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Hydrocarbon contamination is associated with light transmission losses in modern lithography machines, which contain extreme-ultraviolet-induced plasma. A volume-averaged global and deposition/etch surface model of a reference hydrogen/methane inductive discharge is developed to investigate the plasma–surface interactions. The simulation results are validated against a wide variety of experiments and verified with respect to multiple sets of computational data. The deposition rate is calculated for a variation in methane impurity (10–10 000 ppm), power, pressure, and net mass flow. The simulations conclude that the hydrocarbon plasma deposition can be minimized by reducing methane impurity and excluding solid organic structures. [ABSTRACT FROM AUTHOR]

In this study, we developed a hybrid machine learning technique by combining appropriate classification and regression models to address challenges in producing high-mobility amorphous In2O3:Sn (a-ITO) films, which were fabricated by radio-frequency magnetron sputtering with a nitrogen-mediated amorphization method. To overcome this challenge, this hybrid model that was consisted of a support vector machine as a classification model and a gradient boosting regression tree as a regression model predicted the boundary conditions of crystallinity and experimental conditions with high mobility for a-ITO films. Based on this model, we were able to identify the boundary conditions between amorphous and crystalline crystallinity and thin film deposition conditions that resulted in a-ITO films with 27% higher mobility near the boundary than previous research results. Thus, this prediction model identified key parameters and optimal sputtering conditions necessary for producing high-mobility a-ITO films. The identification of such boundary conditions through machine learning is crucial in the exploration of thin film properties and enables the development of high-throughput experimental designs. [ABSTRACT FROM AUTHOR]

1,2,3,4,5,6,7,8‐Octamethylcyclotetrasilazane (OTMSD), a cyclic silazane precursor, is deposited via atmospheric pressure plasma onto a substrate. The resulting coating exhibits a dual surface roughness, contributing to a significant reduction of surface wettability. Notably, the coating exhibits superhydrophobic characteristics, proven by a water contact angle of approximately 170°, hysteresis angle below 10°, very low tilting angle (<10°), and droplet‐bouncing effect. Importantly, this superhydrophobicity is achieved using OTMSD as fluorine‐free precursor with low reactivity to water. Furthermore, the deposition process is carried out using a commercially available plasma device highlighting its practicality and scalability for large‐scale production. [ABSTRACT FROM AUTHOR]

Due to its elemental abundance, nontoxic nature, and suitable optical-electrical properties, copper oxide is a valuable p-type semiconductor for photovoltaic (PV) applications. However, synthesizing copper oxide films for PV devices with a band gap close to the Shockley–Queisser limit (1.4 eV) using a one-step deposition process is important for maximum efficiency and synthesis simplification. In this work, cathodic cage plasma deposition (CCPD) of copper oxide (CuO + Cu2O) films on glass was performed to evaluate the microstructural, morphological, chemical, and band gap changes as a function of treatment time (2 h, 3 h, 4 h, and 5 h). The samples were analyzed by scanning electron microscopy, energy-dispersive spectroscopy, x-ray diffraction, and Raman spectroscopy to identify the morphology, chemical composition, and crystalline phases of the deposited films, and diffuse reflectance spectroscopy was used to calculate the band gap width. The films showed characteristics of absorbing material in the visible region with band gap values from 1.43 eV to 1.5 eV. However, the sample treated for 3 h had a compact coating with a thickness of 1.46 µm and band gap energy of 1.43 eV, showing the applicability of the CCPD technique for synthesizing copper oxide absorber layers with an optimum band gap in a single deposition step. [ABSTRACT FROM AUTHOR]

The preparation of resistant ultrathin film (utf) hydrogels coated onto different working surfaces (e.g., fabrics) is paying increasing attention as an advantageous strategy for customizing their resultant properties. More specifically, poly(ethylene glycol) (PEG)‐based utf‐hydrogels are relevant for their superior biocompatibility or antibiofouling properties. However, promoting the generation of poly(ethylene glycol) dimethacrylate (PEGDMA) cross‐links ideally without the use of initiators or other cross‐link agents, which might compromise the final bioactivity of the system, is complicated. Moreover, the actual synthesis techniques used for the preparation of such utf‐hydrogels face important drawbacks like high scale‐up costs or important geometrical restrictions, completely hindering its technological transfer. Herein, for the first time and easy and technologically scalable technology is reported for the synthesis and direct deposition of PEGDMA400 utf‐hydrogels onto different substrates based on atmospheric pressure nanosecond pulsed plasma approach. The advantages of the technology are explored and discussed, reporting the ready‐to‐use transparent coating of fabrics. After washing the samples using washing programs of a commercial laundry machine, coatings are still well adhered, showing excellent stability. Finally, the resultant properties of PEGDMA400 utf‐hydrogels are exhaustively characterized using in operando conditions in order to elucidate their potential capabilities in the biomedical field. [ABSTRACT FROM AUTHOR]

The development of cost-effective and high-performance bifunctional catalysts for overall water splitting is crucial for achieving sustainable clean energy. In this study, a metal/carbide hybrid (NiFeMo/NiFeMoCx) was prepared through fast and facile cathodic plasma electrolytic deposition. Due to the synergistic effect between the metal and carbide, NiFeMo/NiFeMoCx exhibited high activity in both the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER), with overpotentials of 230 mV and 60 mV at 10 mA cm−2, respectively. In addition, robust stability was demonstrated during the overall water splitting (1.52 V at 10 mA cm−2, with little degradation after 18 h of catalysis). This work provides a useful strategy for designing advanced water splitting catalysts for real application. [ABSTRACT FROM AUTHOR]

The preparation and realization of highly reliable thermal barrier coatings (TBCs) on the internal surface of complex cavities is a bottleneck problem. Traditional coating methods are difficult to deposit and fulfil service requirements. In this study, a novel structure of YSZ and Ce-doped YSZ (CeYSZ) TBCs was prepared by a newly cathode plasma electrolytic deposition (CPED) technology. The results suggested that both the CPED-YSZ and CPED-CeYSZ coatings exhibited porous cross-linked dendritic structures. Because Ce doping significantly improved the phase stability of tetragonal structure and enhanced thermal insulation temperature during a burner-rig test at 1300 °C, resulting in a threefold increase in the thermal cycling life of the CPED-CeYSZ coating compared to the CPED-YSZ coating. This work provided a new strategy for tailoring multiple rare-earth principal components of high-performance TBCs and depositing them on the inner surface of complex cavities with high aspect ratios. [ABSTRACT FROM AUTHOR]

