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Continuous silicon carbide (SiC) fibers, as reinforcement of ceramic matrix composites, have broad application prospects in the fields of aviation, aerospace and nuclear energy. Three typical KD-SiC fibers were adopted to explore the relationship of the composition and structure with their long-term oxidation (1–100 h) resistance in air environment. The mechanical strength retention of the nearly stoichiometric polycrystalline SiC fiber (C-1) was generally higher than that of the SiC fiber (C-3) with excess carbon and low oxygen, also higher than the nearly stoichiometric SiC fiber (C-2), especially under oxidation conditions of higher temperature and longer holding time. By comparing the high-temperature resistance with oxidation resistance at 1200–1600 °C, it was found that the oxidation reaction was the dominant factor affecting the mechanical properties. This work could provide theoretical and practical references for improvement of oxidation resistance of SiC fibers and their composites. [ABSTRACT FROM AUTHOR]

Porous silicon carbide ceramics are ideal candidates for filters, separation membranes, and high‐temperature structural materials, for which high porosity and precise pore size control are required. However, high porosity and large pore sizes usually lead to degradation in mechanical properties. In this work, silicon carbide powder with two different particle sizes was used as the raw material, and C powder and SiO2 powder were used as pore‐forming agents. A series of pure silicon carbide porous ceramics with micron‐sized pores were prepared by recrystallization sintering. The porosity and pore size of obtained samples were controllable and adjustable, and the mechanical properties were significantly enhanced. The microstructure, pore size distribution, porosity, and crystal phase of silicon carbide porous ceramics were characterized by scanning electron microscope, pore size analyzer, Archimedes method, and X‐ray diffraction. The effect of adding C/SiO2 on the porosity, the pore size, and the micro‐morphology of sintering samples was studied. The results show that C/SiO2 can adjust the porosity and pore size of pure silicon carbide porous ceramics in a wide range. The highest porosity of the obtained sample adding 40% C/SiO2 was up to 64.42%, and the average and maximum aperture are 5.42 and 11.98 µm, respectively. [ABSTRACT FROM AUTHOR]

Electron irradiation‐induced acceleration of self‐healing and high‐temperature oxidation has been discovered in SiC/Y2Si2O7–Y2SiO5 composites. Bulk samples were produced by pulsed electric current sintering. These samples were exposed to an electron beam from the pulsed intense relativistic electron beam accelerator with a beam energy of 2 MeV at irradiation doses of 10–40 kGy. The self‐healing and high‐temperature oxidation experiments were carried out at 1100–1300°C for 1–24 h in laboratory air. Electron irradiation significantly improved the self‐healing effectiveness. The closure of surface cracks was caused by the volume expansion of SiC via transformation to SiO2 and the outward diffusion of Y3+ ions. Electron irradiation also increased the thickness of the internally oxidized zone, formed by the inward diffusion of O2− ions. Enhanced self‐healing and oxidation behavior were associated with defect formation induced by electron beam exposure, which facilitated the diffusion of ions within the crystal lattice. [ABSTRACT FROM AUTHOR]

This study aims to investigate the effects of the surface roughness of an aluminium substrate on the adhesive joint strength of aluminium–aluminium specimens prepared using epoxy and methyl methacrylate adhesives for shear strength tests. Aluminium surfaces were mechanically abraded using silicon carbide (SiC) papers with different grit sizes in two different modes. The evaluated bonding performance characteristics included the maximum bonding strength and residual strength of the adhesive joints after their exposure to various environmental conditions. The results demonstrated that excellent adhesion characteristics were obtained at the optimum SiC grit size (grit-80) regardless of the adhesive type. In addition, the topographical and morphological properties of the aluminium surfaces were studied before and after mechanical abrasion via surface profilometry and scanning electron microscopy, respectively. A possible mechanism was proposed to explain the observed shear strength changes and respective modes of fracture after sample exposure to air, de-ionised water, and aqueous salt solutions. [ABSTRACT FROM AUTHOR]

Graph theory has many applications in chemistry and is used to analyze molecular structures. Topological descriptors are numerical numbers that contain chemical information and provide structural features of a compound associated with a chemical approach. The purpose of the topological index is to study the physicochemical properties of molecular structures. This paper investigates the molecular graph of 2D silicon carbide structures. The scope of this paper is to determine the highest thermal stability property among silicon carbide structures using topological indices. [ABSTRACT FROM AUTHOR]

In this study, molecular dynamics simulations were employed to investigate the effect of symmetrical tilt grain boundaries (STGBs) on the cascade collision evolution at the SiC/PyC interface. We observed that the tilt angle size of grain boundary (GB) spatial structures significantly influences both the type and number of defects caused by primary knock-on atom (PKA) collisions at the interface, altering the cascade damage morphology. Under the PKA range from 1.5 keV to 15 keV at 1000 K, the interplay between GB and interface damage throughout various cascade collision stages impacts defect generation and PKA efficiency. Integrating the analyses of displacement cascade morphology, threshold displacement energy (TDE), and Frenkel pairs (FPs) evolution, it is evident that GBs introduced into the SiC/PyC interface with single crystals exhibit reduced defect absorption efficiency. This implies the existence of competing mechanisms of GB damage and interfacial damage. Notably, the GB plane near the interface exhibits enhanced irradiation resistance and atomic arrangement stability compared to areas without GB. Overall, our results offer crucial insights into the irradiation resistance mechanics of ceramic composite interfaces, laying the groundwork for future studies. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) can form many different polytypes but their energetic ordering and frequency of occurrence are still not fully understood. In this study, polytype stability in pure and doped SiC as well as charged defects are studied by first‐principle calculations. The dopants under investigation include N and Al which are added as single dopants and also as dopant pairs. Regarding pure SiC, our findings align with previous works which have shown that energy differences between polytypes are smaller than uncertainties related to the choice of exchange‐correlation functional. In contrast, the effects of doping are predicted consistently for different xc functionals with N doping leading to a stabilization of the 3C polytype while Al doping causes only minor changes. This effect is explained based on the differences in the band‐gap of the polytypes and the dopant‐induced defect states in agreement with an explanation suggested by Heine et al (J Am Ceram Soc. 1991;74(10):263033). We further corroborate this explanation with calculations of charged dopants. As a consequence, Al in proximity to N can entirely neutralize the donor and its stabilization effect on 3C. Furthermore, a strong attraction (1.8–1.9 eVs) is observed between the two dopants which indicates that they will occur in pairs. Our results provide a more complete picture of SiC doping and we discuss its implications for the crystal growth process. [ABSTRACT FROM AUTHOR]

