bond interactions between C-M and the proteins. Furthermore, the adhesive exhibited significant antistatic and self-extinguishing properties, with the particleboard modified by adhesive SPI/C-M/AP having a resistivity of 9.212 × 1011 Ω cm. The resistivity decreased with increasing MXene content, providing potential applications for places such as school computer rooms and factory electronic equipment rooms. This breakthrough in multifunctional biomass-based adhesives and composite materials enriches the preparation of new types of biomaterials with antistatic and flame retardant properties.

EMC Research Efforts in the IEEJ Technical Committee and State‐of‐the‐Art Case Studies on ESD Found in its Technical Papers

Electrostatic discharge (ESD) has been known to cause electromagnetic noise against electronic equipment and devices even before the technical concept of electromagnetic compatibility (EMC) was established 68 years ago in the United States and 48 years ago in Japan, while the ESD still continues to be studied as one of the most significant issues that should be solved in EMC areas. This is largely because the underlying nature of ESD has yet to be essentially elucidated from an EMC perspective. On the other hand, as an academic research organization on EMC in Japan, a Technical Committee named ‘EMCJ’ on ‘Environmental Electromagnetic Engineering’ was founded in 1976 in both the Institute of Electrical Engineers of Japan (IEEJ) and the Institute of Electronics and Communication Engineers or the present IEICE (Institute of Electronics, Information and Communication Engineers) to address EMC concerns. Since then, the EMCJ has been jointly conducting EMC research activities under the IEICE as the nominating body and the IEEJ as the associative body, whereas the EMCJ of IEEJ was dissolved in 1999 to form a new Technical Committee on EMC (TC‐EMC) in order to deal with EMC issues appropriate to the IEEJ. In this review, to mark the 25th anniversary of the IEEJ Technical Committee on EMC (TC‐EMC) in 2024, the EMC research efforts and activities that the TC‐EMC has conducted over the past 25 years from January 2000 to March 2024 are surveyed from 1272 technical papers presented at the technical meetings. Furthermore, among the ESD issues identified in these technical papers, the latest case studies utilizing ‘spark resistance laws’ that allow the analysis of the initial behavior of sparks, in which a spark is the essence of ESD and is the key to open the door to elucidate the phenomenon, particularly from an EMC perspective, are reviewed. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC.

Analysis of Energy During Spark Discharge in Short Circuit of Capacitive Circuit

ABSTRACT In the explosive environments, the electrical sparks with short circuit of capacitor output will ignite the surrounding explosive medium, and the relationship between effective ignition energy, capacitance energy conversion rate, capacitor capacitance and capacitor terminal voltage is unclear. Based on the three stages of breakdown, discharge and attenuation of the discharge characteristic curve of capacitive circuit, this paper deduces the expressions of spark resistance and discharge current including voltage, capacitance and polar distance parameters. Based on the programmable micro-nano gap discharge experimental platform, experiments under different voltages and different capacitances were carried out. It is found that the theoretical voltage-current curve and spark energy conversion rate are in good agreement with the experimental fitting curve and spark energy conversion rate. And with the increase of capacitance or voltage, the peak current and discharge time increase, which leads to the increase of energy. The conversion rate of spark energy decreases with the increase of capacitance or voltage, and the conversion rate changes between 20% and 30%. The change of spark energy conversion rate is also related to spark resistance, and with the decrease of spark resistance, the spark energy conversion rate also decreases. This study can further understand the energy variation in the discharge gap and is of great significance for the research of intrinsically safe circuits.

Research on machining Technology of Electrospark-electrochemical Hybrid Energy Field with tungsten hole

The machining technology for tungsten hole faces considerable challenges. Electrical Discharge Machining (EDM), as a non-traditional machining technique, is widely applied due to its capability to process conductive materials. This technique is characterized by high precision metal processing, high material removal rate, and low tool wear rate. Molecular dynamics simulation technology is employed in this study to model the single pulse discharge process, with the aim of elucidating the erosion mechanism of different melting point metal materials in the melt pool during spark discharge and the effect of pressure difference inside and outside the melt pool. Moreover, for the efficient machining of tungsten materials, Electrospark-electrochemical Hybrid Energy Field Machining (ECEM) method is proposed, which is conducted under a certain conductivity salt solution. The simultaneous high-speed electric spark discharge and electrochemical action effectively promote the rapid formation of spark plasma discharge channels. Orthogonal experimental data and images are utilized in this paper to study the machining of tungsten micropores, with the effects of pulse width, pulse interval, peak current, and concentration of NaNO3 being analyzed, and the optimal machining parameters being determined.

Challenges: ESD Protection for Heterogeneously Integrated SoICs in Advanced Packaging

Electrostatic discharge (ESD) failure is a major reliability problem for all forms of microelectronics products. ESD protection is required for all integrated circuits (ICs). As dimension scaling-down approaches its physical limit, heterogeneous integration (HI) emerges as a main pathway towards the age beyond Moore’s Law to facilitate advanced microsystem chips with extreme performance and rich functionalities. Advanced packaging is a key requirement for HI-enabled integrated systems-on-chiplets (SoIC) that require robust ESD protection solutions. This article outlines key emerging technical challenges associated with smart future SoIC microsystem superchips in the context of advanced packaging technologies.

On-board equipment testing procedure for the effects of electrostatic discharges

On-board equipment testing procedure for the effects of electrostatic discharges

Spark-Discharge-Activated 3D-Printed Electrochemical Sensors.

3D printing technology is a tremendously powerful technology to fabricate electrochemical sensing devices. However, current conductive filaments are not aimed at electrochemical applications and therefore require intense activation protocols to unleash a suitable electrochemical performance. Current activation methods based on (electro)chemical activation (using strong alkaline solutions and organic solvents and/or electrochemical treatments) or combined approaches are time-consuming and require hazardous chemicals and dedicated operator intervention. Here, pioneering spark-discharge-activated 3D-printed electrodes were developed and characterized, and it was demonstrated that their electrochemical performance was greatly improved by the effective removal of the thermoplastic support polylactic acid (PLA) as well as the formation of sponge-like and low-dimensional carbon nanostructures. This reagent-free approach consists of a direct, fast, and automatized spark discharge between the 3D-electrode and the respective graphite pencil electrode tip using a high-voltage power supply. Activated electrodes were challenged toward the simultaneous voltammetric determination of dopamine (DP) and serotonin (5-HT) in cell culture media. Spark discharge has been demonstrated as a promising approach for conductive filament activation as it is a fast, green (0.94 GREEnness Metric Approach), and automatized procedure that can be integrated into the 3D printing pipeline.