Perovskite solar cells (PSCs) have attracted widespread attention due to their low cost and high efficiency. So far, a variety of single‐junction PSCs have been successfully developed and considered for commercialization, including normal PSCs (N‐PSCs), inverted PSCs (I‐PSCs), and carbon‐based PSCs (C‐PSCs) without hole transporter. Herein, the material cost, equipment depreciation cost, and energy consumption of these three types of PSCs (1 m2) in detail are analyzed. As indicated, the total fabrication cost of the N‐PSCs ($86.49) and I‐PSCs ($81.31) is very close, but is significantly reduced to $41.16 for the C‐PSCs (49%–52% reduction) because carbon electrode is much cheaper than noble metal electrode and organic hole transporter. Besides, only a low‐cost slot‐die coating process with low energy consumption is needed for the deposition of carbon electrode, while the expensive physical vapor deposition and reactive plasma deposition processes with high energy consumption are needed for the deposition of the noble metal electrode and organic hole transporter. [ABSTRACT FROM AUTHOR]

Cotton fabrics with zinc oxide (ZnO) coating are of significant interest due to their excellent antibacterial performance. Thus, they are widely in demand in the textile industry due to their medical and hygienic properties. However, conventional techniques used to deposit ZnO on fabric require long processing times in deposition, complex and expensive equipment, and multiple steps for deposition, such as a separate process for nanoparticle synthesis and subsequent deposition on fabric. In this study, we proposed a new method for the deposition of ZnO on fabric, using cathodic cage plasma deposition (CCPD), which is commonly used for coating deposition on conductor materials and is not widely used for fabric due to the temperature sensitivity of the fabric. The effect of gas composition, including argon and a hydrogen–argon mixture, on the properties of ZnO deposition is investigated. The deposited samples are characterized by XRD, SEM, EDS, photocatalytic, and antibacterial performance against Staphylococcus aureus and Pseudomonas aeruginosa bacteria. It is observed that ZnO-deposited cotton fabric exhibits excellent photocatalytic degradation of methylene blue and antibacterial performance, specifically when a hydrogen–argon mixture is used in CCPD. The results demonstrate that CCPD can be used effectively for ZnO deposition on cotton fabric; this system is already used in industrial-scale applications and is thus expected to be of significant interest to garment manufacturers and hospitals. [ABSTRACT FROM AUTHOR]

This study investigates carbon-nitrogen thin films as active materials in photocatalytic methanol reforming, addressing the need for eco-friendly fuels with minimal waste and non-metallic photocatalysts. Additionally, it explores the synthesis of these materials using plasma-enhanced chemical vapor deposition (PECVD) from acrylonitrile or acetonitrile. This area has limited prior attention in carbon-nitrogen materials synthesis, particularly with subsequent application in methanol reforming offering potential advancements in clean energy production. The aim is to develop effective, environmentally friendly sources of hydrogen, where photocatalysts play a crucial role. The studies involved also characterization for morphology, and chemical structure. The results confirmed the activity in hydrogen production through methanol reforming, achieving a promising rate of 82 ± 6 μmol h−1 cm−2. [Display omitted] • Facile preparation of carbon-nitrogen films by cold plasma. • Non-metallic carbon-nitrogen catalysts for hydrogen production. • Hydrogen production rate of 32–82 μmol h−1 cm−2 over studied materials. [ABSTRACT FROM AUTHOR]

This investigation conducted an experimental study of flow control in a Mach 2.5 cavity combustor using arc plasma energy deposition (APED), implemented both with and without injection. APED was produced by a pulsed arc discharge plasma actuator at frequencies of 5, 10, 15, and 20 kHz. The objective is to elucidate the influence and underlying mechanisms of APED on the flow dynamics by statistically evaluating time-resolved schlieren images and monitoring pressure fluctuations throughout the control process. The findings indicate that APED significantly modifies the energy distribution across unsteady modes and alters the pressure distribution within the flow field. In scenarios without injection, high-frequency discharge triggers oscillations in the shear layer; the impact of precursor shocks and thermal bubbles diminishes the magnitude and fluctuations of both shear layer-induced and internal shocks. Conversely, in the injection scenario, high-frequency discharge, in conjunction with oscillations of the boundary layer and bow shocks, amplifies the oscillation amplitude and frequency of jet vortex shedding. Additionally, APED intensifies the pulsation and penetration depth of the jet, which is essential for enhancing the mixing efficiency of the incoming flow with fuel. The effectiveness of the control is positively correlated with the actuator's discharge frequency, or its average power, within the confines of this study. [ABSTRACT FROM AUTHOR]

The high toxicity of hydrogen sulfide combined with poor sensitivity at room operating temperature urge for the development of new sensitive materials for sensors complying with this requirement, as well as a fast response and low cost. In this work, we have successfully developed materials for surface acoustic wave (SAW) sensors sensitive to H2S gas that provide a reversible response at room temperature. The sensitive materials were created by plasma-enhanced chemical vapor deposition of a-CH films using methane as a precursor with argon and argon admixed with hydrogen or nitrogen and applied on piezoelectric quartz substrates. Smooth films, with an AFM root mean square below 1.5 nm, were obtained in all cases, although slight topographical variations were noted, depending on the gas types. XPS detected varying degrees of oxidation, indicating that the assisting gases played a crucial role in introducing oxygen-containing functional groups, thus influencing the material's surface chemistry and sensitivity response. A hydrogen plasma treatment was applied on the a-CH deposited sensors as a further sensor preparation step. The hydrogen plasma treatment resulted in significant modifications in the topographical features, including roughness increase and notable variations in the surface aspect ratios, as confirmed through AFM data analysis, which involved advanced pixel height analysis and line profile processing. X-ray photoelectron spectroscopy (XPS) studies indicated the formation of new functional groups, increased defect density, and a significant reduction in electron transitions following hydrogen plasma treatment. The sensors demonstrated a reversible response to H2S gas within 8 to 20 ppm concentration ranges, effectively detecting these levels. The sensitivity of the sensors was significantly enhanced, up to 39% through hydrogen plasma treatment, reaching an improved overall performance in detecting low concentrations of H2S down to 0.9 ppm. These findings highlight a-CH thin films as an excellent candidate for next-generation SAW sensors. The study also suggests the potential for experimenting with various assisting gases during plasma deposition and additional plasma treatments to push detection capabilities to below ppm levels. [ABSTRACT FROM AUTHOR]