This study systematically explores the wetting characteristics of re‐entrant microstructures, focusing on the interplay between the unique geometries and material compositions. While silicon dioxide (SiO₂) re‐entrant microstructures are previously studied, this research pioneers the fabrication of silicon carbide (SiC) re‐entrant microstructures. Through experimental approaches and theoretical analysis, the research assesses how variations in geometry and material impact wettability. Key findings reveal that SiC re‐entrant structures achieve an average contact angle of 145°, closely matching the 148° observed for SiO₂, indicating similar hydrophobic behavior. Although flat SiC surfaces exhibit higher inherent hydrophobicity than flat SiO₂ (59° vs 26° contact angle), re‐entrant geometry predominantly influences wetting behavior, overshadowing material differences. Structures with lower solid area fractions show increased hydrophobicity, with a distinct hierarchy: microlines are the least hydrophobic, followed by shark‐skin textures, rectangles, circles, and triangles. Additionally, increasing the gap size between structures enhanced hydrophobicity up to a critical point. This study paves the way for optimizing re‐entrant microstructures for specific applications, significantly enhancing the understanding of surface science and advancing material design. [ABSTRACT FROM AUTHOR]

Combined with the fabrication of low-dimensional materials, certain silicon carbide color centers can become excellent platforms for nano-optics, and be applied to quantum and biomedical fields. In this work, color center nanoparticles were prepared based on high purity semi-insulating silicon carbide substrate using liquid-assisted femtosecond laser machining. Effects of multi-pulse array ablation and line scanning fabrication were investigated, and parameters such as repetition frequency and pulse number were also optimized. We employed photoluminescence spectroscopy, field emission scanning electron microscopy and transient fluorescence spectroscopy to characterize optical properties and micromorphology of nanoparticles. The broadband photoluminescence within the range of 850–950 nm should be attributed to silicon vacancy color centers, and V1/V1' zero-phonon lines were confirmed at low temperature. It is noted that the femtosecond laser annealing is critical for the luminescence enhancement of color center nanoparticles. The evolution of particles and cavitation bubbles during processing was elucidated. After optimization, silicon vacancy color center nanoparticles were prepared by multi-pulse (107) array ablation and 200 kHz pulse repetition frequency, with an average diameter of approximately 15 nm and an average density reaching 273.94 counts/μm2. The sample can be preserved stably in the form of nanoparticle solutions. Processing methods and corresponding conclusions of this study would be applicable to the femtosecond laser fabrication and micromorphology control of color center nanoparticles of various hard-brittle semiconductors. [ABSTRACT FROM AUTHOR]

Humidity sensors are essential for monitoring humidity levels in various fields. This paper investigates the development and optimization of humidity sensitive SiC-Fe 3 O 4 polymer nanocomposites with varying Fe 3 O 4 concentrations fabricated using Direct Writing (DW) process. The inks were evaluated for flow behavior to ensure proper extrudability through the nozzle. The rheological behavior was then correlated with the printing parameters to optimize the printing accuracy of the nanocomposites. It was observed that all the inks exhibited shear-thinning behavior, enabling a smooth extrusion process. To ensure high-resolution features, a new image analysis method was introduced to quantify corner rounding in printed features, enabling the optimization of printing parameters. In terms of humidity sensing performance, all the inks displayed a change in electrical properties with humidity adsorption. The fabricated nanocomposites showed a decrease in electrical conductivity with increasing humidity, suggesting potential for humidity-sensing applications. Notably, the humidity sensitivity of the nanocomposites was highly dependent on the Fe 3 O 4 concentration in the inks. These findings provide valuable insights into the DW of SiC-Fe 3 O 4 polymer nanocomposites for humidity sensing applications. [ABSTRACT FROM AUTHOR]

Residual strain in an epilayer grown on a foreign wafer induces epiwafer's bow, that is often considered undesirable. Wafer bow however, can be advantageous because both the direction and magnitude of strain are vital for the fabrication of various Micro Electro Mechanical Systems (MEMS), such as resonators. Here strain control is reported for highly mismatched heteroepitaxy of cubic silicon carbide (3C–SiC) compound semiconductor on silicon (Si), a prized functional material, dependent solely on carbon to silicon ratio (C/Si) during growth. While Si–rich condition enhances growth and generates positive curvature i.e. tensile strain, C–rich condition suppresses growth and produces negative curvature i.e. compressive strain. An optimum region emerges with virtually no strain and superior crystallinity. Our findings are significant for the knowledge of heteroepitaxy of 3C–SiC and may be broadened to heteroepitaxy of other compound semiconductors. [ABSTRACT FROM AUTHOR]

This study investigates the efficacy of an epoxy composite system that incorporates hybrid nanofillers consisting of multi-walled carbon nanotubes (MWCNTs), and silicon carbide nanoparticles (SiCs), as a means of reinforcing epoxy matrices with enhanced thermal properties. The fabrication of epoxy hybrid nanocomposites was carried out through a solution mixing process involving ultrasonication and planetary centrifugal mixing. Before proceed with the analysing synergistic effect of hybrid filler ratios, the samples were first being investigated on the effect of filler loadings to determine the optimal fillers loading, and it was discussed in other study. It was found that there was a correlation between the thermal properties of the specimens and their respective filler loadings, which an increase in filler loadings led to an increase in thermal properties. The incorporation of 4 vol.% of MWCNTs resulted in a significant enhancement of the thermal conductivity of the composites, reaching a value of 0.46 W/mK. This represents a doubling of the thermal conductivity compared to that of pure epoxy (~0.2 W/mK). Moreover, the hybrid fillers loadings of 3vol.% MWCNT+1vol.% SiC shows a higher thermal conductivity value of 0.48 W/mK which indicates the synergistic effects of hybrid fillers. The epoxy matrix exhibited uniform dispersion of MWCNTs and SiCs, resulting in the establishment of thermally conductive pathways. [ABSTRACT FROM AUTHOR]

This work presents experimental and numerical results of deposition of SiC coating using TIG torch method. The Taguchi approach was used to optimize the TIG torch melting process of duplex stainless steel for increasing the wear properties. The process variables used are current, voltage, transverse speed and gas flow rate. The parameter combinations were carefully chosen with the purpose of producing a hard surface layer with the enhancement of wear properties. Three levels of parameters were used in the experimental design in accordance with L9 orthogonal array. The signal-to-noise (SN) ratio was employed to analyze the experimental data. The results show that the current provides the most influencing parameter while the transverse speed provides the least contribution on the improvement of wear properties. The optimize parameter on the hardness and wear rate is 80 A of current, 20 V of voltage, 1.0 mm/sec of transverse speed and 25 L/min of argon flow rate. The main worn surface mechanism for SiC-DSS reinforced surface exhibited mild striation for the best sample of hardness and wear resistance. [ABSTRACT FROM AUTHOR]

This paper presents the results of obtaining bulk silicon carbide (SiC) ceramic samples using the SPS (Spark Plasma Sintering) method with carbon of various origins for the synthesis of the initial SiC powder. A correlation was established between the pore volume in the initial powder, carbon, and the resulting ceramics. Scanning electron microscopy (SEM) revealed differences in the surface morphology of the samples in terms of pore and channel size. The laser flash method was used to determine the heat capacity and thermal conductivity parameters of the obtained samples in the temperature range of 300–1100 K. It was found that as the temperature increases, the thermal conductivity of all samples decreases and ranges from 20 to 60 W/(m K). The produced ceramics can be used for manufacturing heat-resistant products. The raw materials that provide the best relative density parameters and, consequently, the properties of bulk silicon carbide samples were identified in the studied series. [ABSTRACT FROM AUTHOR]

Natural fibre indused hybrid polymer has emerged over the past decade along various sectors including automobile, structural and much more. The biodegradability of the hybrid composite makes it more versatile in the current global industry. The present work focuses on fabrication such hybrid composite from kenaf fibre, silicon carbide, and epoxy resin polymer. Adding the silicon carbide filler material enhances the electrical and thermal characteristic where as the kenaf fibre act as reinforcement for structural integrity. A set of six composite specimens were produced, with variations in the weight% of silicon carbide. After that, these samples were put through several thermal tests, such as "differential scanning calorimetric (DSC), thermo gravimetric analysis (TGA), coefficient of thermal expansion (CTE), thermal conductivity (TC), and heat deflection temperature (HDT)". This work has been intended to expand the range of possible applications for composites reinforced with silicon carbide or kenaf fibres by emphasizing their potential for enhanced thermal stability, improved performance, and reduced thermal expansion in comparison to traditionally used other filler materials with composite structures. [ABSTRACT FROM AUTHOR]

In this study, AMCs is made by incorporating fly ash (FA) and silicon carbide (SiC) particles into Al 7475 through the stir casting method. The fabrication of samples involves changing parameters such as stirring speed (ST), stirring time (SI), and the weight% of FA and SiC (RE). The pouring temperature is maintained at a constant 700 °C throughout the casting process. This investigation specifically employs an Artificial Neural Network (ANN) model to forecast the ultimate tensile strength (UTS) and Brinell Hardness (BHN) of the resulting composite. Utilizing a wide-ranging dataset, a well-suited model is established to validate mechanical properties, enabling predictions for unidentified data. The ANN architecture (3–10–2) is depicted with high correlation coefficients 0.99703 for training, 1 for validation and testing), and an overall coefficient of 0.99513. The network is evident in the comparison between predicted and experimental results, affirming the viability of ANN in modelling effective stir casting parameters. [ABSTRACT FROM AUTHOR]

Engineering ceramics and their composites are widely used owing to their excellent properties, including high wear, corrosion and heat resistance, low friction coefficient, and low thermal conductivity; thus, the current paper presents a comprehensive review of the most common types of engineering ceramics, demonstrating their key properties, advantages, potential applications, and challenges. This paper also provides prevailing methods for tackling the engineering ceramic challenges and maximizing their applicability. This review paper focuses on alumina (Al2O3), silicon carbide (SiC), zirconia (ZrO2), aluminum nitride (AlN), and silicon nitride (Si3N4), and explores their usability in automotive, aerospace, and tribological applications. Additionally, the incorporation of reinforcing nanomaterials, i.e., graphene and carbon nanotubes or their combination with second-phase reinforcing nanomaterials in these types of ceramics to improve their physico-mechanical properties is also discussed. By strategically adding these reinforcing materials, the brittleness of ceramics can be mitigated, leading to materials that are more suitable for demanding applications in various high-performance industries. [ABSTRACT FROM AUTHOR]

Cost-effective decarbonization and structural strengthening of carbon-containing refractory materials are crucial for the development of low-carbon steel (LCS) and ultra-low-carbon steel (ULCS) technologies. In this study, a carbonaceous-ceramic reinforcement assembly structure composed of multilayer graphenes and silicon carbide whiskers/particles (MLGs-SiC w /SiC p) has been successfully designed and fabricated. By employing three-roll milling (TRM) for low-cost exfoliation of expanded graphite (EG) into MLGs in a phenolic resin (PF) medium, we optimized the exfoliation cycles to fine-tune the morphology of MLGs. Subsequently, the catalytical solid-state conversion of PF/MLGs reacting with Si into SiC w /SiC p at 1400 °C, under varying C/Si molar ratios and catalyst contents, not only retained the structural integrity of MLGs but also embedded them within a novel SiC w /SiC p composite matrix. Our research elucidates the catalytic conversion mechanism, underscoring the significant role of nickel catalysts in promoting efficient SiC conversion. This work offers a promising pathway for developing high-performance, economical, low-carbon refractories. [ABSTRACT FROM AUTHOR]

This paper studies the temperature-dependent electrical transport properties of nickel (Ni) and nickel–chromium (Ni–Cr) sputtered on n-type 4 H-SiC substrate. Barrier inhomogeneities have been found to affect the electrical parameter of the Schottky barrier diode (SBD) from 323 to 423 K temperature range, We have done current–voltage characterization of Ni and Ni–Cr Schottky junctions. The barrier height (ϕ Bo) , reverse saturation current (I r) , ideality factor (η) and series resistance (R s) were obtained from I–V characteristics of Ni and Ni–Cr and these parameters are observed to be highly dependent on temperature. It has been observed that Ni–Cr contact has exhibited better electrical characteristics as well as thermal sensitivity as compared to Ni. This may be attributed to the smaller number of barrier inhomogeneities at the Ni–Cr/4 H-SiC interface. In the temperature range from 323 to 423 K, Ni and Ni–Cr-based Schottky contacts, Following observation has been noticed (a). Schottky barrier height (SBH) increased from 1.24 to 1.37 eV and 1.15 to 1.45 eV, (b). Ideality factors reduced from 3.76 to 2.61 and 3.20 to 2.53, (c). Series resistance decreased from 10.22 to 3.37 Ω and 2.45 to 1.16 Ω , and (d). Reverse leakage current 524.88 × 10 - 12 to 79.66 × 10 - 9 A and 557.32 × 10 - 12 to 1.51 × 10 - 9 A respectively. The V–T curves for both SBDs are investigated (for the same temperature range) to calculate their thermal sensitivity (α) at 1.0 × 10 - 4 and 5 × 10 - 10 A, respectively. The V–T curves with linear behavior are used to calculate the thermal sensitivity coefficient (α) , which was found to be 7.11 to 7.93 mV/K for the Ni–Cr SBD, and 7.1 to 20.01 mV/K for the Ni/4 H-SiC contacts. The sensitivity-current (α - I) characteristics for the Ni/4 H-SiC SBD were found to be a non-linear comparison with Ni–Cr/4 H-SiC SBD, which may be attributed to the presence of a highly resistive and non-uniform coating of Ni at the interface. [ABSTRACT FROM AUTHOR]