Ga2O3 has received increasing interest for its potential in various applications relating to solar-blind photodetectors. However, attaining a balanced performance with Ga2O3-based photodetectors presents a challenge due to the intrinsic conductive mechanism of Ga2O3 films. In this work, we fabricated amorphous Ga2O3 (a-Ga2O3) metal–semiconductor–metal photodetectors through capacitive coupled plasma assisted magnetron sputtering at room temperature. Substantial enhancement in the responsivity is attained by regulating the capacitance-coupled plasma power during the deposition of a-Ga2O3. The proposed plasma energy generated by capacitive coupled plasma (CCP) effectively improved the disorder of amorphous Ga2O3 films. The results of X-ray photoelectron spectroscopy (XPS) and current-voltage tests demonstrate that the additional plasma introduced during the sputtering effectively adjust the concentration of oxygen vacancy effectively, exhibiting a trade-off effect on the performance of a-Ga2O3 photodetectors. The best overall performance of a-Ga2O3 photodetectors exhibits a high responsivity of 30.59 A/W, a low dark current of 4.18 × 10−11, and a decay time of 0.12 s. Our results demonstrate that the introduction of capacitive coupled plasma during deposition could be a potential approach for modifying the performance of photodetectors. [ABSTRACT FROM AUTHOR]

AISI-1045 steel is a medium-carbon, medium-strength steel that usually requires surface engineering to be usable in industrial applications. Using the cathodic cage plasma deposition technique, transition metal (Nb, V, W) nitride coating is deposited on this steel using cathodic cage lids of these metals. The hardness of untreated steel (1.8 GPa) is upgraded to 11.2, 12.2, and 9.7 GPa for niobium nitride, vanadium nitride, and tungsten nitride coating, respectively. The elastic modulus, the ratio of hardness-elastic modulus (H/E, H2/E, and H3/E2), and the plasticity factor depict the improvement in mechanical and elastic properties. The sample treated with a niobium cage lid exhibits the Nb4N5 phase, the vanadium cage lid shows the VN phase (along with the Fe4N phase), and the tungsten cage lid consists of W2N3, WFeN2, and Fe4N phases. Among these coatings, the thickness of niobium nitride coating is maximum (1.87 μm), and a low deposition rate is obtained for tungsten nitride coating (0.83 μm). In addition to this coating, a nitrogen diffusion zone (∼60 μm) is also formed beneath the coating, which creates a hardness gradient between the coating and the substrate. The ball-on-disc wear tester shows that niobium nitride coating deposition reduces the wear rate from 19.5 × 10−3 to 8.8 × 10−3 mm3/N m and exhibits excellent wear performance. [ABSTRACT FROM AUTHOR]

Changes in the interfacial structures of the amorphous silicon (a-Si) anode/organic electrolyte interfaces in lithium-ion batteries were investigated using highly dense a-Si films fabricated by cathodic arc plasma deposition as a model electrode. Raman spectroscopy, transmission electron microscopy (TEM), and X-ray reflectivity revealed that the Si films were grown in an amorphous state with an atomically flat surface. The a-Si films exhibited lithium alloying and de-alloying reactions, with a large irreversible capacity during the first cycle. The irreversible capacity was derived from the formation of a solid electrolyte interphase (SEI) along with an incompletely de-alloyed Li-Si phase, as confirmed by ex situ TEM and X-ray photoelectron spectroscopy observations. The discharge and charge capacities of the Si films gradually decreased in the subsequent cycles, despite the fact that no further SEI formation or cracking of the Si layer occurred. Scanning electron microscopy observations combined with energy-dispersive X-ray spectroscopy revealed the miniaturization of the a-Si film in the surface region to generate domains measuring less than a few hundred nanometers. These results suggest that delamination and miniaturization of the a-Si nanodomains from the electrode surface are partly responsible for degradation of the a-Si anode. [ABSTRACT FROM AUTHOR]

An approach for the agnostic identification and validation of aptamers for the prediction of a medical state from plasma analysis is presented in application to a key risk factor for Alzheimer's disease. brain amyloid deposition. This method involved the use of a newly designed aptamer library with sixteen random nucleotides interspersed with fixed sequences called a Neomer library. The Neomer library approach enables the direct application of the same starting library on multiple plasma samples, without the requirement for pre-enrichment associated with the traditional approach. Eight aptamers were identified as a result of the selection process and screened across 390 plasma samples by qPCR assay. Results were analysed using multiple machine learning algorithms from the Scikit-learn package along with clinical variables including cognitive status, age and sex to create predictive models. An Extra Trees Classifier model provided the highest predictive power. The Neomer approach resulted in a sensitivity of 0.88. specificity of 0.76. and AUC of 0.79. The only clinical variables that were included in the model were age and sex. We conclude that the Neomer approach represents a clear improvement for the agnostic identification of aptamers (Aptamarkers) that bind to unknown biomarkers of a medical state. [ABSTRACT FROM AUTHOR]