Transmission optical absorption spectra of ion-irradiated 3C-SiC epitaxial films on a silicon substrate are measured in the visible-near infrared range from room temperature down to about 10 K. These data show strong interference fringe patterns on top of the silicon absorption edge at about 10,460 cm1 which limits the transmittance of the samples. The radiation damage by 2.3-MeV Si+ and 3.0-MeV Kr+ ions is studied by following the impact of ion irradiation on these transmission spectra as a function of ion fluence and at various temperatures. The temperature dependence of the optical gap of silicon is deduced from the evolution of the fundamental absorption edge and that of the refractive index of SiC is deduced from the evolution of fringe spacing. The low temperature measurements evidence the shrinkage of band gap of silicon which is assigned to the gradual amorphization of the ion-implanted zone of the substrate as a function of fluence. These new results bridge a gap in the data on the properties of ion-induced damage in silicon carbide and silicon. [ABSTRACT FROM AUTHOR]

Silicon carbide particle reinforced aluminum matrix composites (SiCp/Al), combine the properties of aluminum matrix materials and reinforced silicon carbide (SiC) particles, finding widespread application in aerospace, optics, and electronics. The increased hardness and electrochemical inertness of SiC particles present significant challenges in their processing. This research investigates the impact of photocatalytic processes on machining accuracy in electrochemical processing (ECM). The dissolution characteristics of SiCp/Al during ECM and photocatalytic-assisted electrochemical machining (PAECM) were analyzed with varying electrolyte compositions, using polarization curves and oxidation–reduction potential (ORP). Validation of improved machining accuracy and surface quality in PAECM was achieved through no-feeding machining. According to theoretical principles and laboratory analyses of the workpiece surface, it was found that PAECM, through its photocatalytic reaction, generated more oxides, blocked stray currents and stray corrosion effectively, and attained accuracy in profile creation. Through a comparative analysis it revealed that PAECM exhibited smoother profiles and reduced Overcut Ratio (OCR) in hole and groove machining compared to ECM, particularly in groove machining. Adjusting machining gaps as well as reducing abrasive particle size in PAECM influenced groove depth and width, which achieved optimal morphology with a 0.4 mm gap and a 2–3 nm abrasive particle size, resulting in a 370 μm depth. [ABSTRACT FROM AUTHOR]

Aluminium metal matrix composites (AMMCs) using alumina (Al2O3) and silicon carbide (SiC) as reinforcement elements are gaining significant interest in various applications because of their excellent properties. In this study, Al2O3/SiC with compositions (0.5 wt.%, 1.5 wt.%, and 2.5 wt.% for each) were used as reinforcement elements in an aluminium alloy (AA2024-T6). The samples prepared were AA2024-T6 + (0.5Al2O3/0.5SiC), AA2024-T6 + (1.5Al2O3/1.5SiC), and AA2024-T6 + (2.5Al2O3/2.5SiC) using a stir-casting technique. The experimental study included density calculation mechanical properties, such as tensile strength, compressive strength and hardness. The study also included a microstructure examination of the fracture surface of the tensile specimens. The results showed that incorporating Al2O3/SiC as reinforcement materials into aluminium AA2024-T6 significantly improved its properties. Hence, increasing the reinforcement with compositions of 2.5Al2O3/2.5SiC into AA2024-T6 showed a drop in density and increased mechanical properties, such as ultimate tensile strength, compressive strength and hardness, compared to the base alloy (AA2024-T6). Furthermore, the scanning electron microscopy analysis revealed the uniform distribution of the reinforcement particles resulting in strong bonding with the matrix. The findings suggest that Al2O3/SiC reinforced with AA2024-T6 can be used in applications where a combination of lightweight and high strength is needed. [ABSTRACT FROM AUTHOR]

This study aims to develop a reference material that enables precise management of dopant distribution in power semiconductors. We thoroughly investigate the structural and surface properties of 4H-silicon carbide (4H-SiC) single crystals implanted without annealing using aluminum (Al) and phosphorus (P) ions. Ion-implanted 4H-SiC was thoroughly evaluated using advanced techniques, including X-ray diffraction (XRD), field emission transmission electron microscopy (FE-TEM), atomic force microscopy (AFM), time of flight medium energy ion scattering (ToF-MEIS), and secondary ion mass spectrometry (SIMS). The evaluated results indicate that, without post-annealing, ion-implanted 4H-SiC can serve as an effective reference material for the precise control of trace elements and the quantitative monitoring of dopant distribution in power semiconductor applications. [ABSTRACT FROM AUTHOR]

A structural study of the transformation of 6√3 reconstruction on the surface of a 4H–SiC substrate into quasi-free epitaxial graphene was carried out by the reflection high-energy electron diffraction (RHEED) method. The conversion was carried out via hydrogen intercalation between the reconstructed layer and the adjacent top layer of SiC. The initial 6√3 reconstruction was obtained during short sublimation annealing of the 4H–SiC substrate in an argon medium. A slight violation of the 6√3 reconstruction layer formation uniformity was found. The results of the study of the crystal structure of quasi-free-standing graphene and single-layer graphene comprising a buffer layer formed on 4H–SiC in the traditional way in an Ar atmosphere without intercalation were compared. [ABSTRACT FROM AUTHOR]

The present work examines the tribological characteristics of cast aluminium–silicon matrix composites reinforced with silicon carbide (SiC) and graphite (Gr). The metal matrix composite samples were manufactured using stir and squeeze casting techniques, employing an Al–Si matrix alloy and integrating particulate SiC and varying quantities of graphite particles. To investigate the impact of varying amounts of graphite on the Al/SiC composite, graphite particles were included at volumetric proportions of 5, 7.5 and 10%. Before being integrated into the matrix, Cu-coating was employed on graphite particles using electroless coating to enhance the adhesion with the matrix composition. Tribological experiments were conducted on Al/SiC and the Al/SiC/Gr composites using a pin-on-disc tribometer apparatus. Al–SiC and Al/SiC/Gr samples were specifically engineered and employed as a pin, while AISI 8620 steel was utilized as a disc. Adding graphite particles to the Al/SiC composite decreased the amount of wear and friction. The utilization of hybrid Al/SiC/Gr composites resulted in the creation of tribo-layers during sliding, hence minimizing the occurrence of grooves, plowing and smearing. [ABSTRACT FROM AUTHOR]