[Display omitted] • An insight is provided into control of the one-step rapid formation of wrinkled fractal antibiofouling coatings of polymerized d-limonene films. • The method was analyzed numerically and verified experimentally. • A fundamental insight related to the anti-biofouling properties of the fractal wrinkled surfaces made by plasma deposition. Wrinkled coatings are a potential drug-free method for mitigating bacterial attachment and biofilm formation on materials such as medical and food grade steel. However, their fabrication typically requires multiple steps and often the use of a stimulus to induce wrinkle formation. Here, we report a facile plasma-based method for rapid fabrication of thin (<250 nm) polymer coatings from a single environmentally friendly precursor, where wrinkle formation and fractal pattern development are controlled solely by varying the deposition time from 3 s to 60 s. We propose a mechanism behind the observed in situ development of wrinkles in plasma, as well as demonstrate how introducing specific topographical features on the surface of the substrata can result int the formation of even more complex, ordered wrinkle patterns arising from the non-uniformity of plasma when in contact with structured surfaces. Thus-fabricated wrinkled surfaces show good adhesion to substrate and an antifouling activity that is not observed in the equivalent smooth coatings and hence is attributed to the specific pattern of wrinkles. [ABSTRACT FROM AUTHOR]

Long‐term placement of facial implants requires avoiding the formation of fibrous tissue capsules around the artificial material by creating osteoconductive properties of the surface. Most promising approach is the deposition coatings made of materials very similar to bone mineral components, that is, calcium phosphates such as hydroxyapatite (HAp). As part of the research work, an innovative, cost‐effective atmospheric pressure plasma deposition (APPD) system was used as a low‐temperature coating technology for generating the HAp coatings deposition. Full microstructural characterisation of the coatings using SEM and TEM techniques was carried out in the work. It has been shown that the fully crystalline HAp powder undergoes a transformation during the coatings deposition and the material had a quasi‐sintered structure after deposition. The crystalline phase content increased at the coating/substrate interface, while the surface of the HAp was amorphous. This is a very beneficial phenomenon due to the process of bioresorption. The amorphous phase undergoes much faster biodegradation than the crystalline one. In order to increase the bioactivity of the HAp, Zn particles were introduced on the surface of the coating. The TEM microstructural analysis in conjunction with the qualitative analysis of the EDS chemical composition showed that the binding of the Zn particles within the HAp matrix had diffusive character, which is very favourable from the point of view of the quality of the adhesion and the bioactivity of the coating. In the case of such a complex structure and due to its very porous nature, micromechanical analysis was carried out in situ in SEM, that is, by microhardness measurements of both the HAp matrix and the Zn particle. It was shown that the average value of HAp microhardness was 4.395 GPa ± 0.08, while the average value of Zn microhardness was 1.142 GPa ± 0.02 [ABSTRACT FROM AUTHOR]

The heat flux mitigation during the thermal quench (TQ) by the shattered pellet injection (SPI) is one of the major elements of disruption mitigation strategy for ITER. It's efficiency greatly depends on the SPI and the target plasma parameters, and is ultimately characterised by the heat deposition on to the plasma facing components. To investigate such heat deposition, JOREK simulations of neon-mixed dual-SPIs into ITER baseline H-mode and a 'degraded H-mode' with and without good injector synchronization are performed with focus on the first wall heat flux and its energy impact. It is found that low neon fraction SPIs into the baseline H-mode plasmas exhibit strong major radial plasmoid drift as the fragments arrive at the pedestal, accompanied by edge stochasticity. Significant density expulsion and outgoing heat flux occurs as a result, reducing the mitigation efficiency. Such drift motion could be mitigated by injecting higher neon fraction pellets, or by considering the pre-disruption confinement degradation, thus improving the radiation fraction. The radiation heat flux is found to peak in the vicinity of the fragment injection location in the early injection phase, while it relaxes later on due to parallel impurity transport. The overall radiation asymmetry could be significantly mitigated by good synchronization. Time integration of the local heat flux is carried out to provide its energy impact for wall heat damage assessment. For the baseline H-mode case with full pellet injection, melting of the stainless steel armour of the diagnostic port could occur near the injection port, which is acceptable, without any melting of the first wall tungsten tiles. For the degraded H-mode cases with quarter-pellet SPIs, which have 1 / 4 total volume of a full pellet, the maximum energy impact approaches the tolerable limit of the stainless steel with un-synchronized SPIs, and stays well below such limit for the perfectly synchronized ones. [ABSTRACT FROM AUTHOR]

Semiconductor manufacturing processing can be jeopardized due to process fluctuations, and the degradation of equipment parts can significantly influence process variation. Timely diagnosing equipment faults causing process variations is desired in current high-end product manufacturing. This paper proposes a diagnostic method for the SiH4 gas flow rate drift using N2 vibrational transition in oxide deposition. In this research, optical emission spectroscopy (OES) and quadrupole mass spectrometer (QMS) are employed as condition monitoring sensors serving as a reference model to compare the diagnostic performance for gas flow rate drift. The study observes that the OES model exhibits much higher performance for minor diagnoses of less than 5% drift. The diagnostic model performance can be enhanced by incorporating plasma condition and gas indicators compared to when these indicators are used individually. This suggests that when conducting diagnostics for equipment and processes, it is crucial to consider indirect indicators like plasma indicators along with direct indicators such as gas radical density. The comprehensive use of both types of indicators enhances the diagnostic performance, providing a more accurate assessment of the conditions and potential problem in semiconductor manufacturing. [ABSTRACT FROM AUTHOR]

Macrophages are widely recognized in modulating the foreign body response, and the manner in which they do so largely depends on their activation state, often referred to as their polarization. This preliminary study demonstrates that surface immobilized α-1 acid glycoprotein (AGP), as well as collagen VI (Col6) in conjunction with AGP, can direct macrophages towards the M2 polarization state in vitro and modify the foreign body response in vivo. AGP and Col6 are immobilized onto poly(2-hydroxyethyl methacrylate) (pHEMA) surfaces using carbonyl diimidazole chemistry. Mouse bone marrow derived macrophages are cultured on modified surfaces with or without lipopolysaccharide stimulation. Surface modified pHEMA discs are implanted subcutaneously into mice to observe differences in the foreign body response. After stimulation with lipopolysaccharide, macrophages cultured on AGP or Col6 modified surfaces showed a reduction in TNF-α expression compared to controls. Arg1 expression was also increased in macrophages cultured on modified surfaces. Explanted tissues showed that the foreign body capsule around implants with AGP or AGP and Col6 modification had reduced thickness, while also being more highly vascularized. These data demonstrate that α-1 acid glycoprotein and collagen VI could potentially be used for the surface modification of medical devices to influence macrophage polarization leading to a reduced and modulated foreign body response. [ABSTRACT FROM AUTHOR]

Transparent conductive oxide (TCO) films are widely used as electrodes in photovoltaic devices, such as perovskite solar cells and heterojunction solar cells. However, in the conventional physical vapor deposition process, there may be ion bombardment damage to the underlayer coatings, and high deposition temperature also have an adverse effect on perovskite and amorphous silicon layers during TCO deposition. Herein, reactive plasma deposition was effectively utilized for cerium-doped indium oxide (ICO) film as an ultra-transparent electrode. The effects of plasma gun current and the oxygen ratio on the optical and electrical properties, and also on the structure of the ICO films, were investigated. With an industry-scale reactive plasma deposition tool, an outcome of 140-nm ICO film can be achieved within 50 s, which represents a good throughput with the average growth rate of 2.8 nm/s. When the working current was 165 A and the oxygen ratio was 12%, the average transmittance of ICO films reached the highest value (93.09%) in the wavelength range of 400–1200 nm. The average transmittance in the visible wavelength range was 94.23%. The peak transmittance was up to 99.67% at 515 nm, and the corresponding resistivity was 4.68 × 10−4 Ω cm. [ABSTRACT FROM AUTHOR]

Atmospheric pressure plasma deposition (APPD) of poly(ethylene oxide) (PEO)‐like antifouling coatings provides an attractive way to reduce biofouling for reliable biosensor operation. Cold atmospheric pressure plasma jets are designed to operate in open air. This paper demonstrates the impact of open‐air processing on the composition and properties of PEO‐like coatings by APPD with vinyl ether precursors. The open‐air environment inhibits polymerization as indicated by low deposition rates, oxygen incorporation in the coatings, and instability of the coatings in water. The composition and stability of the coatings improve by appropriate nozzle design and by deposition in an environment with lower air content. The resulting PEO‐like coatings are stable and antifouling for an antibody solution and inhibit adhesion of human fibroblast cells. [ABSTRACT FROM AUTHOR]

Rare-earth silicates have been pursued for many years as candidates for Environmental Barrier Coatings for the protection of silicon carbide (SiC) based components in the new generation of aero and power production turbine engines. The properties and behavior of these materials are usually reported based on theoretical studies or measurements done on bulk specimens, but their prospective use is in the form of coatings. One of the most extended ways of depositing these coatings is plasma spray which produces partially or totally amorphous deposit and changes towards SiO 2 lean chemical composition. In this work is comparatively discussed the effect of plasma spray deposition on Yb 2 Si 2 O 7 , Y 2 Si 2 O 7 and the mixed cation silicate (Y 0.5 Yb 0.5) 2 Si 2 O 7 coatings. The phase evolution with temperature and its impact on the coefficient of thermal expansion, microstructure and thermal conductivity are described. The stability of crystalline phases, properties and absence of cracks in its microstructure makes (Y 0.5 Yb 0.5) 2 Si 2 O 7 a more optimum candidate among the studied rare-earth silicates for environmental barrier applications. [ABSTRACT FROM AUTHOR]

Controlling the wettability properties of metallic materials and surfaces can enhance their applicability and improve their performance and durability in several fields, such as corrosion protection, heat transfer applications, self-cleaning, and friction reduction. Here, we present and compare some versatile fabrication methods that can provide aluminum surfaces with durable superhydrophobic performance which are suitable for heat transfer applications. To probe their stability in heat transfer applications, two evaluation protocols are designed, one which suggests immersion in hot water for several hours, and a second testing against the harsh conditions of hot steam impact. The superhydrophobic aluminum surfaces are fabricated by first creating micro or micro-nano roughness on an initially flat surface, followed by the minimization of its surface energy through two hydrophobization methods, one wet and one dry, thus creating a series of different coating materials. Surfaces are then evaluated by immersing them in hot water and exposing them to steam impact. It is demonstrated that despite the fact that all hydrophobization methods tested resulted in surfaces exhibiting superhydrophobic properties, only the ultra-thin Teflon-like coating, obtained after plasma deposition using C4F8 plasma, exhibited robust superhydrophobicity with hysteresis lower than 8° when immersed in water at 90 °C for 10 h. This surface also showed minimal wettability changes and was the only one to retain its hysteresis below 6° after 4 h of exposure to hot steam. [ABSTRACT FROM AUTHOR]

The deposition of a thin LixSny alloy layer by plasma vapor deposition (PVD) on the surface of a Li foil is reported. The formation of a Li-rich alloy is confirmed by the volume expansion (up to 380%) of the layer and by the disappearance of metallic Sn peaks in the X-ray diffractogram. The layer has a much higher hardness than bare Li and can withstand aggressive cycling at 1C. Post-mortem scanning electron microscope observations revealed that the alloy layer remains intact even after fast cycling for hundreds of cycles. A concept of double modification by adding a thin ceramic/polymer layer deposited by a doctor blade on top of the LixSny layer was also reported to be efficient to reach long-term stability for 500 cycles at C/3. Finally, a post-treatment after Sn deposition consisting of a plasma cleaning of the LixSny alloy layer led to a strong improvement in the cycling performance at 1C. The surface is smoother and less oxidized after this treatment. The combination of a Li-rich alloy interlayer, the increase in hardness at the electrolyte/Li interface, and the absence of dissolution of the layer during cycling at high C-rates are reasons for such an improvement in electrochemical performance. [ABSTRACT FROM AUTHOR]