The document discusses the importance of developing new materials to meet the increasing energy needs of society. It focuses on carbon-related composites for sensors and energy storage, presenting state-of-the-art research on their synthesis, properties, and applications. The Special Issue includes 19 original research articles and review papers that cover a wide range of topics, from the use of carbon fibers in various applications to the development of supercapacitors and batteries using carbon-based materials. The articles aim to provide new insights into the field of carbon-related materials for sensing and energy storage applications. [Extracted from the article]

The dissolution rate of SiC in molten Fe–C alloys was investigated at 1673 ~ 1773 K, while the initial carbon concentration varied from approximately 2–3 wt%. The dissolution of SiC in molten Fe–C alloys occurred to reach the carbon-saturation composition. By assuming a first-order reaction, the dissolution rate constant was estimated to decrease from 8.17 × 10−3 to 2.90 × 10−3 cm/s, as the initial carbon content increased from 2 to 3 wt% at 1673 K. When the temperature increased from 1673 to 1773 K with the sample of the initial carbon content of about 2 wt%, the rate constant increased from 8.17 × 10−3 to 18.41 × 10−3 cm/s. The apparent activation energy was estimated at 199.5 kJ/mol. Based on the experimental results, an empirical equation was suggested for the estimation of the SiC dissolution rate constant: ln k c m / s = 12.74 - 1.37 × w t % C t = 0 - 2.40 × 10 4 / T K , which can be applied to the numerical simulation of the Si-pickup in the FINEX and the Hydrogen-enriched Blast Furnace operations. [ABSTRACT FROM AUTHOR]

Objective: The study aimed to optimize protocols for the joint extraction of deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) from 0.025 × 106 CFU of Candida albicans, targeting to overcome the challenges in the extraction of these genetic materials. Materials and methods: From this, treated silicon carbide (SiC) granules were added to fungal samples from methods 1, 2, and 3 obtained from aliquots of BHI or Sabouraud medium to cause cell lysis and enable the isolation of these macromolecules by phenol and chloroform. The concentration and integrity of the extracted nucleic acids were analyzed, respectively, by spectrophotometry using the A260/A280 ratios and 1% agarose gel electrophoresis. Results: Therefore, method 3 is the one that most comprises samples considered pure of both DNA and RNA, simultaneously. Furthermore, the presence of intact RNAs corresponding to the base pair size such as 5.8 S rRNA and tRNA was verified during electrophoresis, considering the particularities of RNA, which makes it very unstable and easily degraded. Conclusions: Thus, it results in a faster and simpler method in addition to obtain promising results using minimal amounts of biological sample and offering a valuable alternative for small laboratories to work with molecular biology. [ABSTRACT FROM AUTHOR]

This work presents a comprehensive study on the dielectric properties of shellac-based composites with varying filler concentrations of (SiC) and iron (Fe) particles, complemented by scanning electron microscopy (SEM) analysis. Shellac, a natural biopolymer known for its excellent film-forming abilities, biodegradability, and insulating properties, was chosen as the matrix material. The dielectric properties, including permittivity and dielectric loss, are measured by LCR Meter across a frequency range from 100 Hz to 8 MHz to evaluate the effects of filler concentration. This study reveals that the incorporation of SiC and Fe particles significantly enhances the dielectric constant and exhibits complex frequency-dependent behavior in dielectric loss. SEM analysis provided insights into the microstructural changes induced by the fillers, correlating with the observed dielectric properties. The results indicate that the dielectric performance of shellac composites can be effectively tailored through the precise control of SiC and Fe particle concentrations, attributed to interfacial polarization and Maxwell-Wagner-sillars effects. This work underscores the potential of shellac composites as sustainable, high performance dielectric materials for advanced electronic applications, contributing to the development of eco-friendly electronic devices. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) stands out for its remarkable hardness, thermal stability, and chemical resistance, making it a critical material in advanced engineering applications, particularly in power electronics, aerospace, and semiconductor industries. However, its inherent brittleness and relatively low fracture toughness pose significant challenges during precision manufacturing processes, particularly during the laser stealth dicing—a pivotal process for wafer separation. This review provides a comprehensive analysis of the fracture toughness of SiC, exploring its dependence on microstructural factors, such as grain size, fracture mode (transgranular vs. intergranular), and toughening mechanisms, including the crack deflection and bridging. The effects of temperature and mechanical anisotropy on the fracture resistance of SiC are discussed. Particular attention is given to how SiC's low fracture toughness and brittle nature affect the controlled crack propagation critical to the dicing process. The review synthesizes key experimental findings from various fracture-toughness measurement techniques, highlighting their relevance for optimizing the laser processing parameters. By linking the fracture mechanics of SiC to its performance in laser stealth dicing, this review provides critical guidance for enhancing the process, ensuring greater efficiency and reliability in SiC wafer separation for advanced technologies. [ABSTRACT FROM AUTHOR]

The NiCrMoSiC composite cladding on Titan-31 base alloy was produced using a hybrid microwave heating process. The produced claddings were examined for microstructural, phase analysis, microhardness, and surface roughness using suitable techniques. The linear reciprocator ball on plate wear test was conducted using a static alumina indenter on microwave cladding. Studies have been done on track specifications for friction and wear. It is feasible to fabricate a dense microstructure with uniform distribution of hard phases, absence of pores and fractures, and strong metallurgical bonds. Typically, cladding is two times as durable as the underlying metal. The cladding has a lower coefficient of friction than the substrate as a result of enhanced hardness and improved internal lubricity brought on by the production of hard carbide phases. [ABSTRACT FROM AUTHOR]

In this article it is established that the physical and mechanical characteristics of reaction-sintered silicon carbide ceramics are directly sensitive not only to the parameters of structure fault detection, but also to the totality of the homogeneity of the distribution of all components in the volume of the material, which largely determines the technological parameters of the molding ceramic powders. [ABSTRACT FROM AUTHOR]

A novel planar silicon carbide (SiC) MOSFET integrated with both MOS-channel diode (MCD) and junction barrier Schottky diode (JBS) on the same chip (MCD-JBSFET) is proposed and investigated through Technology Computer-Aided Design (TCAD) simulations in this paper. The proposed device features the lowest turn-on voltage and the best current conduction capability under the reverse-biased conditions, allowing it to achieve the same reverse conduction capability with fewer MCDs compared to conventional MOSFET with MCD structures (MCDFET). This reduction in the number of MCDs enables more channels to operate under forward-biased conditions, thereby improving power density. Compared to a conventional MOSFET integrated with JBS structure (JBSFET), the reverse current in the MCD-JBSFET flows through both the MCD and JBS, which suppresses the peak lattice temperature at Schottky contact and enhances the high-temperature robustness, especially under surge current conditions. In addition, the split-gate structure in the proposed structure optimizes the reverse capacitance and the figure of merit Ron,sp × Qg by factors of 0.65 and 2.15, respectively. Finally, the switching losses are reduced by 40.2%, indicating the suitability of MCD-JBSFET for high-frequency and high-current applications. [ABSTRACT FROM AUTHOR]