Oxygen diffusion coefficients in the metastable ferroelectric phase of polycrystalline hafnium zirconium oxide (HZO) thin films have been quantified using 18O tracers and time-of-flight secondary ion mass spectrometry. 11.5 nm thick HZO films containing 16O were deposited by plasma-enhanced atomic layer deposition followed by post-metallization annealing to crystallize into the ferroelectric phase. A 1.2 nm thick HZO layer containing 18O was then deposited using thermal atomic layer deposition with H218O as a reactant. Thermal anneals were conducted at 300, 350, and 400 °C and the ferroelectric phase confirmed after the anneals by x-ray diffraction, infrared spectroscopy, and electrical property measurements. 18O depth profiles were measured and fit with a thin film diffusion equation to determine the oxygen diffusion coefficients. Oxygen diffusion coefficients ranged from approximately 2 × 10−18 cm2/s at 300 °C to 5 × 10−17 cm2/s at 400 °C with an activation energy of 1.02 ± 0.24 eV. [ABSTRACT FROM AUTHOR]

The differentiation of B cells into plasma cells is associated with substantial transcriptional and epigenetic remodeling. H3.3 histone variant marks active chromatin via replication-independent nucleosome assembly. However, its role in plasma cell development remains elusive. Herein, we show that during plasma cell differentiation, H3.3 is downregulated, and the deposition of H3.3 and chromatin accessibility are dynamically changed. Blockade of H3.3 downregulation by enforced H3.3 expression impairs plasma cell differentiation in an H3.3-specific sequence-dependent manner. Mechanistically, enforced H3.3 expression inhibits the upregulation of plasma cell-associated genes such as Irf4, Prdm1, and Xbp1 and maintains the expression of B cell-associated genes, Pax5, Bach2, and Bcl6. Concomitantly, sustained H3.3 expression prevents the structure of chromatin accessibility characteristic for plasma cells. Our findings suggest that appropriate H3.3 expression and deposition control plasma cell differentiation. During plasma cell differentiation, H3.3 histone variant is downregulated, and the H3.3 deposition and chromatin accessibility are dynamically changed. Blockade of H3.3 downregulation by enforced H3.3 expression impairs plasma cell differentiation. [ABSTRACT FROM AUTHOR]

This study investigates the simultaneous decoration of vertically aligned molybdenum disulfide nanostructure (VA-MoS2) with Ag nanoparticles (NPs) and nitrogen functionalization. Nitrogen functionalization was achieved through physical vapor deposition (PVD) DC-magnetron sputtering using nitrogen as a reactive gas, aiming to induce p-type behavior in MoS2. The utilization of reactive sputtering resulted in the growth of three-dimensional silver structures on the surface of MoS2, promoting the formation of silver nanoparticles. A comprehensive characterization was conducted to assess surface modifications and analyze chemical and structural changes. X-ray photoelectron spectroscopy (XPS) showed the presence of silver on the MoS2 surface. Scanning electron microscopy (SEM) confirmed successful decoration with silver nanoparticles, showing that deposition time affects the size and distribution of the silver on the MoS2 surface. [ABSTRACT FROM AUTHOR]

Carbon deposits consisting of vertically oriented multilayer graphene sheets on metallic foils represent an interesting alternative to activated carbon in electrical and electrochemical devices such as super-capacitors because of the superior electrical conductivity of graphene and huge surface–mass ratio. The graphene sheets were deposited on cobalt foils by plasma-enhanced chemical vapor deposition using propane as the carbon precursor. Plasma was sustained by an inductively coupled radiofrequency discharge in the H mode at a power of 500 W and a propane pressure of 17 Pa. The precursor effectively dissociated in plasma conditions and enabled the growth of porous films consisting of multilayer graphene sheets. The deposition rate varied with time and peaked at 100 nm/s. The evolution of surface wettability was determined by the sessile drop method. The untreated substrates were moderately hydrophobic at a water contact angle of about 110°. The contact angle dropped to about 50° after plasma treatment for less than a second and increased monotonously thereafter. The maximal contact angle of 130° appeared at a treatment time of about 30 s. Thereafter, it slowly decreased, with a prolonged deposition time. The evolution of the wettability was explained by surface composition and morphology. A brief treatment with oxygen plasma enabled a super-hydrophilic surface finish of the films consisting of multilayer graphene sheets. [ABSTRACT FROM AUTHOR]

Room temperature quantum emitters have been reported in aluminum nitride grown on sapphire, but until now they have not been observed in epilayers grown on silicon. We report that epitaxial aluminum nitride grown on silicon by either plasma vapor deposition or metal-organic vapor phase epitaxy contains point-like emitters in the red to near-infrared part of the spectrum. We study the photon statistics and polarization of emission at a wavelength of 700–750 nm, showing signatures of quantized electronic states under pulsed and CW optical excitation. The discovery of quantum emitters in a material deposited directly on silicon can drive integration using industry standard 300 mm wafers, established complementary metal-oxide-semiconductor control electronics, and low marginal-cost mass-manufacturing. [ABSTRACT FROM AUTHOR]

Summary: PVD Coatings Enable Textile Wires and Sensors – Process control by adjusted energy ranges Plasma sputtering deposition is a Physical Vapor Deposition (PVD) method based on a weakly ionized gas, the plasma, that ablates atoms from a solid target material at vacuum conditions to deposit the sputtered atoms on a substrate. In this way, the plasma has two functions, i) the generation of high‐energy ions of several 100 eV accelerated to the target for sputtering, and ii) to support film growth by plasma‐surface interaction with particles bearing lower energies around ∼10 eV. For both processes, energy thresholds are present, which will be discussed in this article. Plasma sputtering deposition has wide spread industrial applications. As one example, the metallization of polymer fibers is demonstrated to obtain electrically conductive textile sensors and wires. [ABSTRACT FROM AUTHOR]

The objective of this study was to investigate the modification of glass surfaces by the synergistic combination of cold plasma and chemical surface modification techniques. Glass surface hydrophobicity was obtained as a result of various plasma and deposition operational conditions. The mechanisms governing the hydrophobization process were also studied. Glass plates were activated with plasma using different gases (oxygen and argon) at different treatment times, ranging from 30 to 1800 s. Then, the plasma-treated surfaces were exposed to hexamethyldisilazane vapors at different temperatures, i.e., 25, 60, and 100 °C. Complete characterization, including contact angle measurements, surface free energy calculations, 3D profilometry, X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, and scanning electron microscopy, was accomplished. It was found that the extent of the hydrophobicity effect depends on both the plasma pre-treatment and the specific conditions of the hexamethyldisilazane deposition process. Plasma activation led to the formation of active sites on the glass surface, which promoted the adsorption and reaction of hexamethyldisilazane species, thereby inducing surface chemical modification. Longer plasma pre-treatment resulted in stronger modification on the glass surface, resulting in changes in the surface roughness. The largest water contact angle of ≈100° was obtained for the surface activated by argon plasma for 1800 s and exposed to hexamethyldisilazane vapors at 25 °C. The changes in the surface properties were caused by the introduction of the hydrophobic trimethylsilyl groups onto the glass surface as well as roughness development. [ABSTRACT FROM AUTHOR]