The evaporation dynamics of sessile droplets on re-entrant microstructures are critical for applications in microfluidics, thermal management, and self-cleaning surfaces. Re-entrant structures, such as mushroom-like shapes with overhanging features, trap air beneath droplets to enhance non-wettability. The present study examines the evaporation of a water droplet on silicon carbide (SiC) and silicon dioxide (SiO2) re-entrant structures, focusing on the effects of material composition and solid area fraction on volume reduction, contact angle, and evaporation modes. Using surface free energy (SFE) as an indicator of wettability, we find that the low SFE of SiC promotes quick depinning and contact line retraction, resulting in shorter CCL phases across different structures. For instance, the CCL phase accounts for 55–59% of the evaporation time on SiC surfaces, while on SiO2 it extends to 51–68%, reflecting a 7–23% increase in duration due to stronger pinning effects. Additionally, narrower pillar gaps, which increase the solid area fraction, further stabilize droplets by extending both CCL and constant contact angle (CCA) phases, while wider gaps enable faster depinning and evaporation. These findings illustrate how hydrophobicity (via SFE) and structural geometry (via solid area fraction) influence microscale interactions, offering insights for designing surfaces with optimized liquid management properties. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) has excellent mechanical and chemical properties and is used in a wide range of applications. It has the characteristic of rapidly heating up to several hundred degrees within one minute when irradiated with microwave radiation at 2.45 GHz. In this study, we investigated the oxidation curing process and microwave heating properties of polycarbosilane (PCS). A PCS disk-shaped green body was fabricated via uniaxial pressure molding. Silicon carbide was prepared by varying the pyrolysis temperature, and the heating characteristics of the microwaves were evaluated. The results showed that the samples pyrolyzed at 1300 °C after oxidation curing for 2 h at 180 °C rapidly heated up to 802 °C within 1 min, and the temperature remained constant for 120 min. The maximum temperature of the samples pyrolyzed at 1500 °C was relatively low, but the rate of heating was the highest. The microstructures and crystal structures of the microwaves as a function of the pyrolysis temperature were investigated. [ABSTRACT FROM AUTHOR]

Ranging from the most demanding technical applications to soft, extremely ductile wrapping foil, aluminum is one of the most versatile and reasonably priced metallic materials. These are attributable to the unique blend of features that it provides, together with its alloys, owing to its lightweight, and some of its alloys have higher strengths than that of structural steel. However, it is expected that the demand for aluminum will quadruple within the next 10 years, and as a result, the aerospace industry is increasingly turning to recycled alloys to fulfill its high demand. This study uses the ab initio method, implemented in the quantum espresso code, to examine the influence of pressure on the structural and mechanical properties of cubic silicon carbide alloyed with aluminum (Al) and magnesium (Mg). The study is motivated by the aerospace industry's growing need for sustainable materials. Some of the carbon atoms were swapped out for Al or Mg or both (co-doping) atoms in order to create the alloys. The results demonstrated that the application of pressure significantly influences both the structural and mechanical properties of the alloys, making them a promising option for the construction of environmentally friendly aircraft components. [ABSTRACT FROM AUTHOR]

In this report, the advanced manufacturing advantages of using supersaturated chlorinated chemistry are demonstrated at 1550 °C in 4H‐silicon carbide (4H‐SiC) epitaxy on trenches with different geometric profiles. Sloped mesa sidewalls (8°) show improved filling behavior compared with vertical sidewalls (2°) and lower the optimum chlorine/silicon ratio (Si:Cl) required to complete filling. Both the optimum Cl:Si ratio (10) and sidewall angle are lower for wider trench openings, allowing complete fill of 3 µm wide trenches (8 µm pitch, 5 µm depth) at a filling rate of 19 µm h−1. Excessive hydrogen chloride (HCl) diminishes filling by reducing sidewall growth and can also produce an end surface with very rough topography. This work demonstrates the importance of trench geometry on both the filling behavior and process optimization in chlorinated trench filling epitaxy for the manufacture of 4H‐SiC superjunction power electronics. [ABSTRACT FROM AUTHOR]

For the preparation of SiC nanowires (SiC NWs) by carbothermal reduction, it is of great significance to study the formation mechanism of sic nanowires for process optimization and the controllable preparation. Although first-principles molecular dynamics (FPMD) can simulate systems of hundreds of atoms on a picosecond time scale, the results of FPMD are still insufficient to elucidate the formation mechanism of core-shell SiC nanowires. To make up this deficiency, this article has conducted Deep Potential Molecular Dynamics (DPMD) simulation on nanoseconds timescales with near FPMD accuracy for systems containing thousands of atoms, the results more concretively show the formation process of core-shell SiC nanowires. DPMD simulation results show when CO molecules react with SiO molecules, CO molecules are wrapped by SiO molecules to form agglomerates, SiO molecules in the agglomerates that can come into contact with the wrapped CO molecules will react with wrapped CO molecules to form the SiC core, and SiO molecules that in the outer layer of the agglomerates will disproportionate into the amorphous SiO 2 shell. Furthermore, the formation mechanism of SiC nanowires was validated in combination with thermodynamics and experimental methods. Thermodynamic results show that vacuum conditions are favorable for the formation of SiO and CO and lower the temperature of SiC preparation. Finally, the core-shell structure of SiC NWs with good luminescence properties were successfully prepared by carbothermal reduction method using carbon black and silicon dioxide as raw materials under the pressure of less than 5 kPa. [ABSTRACT FROM AUTHOR]

This study investigates the effects of applied tensile and compressive stresses on the evolution of defects in He-irradiated silicon carbide (SiC) materials. By combining experimental studies with density-functional theory (DFT) simulations, we systematically analyzed the microstructural changes and defect formation mechanisms in SiC under stress. The research focused on He irradiation of SiC at 750 °C, with a fluence of 1 × 101⁷ He/cm2. The results revealed that the strain resulting from radiation damage depends on the applied stress during irradiation. Moreover, the formation of platelets is influenced by this applied stress: tensile stress promotes platelet growth, while compressive stress inhibits it. DFT simulations further supported these experimental findings by showing that under tensile strain, both carbon vacancies (Cv) and He atoms exhibit low energy barriers for migration. This phenomenon facilitates platelet growth, aligning well with the observations made in the experiments. However, when considering applications like semiconductor thin film transfer, such as the Smart-cut technique, He implantation under tensile stress can actually be advantageous. This approach enables the use of lower He fluence, which in turn reduces the overall cost of the operation. By strategically leveraging the effects of tensile stress on He implantation, it becomes possible to optimize processes like Smart-cut for more efficient and cost-effective thin film transfer in semiconductor manufacturing. [ABSTRACT FROM AUTHOR]

As a representative of third-generation semiconductors, silicon carbide serves as a new platform for quantum nano-optics with readable paramagnetic color centers such as silicon vacancies. The potential applications include biomedical imaging, quantum sensing and micro/nano environment detection. Color centers are usually prepared based on ion-irradiated substrates, then annealed at high temperature to increase the yield. Currently, annealing furnaces have been the main method to heat the substrate and achieve annealing of the whole sample. However, further exploration is still necessary for fine processing requirements such as specialized annealing regions with certain shapes. In this work, we applied femtosecond laser to achieve controllable annealing at micron scale, based on silicon carbide substrate after ion injection. The whole process of point, line and pattern annealing was realized. The annealing area demonstrates enhanced photoluminescence, attributed to silicon vacancy color centers. Raman and photoluminescence spectra reveal that the annealing effect is primarily influenced by the number of pulses per unit area. The mechanism of femtosecond laser annealing was introduced. Finally, the controllable annealing areas with various shapes were prepared based on the comprehensive optimal parameters (100 kHz pulse repetition frequency, 105 point annealing pulses, 10 μm/s line scanning speed). This annealing strategy demonstrates excellent stability and uniformity, as well as micron scale accuracy. Additionally, the excited state lifetime of silicon vacancy was extracted and quantified. The result means that femtosecond laser annealing enhances the optical properties and quantum application potential of color centers. This work can be further extended to other semiconductors as well as patterned modification of local surface/planes at some depth, and helpful to explore the mechanism and applications of femtosecond laser annealing. [ABSTRACT FROM AUTHOR]

Abrasive jet machining (AJM) process is commonly used for cutting and drilling of brittle materials in which the phenomenon of material removal can be considered as mechanical erosion by the impingement of high-velocity abrasives. The focus of this research is to compare the performance and economic benefits of recently developed hot abrasive jet machining (hot-AJM) with traditional AJM techniques when machining zirconia ceramic using silicon carbide (SiC) grain particles. The modified AJM employed abrasive air jet (combination of hot abrasive and compressed air) to strike on the work surface for material erosion. Briefly, the cutting performance is investigated by comparing the technological characteristics like material removal rate, machining cost, and taper angle of the developed hole. Abrasive grain size, nozzle pressure, and stand-off distance are considered as the variable factors for machining trials in accordance with the design of experiments. The usage of hot abrasives in AJM improved the material erosion owing to the occurrence of plastic deformation followed by deep chipping on the machined surfaces. From the results, it was observed that the hot-AJM outperformed the normal AJM with regard to improved material removal, reduced dimensional deviation of hole and minimal machining cost. According to the findings of the cost assessment, the machining of zirconia ceramic using hot-AJM was more cost-effective than using normal AJM since it resulted 25% reduction in the total cost of production. The overall machining cost expenditure per unit in hot-AJM was lower (INR 123.12) than expenditure in traditional AJM (INR 153.47). Machining with hot-modified AJM, compared to normal AJM, offers a more techno-economically viable solution for enhancing machinability. [ABSTRACT FROM AUTHOR]

Color centers in silicon carbide (SiC) offer exciting possibilities for quantum information processing. However, the challenge of ionization during optical manipulation leads to charge variations, hampering the efficacy of spin-photon interfaces. Recent research predicted that modified divacancy color centers can stabilize their charge states, resisting photoionization. This study presents a method for precisely creating single divacancy arrays in 4H-SiC using a focused helium ion beam. Photoluminescence tests reveal consistent emission with minimal linewidth fluctuations (∼50 MHz over 3 h). By measuring the ionization rate for different polytypes of divacancies, we found that the modified divacancies are more robust against resonant excitation. Furthermore, angle-resolved photoluminescence excitation spectra unveil two resonant-transition lines with orthogonal polarizations. Enhanced optical and spin characteristics were notably observed in these color centers compared to those generated through carbon-ion and shallow implantation methods, positioning modified divacancies as promising contenders for advancing quantum networking. Divacancy color centers in SiC are promising candidates for a spin-photon interface, but typically show charge-state instability under optical excitation. Here the authors show that modified divacancies created by a focused helium ion beam are robust against photoionization and have promising properties. [ABSTRACT FROM AUTHOR]

In this study, in-situ growth of columnar mullite reinforced silicon carbide porous membrane supports were prepared, and the addition of TiO 2 helped to reduce the sintering temperature for the anisotropic growth of necked columnar mullite crystals. The synthesis of in situ columnar mullite makes reasonable use of the oxidized silica of silicon carbide, and in turn reduces the loss of the silicon carbide porous membrane support under strong corrosive conditions. The material showed a flexural strength of up to 72.95 MPa, and a water flux of 31612.83 L·m−2·h−1·bar−1 when sintered for 2 h in an air environment at 1250 °C. The flexural strength after corrosion in 20 vol% H 2 SO 4 and 1 wt% NaOH solution (90 °C) exceeded 93 %. This shows that this porous silicon carbide ceramic membrane scaffold has potential applications in the field of water treatment under harsh environments. [ABSTRACT FROM AUTHOR]

As the most prospective media material for porous media burners, silicon carbide reticulated porous ceramic (SiC RPC) is required to possess a high porosity to fulfill efficient combustion, as well as exceptional thermal shock resistance to withstand the thermal stress generated during the start-up and shutdown processes. To achieve the strengthening and toughening of highly porous SiC RPC, three-layered struts were constructed, and in-situ whiskers were formed in SiC RPC through vacuum infiltration and sintering under a nitrogen atmosphere in this work. The results indicated that the three-layered struts were formed after the preform was conducted with vacuum infiltration, encompassing a mullite coating, a silicon carbide layer and a mullite inner layer. When Si powder and flake graphite were incorporated into the SiC slurry, numerous SiC whiskers were formed in situ within the SiC skeleton. The formation of SiC whiskers was attributed to the enhancement of SiC RPC, resulting in an increase in CCS from 0.22 MPa to 0.55 MPa. Additionally, the residual strength retention rate after water quenching at 1100 °C was elevated from 41.6 % to 70.2 %. Moreover, the SiC RPC containing SiC whiskers exhibited an impressively high porosity of 83 %, leading to a surface temperature of 688 °C and a heating efficiency of 16.4 °C/min during the combustion process. [ABSTRACT FROM AUTHOR]