Carbon films were directly formed on tungsten (W) substrates without an intermediate layer via coaxial arc plasma deposition. The substrate surface was pretreated to remove the native oxide films to improve film adhesion using environmentally friendly alkaline and acidic solutions. The fundamental electrochemical characteristics of the deposited films were similar to those of diamond and diamond‐like carbon films. Thus, the deposited films can be used in the electrodes of highly sensitive electrochemical sensors. © 2024 Institute of Electrical Engineers of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Nanosecond repetitively pulsed (NRP) discharges have been considered a promising technique for enhancing combustion efficiency and control. For successful implementation, it is necessary to understand the complex plasma–combustion interactions involving chemical, thermal, and hydrodynamic pathways. This paper aims to investigate the mechanisms enhancing a laminar methane–air flame assisted by NRP discharges by high fidelity simulations of the jet-wall burner employed in a previous experimental study. A phenomenological plasma model is used to represent the plasma energy deposition in two channels: (1) the ultrafast heating and dissociation of O 2 resulting from the relaxation of electronically excited N 2 , and (2) slow gas heating stemming from the relaxation of N 2 vibrational states. The flame displacement, key radical distribution and flame response under plasma actuation are compared with experimental results in good agreement. The computational model allows a systematic investigation of the dominant physical mechanism by isolating different pathways. It is found that the kinetic effect from atomic O production dominates the flame dynamics, while the thermal effect plays a minor role. Hydrodynamic perturbations arising from weak shock wave propagation appear to be sensitive to burner geometry and is found to be less significant in the case under study. [ABSTRACT FROM AUTHOR]

In this study, a one-pot liquid plasma jet technique was explored for the synthesis of silver (Ag) and titania nanoparticles (TiO2 NPs), as well as their effective composite (AgTiO2). Compared to conventional approaches, this approach involves the plasma deposition of Ag NPs onto TiO2 NPs, which is simpler and more eco-safe. The size measurement by XRD analysis revealed the formation of Ag, TiO2, and Ag/TiO2 photo-catalysts with 10 nm, 15 nm, and 17 nm with UV-Vis bandgap energies of 2.58 eV, 3.36 eV, and 2.86 eV respectively. The as-synthesized catalysts were used for the degradation of Methylene blue (MB) and methyl orange (MO) dyes. Ag/TiO2 acted as the best photo-catalyst, with 92.64 % degradation of MB and 77.5 % of MO in just 60 minutes. Integrating Ag onto TiO2 NPs reduced the band gap with inhibited electron-hole recombination, which enhanced its reusability with minimal activity loss. Moreover, the Ag/TiO2 photo-catalyst also showed strong antioxidant activity using the DPPH method. Integrating Ag onto TiO2 significantly enhanced the antibacterial performance against Staphylococcus aureus and Escherichia coli. Overall findings demonstrate the potential of plasma-enhanced integration of Ag NPs onto the TiO2 matrix for effective photocatalytic, antioxidant, and antibacterial applications. [ABSTRACT FROM AUTHOR]

Due to the unique properties of titanium (Ti) and its alloys, it has a particularly wide range of applications in aerospace, automotive, medical and other fields. However, the problems of low surface hardness, high friction coefficient and low wear resistance of Ti alloys limit its development to a certain extent. The destruction of Ti and its alloys often occurs on the surface of materials such as wear damage, corrosion, and oxidation resistance. Therefore, the exploration and application of surface strengthening technology is particularly important. The cathodic plasma electrolytic deposition (CPED) technology, as a surface modification technology, can achieve better adhesion and facilitate the material to achieve better comprehensive performance. This paper briefly introduces the basic concepts, principles and development progress of CPED. Starting from the preparation of ceramic coatings, metal coatings, diamond-like carbon films and composite coatings, it summarizes the application of CPED in Ti and its alloys. Applications in alloys to improve thermal oxidation resistance, wear resistance, corrosion resistance, and film-based adhesion. At the end, its development in the new era environment is prospected. [ABSTRACT FROM AUTHOR]

Plasma-enhanced chemical vapor deposition is a well-developed technique that is commonly applied in the preparation of thin films. However, this technique is limited to thermodynamically stable and chemically inert precursor gases or vapors. Recently, pulsed aerosol-assisted plasma processes have emerged as an advantageous alternative that allows for the injection of various liquid solutions in the plasma, regardless of their properties. This study examines the production of thin films by pulsed injection of pentane aerosols into a low-pressure RF capacitively coupled plasma. This technique produces thin films with high material balance and a high degree of control by adjusting the pulsed injection parameters. At the pulse scale, pulsed injection induces a temporary increase in the working pressure, resulting in time-dependent mechanisms that can affect the dynamics of thin-film deposition at the process scale. Overall, the results show a key role of droplets and their kinetics (ballistic transport, vaporization kinetics, electrostatic confinement). Hence, to efficiently apply this method in the preparation of (multi-)functional coatings, the aerosol must be carefully characterized. [ABSTRACT FROM AUTHOR]