We report temperature-induced complete de-wetting of phospholipid membranes from thermally evaporated silicon carbide (SiC) substrates, which occurs in the form of fractal patterns. Excess membrane material released as a result of de-wetting, transforms into fluid-filled membrane pockets, or leads to vesicle formation. The membrane pockets are composed of a double lipid membrane. These double bilayer superstructures, i.e. isolated membrane-enclosed fluid volumes, bring the internal contents into direct contact with the surface. This membrane morphology can be viewed as an alternative prebiotic assembly mechanism with possible implications for protocell development, where physicochemical surface interactions with internal primitive cell contents are greatly facilitated. [ABSTRACT FROM AUTHOR]

At present, wire sawing technology is the primary slicing method used for certain brittle materials, including monocrystalline silicon, sapphire, and silicon carbide. The surface quality of the sawn wafers significantly impacts subsequent machining processes, such as grinding and polishing. A theoretical model was developed to predict the amount of material removed per unit length of wire during the slicing of circular workpieces by a wire saw with reciprocating and rocking functions. Experiments were conducted during this study in which crystal ingots were sliced using a multi-wire saw, and the amount of material removed per unit length of wire was determined at different cutting positions on the workpiece cross-section. The surface roughness of each crystal wafer was measured systematically. The experimental results revealed that the surface roughness values measured at different points at the same y-coordinate position on a single wafer were approximately equal. However, the surface roughness was greatest on both the initial and final cutting edges and gradually decreased toward the wafer center. The surface roughness was also greatest for the wafer cut nearest to the new wire side, though it gradually decreased for wafers cut nearer to the center of the workpiece and remained relatively consistent from the middle wafer to the wafer cut nearest to the used wire side. The results also indicated that both the material removed per unit length of wire and the surface roughness of the wafer decreased with increases in the wire speed. The relationship between the material removed per unit length of wire and the surface roughness was approximately linear. When the material removed per unit length of wire was set to 0.00333 mm3/m, the average wafer surface roughness was 0.45 μm. [ABSTRACT FROM AUTHOR]

Aerospace and marine industries are constantly in search of materials that can provide good strength and durability while also being lightweight. Aluminium composites with adequate reinforcements have been proven to be effective in achieving incredible mechanical properties while also maintaining a good strength to weight ratio. Numerous studies have been done to study the various possibilities of matrix reinforcement combinations in aluminium composites. This work focuses on studying the effect of varying Cerium Oxide (CeO2) percentage in the aluminium composite on its tensile strength, hardness and corrosion resistance. CeO2 is used along with Silicon Carbide (SiC) and Multi-Walled Carbon Nanotubes (MWCNT) to develop four samples of hybrid aluminium composites with SiC and MWCNT constituting 1% and 0.1% of the composite and the weight percentage of CeO2 is varied between 1 and 2.5%. All the samples were fabricated using the modified stir casting process. The results show that the hardness and tensile strength of the composites peak when the CeO2% is at 2% while corrosion resistance only gets better with increasing reinforcement content. A significant enhancement in mechanical and physical properties of aluminium composite suggests that MWCNT is an effective hybridizing agent with SiC and CeO2 to develop aluminium composites. [ABSTRACT FROM AUTHOR]

SiC particle reinforced aluminum matrix composites (SiCp/Al) are widely used in aviation, weaponry, and automobiles because of their excellent service performance. Wire electrical discharge machining (WEDM) regardless of workpiece hardness has become an alternative method for processing SiCp/Al composites. In this paper, the temperature distribution and the discharge crater size of the SiCp/Al composite are simulated by a thermophysical model during a single-pulse discharge process (SPDP) based on the random distribution of SiC particles. The material removal mechanism of the SiCp/Al composite during the multi-pulse discharge process (MPDP) is revealed, and the surface roughness (Ra) of the SiCp/Al composite is predicted during the MPDP. The thermophysical model simulation results during the MPDP and experimental characterization data indicate that the removal mechanism of SiCp/Al composite material consists of the melting and vaporization of the aluminum matrix, as well as the heat decomposition and shedding of silicon carbide particles. Pulse-on time (Ton), pulse-off time (Toff), and servo voltage (SV) have a great influence on surface roughness. The Ra increases with an increase in Ton and SV, but decreases slightly with an increase in Toff. Moreover, compared with experimental data, the relative error of Ra calculated from the thermophysical model is 0.47–7.54%. This means that the developed thermophysical model has a good application and promotion value for the WEDM of metal matrix composite material. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) power modules are increasingly being used in high-voltage and high-frequency applications due to their superior electrical and thermal qualities. However, the issue of the partial discharge (PD) phenomenon raises serious reliability difficulties resulting in insulation failure, performance degradation, and potential device collapse. This paper provides a thorough assessment of the current PD detection strategies in SiC power modules. The issues provided by SiC devices' distinct operational features, such as high switching frequencies and higher voltage stresses, which hinder PD detection and mitigation, are widely investigated. This review compares the effectiveness, benefits, and limitations of various detection methods, emphasizing the need for better strategies to ensure long-term reliability and performance. This study gives an in-depth overview of the numerous forms of PD phenomena that occur in power modules, including internal and surface discharges, as well as how they appear under various detection systems. It examines the performance of several methods for power module technologies such as SiC. To address these PD issues, this article proposes ways to improve reliability and detection accuracy. [ABSTRACT FROM AUTHOR]

Silicon carbide (SiC) metal-oxide semiconductor field-effect transistors (MOSFETs), as a new material, have the advantages of low drain-source resistance, high thermal conductivity, low leakage current, and high switching frequency compared with silicon (Si)-based MOSFETs. Therefore, in many industrial applications, Si MOSFETs have been replaced by SiC MOSFETs. However, as the switching speed increases exponentially, some problems are amplified, the most serious of which is the overshoot of current and voltage. The increase in voltage and current slope caused by high switching speeds inevitably leads to overshoot, oscillations, and additional losses in the circuit. This paper focusses on the actual performance of the optimised switching strategy (OSS) in circuit testing and combines the existing simulation results to verify the practicability of OSS. In this paper, the optimised switching strategy is introduced first, and then, the LTspice model of SiC MOSFET is established in detail and verifies the feasibility of the OSS through half-bridge circuit simulation. Finally, the test platform is built using a programmable gate drive module (2ASC-12A1HP). Through a 400 V/30 A double-pulse test, the practicality of the OSS is verified. The experiments show that the OSS can greatly improve the switching performance of SiC MOSFETs. [ABSTRACT FROM AUTHOR]