The efficient and prompt mixing of fuel is crucial in the operation of scramjet engines. This paper presents the findings from wind tunnel experiments that examined the influence of plasma energy deposition on transverse jets at a Mach number of 6.13. The study took into account various inlet flow total pressures and momentum flux ratios between the jet and the main flow. Utilizing a database containing time-resolved intensities from instantaneous schlieren images, we perform turbulence analysis employing various techniques such as the root mean square, fast Fourier transform, proper orthogonal decomposition, and the two-point correlation method. Specifically, we aim to compare and analyze the pulsation characteristics and spatial self-organization of the jet flow field, both with and without energy deposition control. The findings reveal that intermittent "hot bubbles" created by plasma energy deposition interact with the bow shock induced by the jet, resulting in the formation of an array of large-scale vortices. These vortices emerge as the dominant structures within the jet, effectively amplifying its pulsations. At low inlet flow pressures, energy deposition primarily disrupts the jet, causing large-scale vortices to propagate primarily within the jet plume region. However, at high inlet flow pressures, the impact of energy deposition extends to both the jet and the turbulent boundary layer, encompassing their respective disturbance ranges. Increasing the inlet flow pressure constraints the evolution of large-scale vortices, thus limiting the efficacy of energy deposition in governing the mixing process. [ABSTRACT FROM AUTHOR]

Among the nondestructive carbon material characterization tools, the prominence of visible Raman spectroscopy has surged remarkably for many years due to its ability to explore a diverse array of carbon bonding configurations. However, to fully unlock the distinctive features concealed within carbon composite materials, additional specimen treatments or precise spectroscope calibrations are necessary. In the same regard, the tiny diamond grain size (5–10 nm) and the pronounced amount of sp2 carbon in the ultrananocrystalline diamond film represent major challenges in visible light excitation. In this work, we employ calibrated oxygen plasma reactive ion etching conditions to manifest the nanodiamond visible Raman signature from ultrananocrystalline diamond/amorphous carbon composite (UNCD/a‐C) films fabricated by coaxial arc plasma deposition. Upon plasma etching, the broad defect band in the visible Raman spectra converged toward the diamond characteristic Raman peak at 1332 cm−1. A detailed explanation of band components of the Raman spectra is extracted through peak fitting procedures. The results of Raman spectroscopy are further correlated with the electrical characteristics of the nitrogen‐doped UNCD/a‐C films due to the optimized oxygen plasma etching processes. [ABSTRACT FROM AUTHOR]

Additive manufacturing techniques offer significant advantages for creating complex components efficiently, saving both time and materials. This makes them particularly appealing for producing parts from intricate alloys, such as Hastelloy C-22. One such technique, plasma metal deposition, uses plasma on powdered material to build up layers. The novelty of this work is to analyze and determine whether there is a correlation between the particle size and the final behaviour of specimens produced via additive manufacturing. To achieve this, four powders with an identical chemical composition but different granulometries were employed. Additionally, some of the samples underwent thermal treatment (progressive heating at 10 °C/min until 1120 °C, maintained for 20 min, followed by rapid air cooling). Four walls were constructed, and after mechanical, tribological, and microstructural characterization, it was determined that the influence of the thermal treatment remained consistent, regardless of particle size. It was observed that the particle size slightly affected the final properties: the finer the powder, the lower the ultimate tensile strength values. Furthermore, it was evident that the thermal treatment substantially affected the microstructure and wear behavior of all the specimens, regardless of their initial particle size. [ABSTRACT FROM AUTHOR]

Hospital-acquired infections (HAIs) remain a significant factor in hospitals, with implant surfaces often becoming contaminated by highly resistant strains of bacteria. Recent studies have shown that electrical plasma discharges can reduce bacterial load on surfaces, and this approach may help augment traditional antibiotic treatments. To investigate this, a cold atmospheric plasma was used to deposit tobramycin sulphate onto various surfaces, and the bacterial growth rate of K. pneumoniae in its planktonic and biofilm form was observed to probe the interactions between the plasma discharge and the antibiotic and to determine if there were any synergistic effects on the growth rate. The plasma-deposited tobramycin was still active after passing through the plasma field and being deposited onto titanium or polystyrene. This led to the significant inhibition of K. pneumoniae, with predictable antibiotic dose dependence. Separate studies have shown that the plasma treatment of the biofilm had a weak antimicrobial effect and reduced the amount of biofilm by around 50%. Combining a plasma pre-treatment on exposed biofilm followed by deposited tobramycin application proved to be somewhat effective in further reducing biofilm growth. The plasma discharge pre-treatment produced a further reduction in the biofilm load beyond that expected from just the antibiotic alone. However, the effect was not additive, and the results suggest that a complex interaction between plasma and antibiotic may be at play, with increasing plasma power producing a non-linear effect. This study may contribute to the treatment of infected surgical sites, with the coating of biomaterial surfaces with antibiotics reducing overall antibiotic use through the targeted delivery of therapeutics. [ABSTRACT FROM AUTHOR]

Plasma-surface modification method (PSMM) is an efficient and inexpensive surface processing method for various materials and has generated great interest in the field of biomedical engineering. This paper focuses on the numerous conventional plasma methods and experimental approaches applied to materials research for suitable biomedical applications, including plasma deposition, laser plasma deposition, plasma sputtering and etching, plasma polymerization, plasma spraying, plasma implantation, and so on. The distinctive benefit of plasma modification is its biocompatibility and surface properties can be enhanced on a selective basis while the bulk characteristics of the materials stay unaltered. Existing materials can hence be used and the requirement for new materials may be circumvented thereby reducing the time for the development of novel and efficient biomedical devices. [ABSTRACT FROM AUTHOR]

The bubble of underwater high current pulsed discharge forms after the pre-breakdown process, and the change in electrical loop parameters will affect its pulsation characteristics. The relationship between loop electrical parameters and the bubble-pulsation process is unclear, and its influence on the acoustic characteristics of the bubble-pulsation is not apparent. In order to quantitatively analyze the bubble-pulsation characteristics, a comprehensive experimental platform of underwater high current pulsed discharge is built. Under different loop electrical parameters, with the help of experimental data of electrical signals and optical images, the variation characteristics of the bubble-pulsation period and energy are analyzed. The acoustic characteristics of the bubble-pulsation process are analyzed, and the correctness of acoustic characteristic analysis is verified by experimental results. The comparison between experimental and theoretical data shows that the analysis of bubble-pulsation period and energy is correct. The bubble-pulsation characteristics can be predicted utilizing the deposition energy of the plasma channel. The results provide a basis for the quantitative analysis of the bubble-pulsation characteristics and strengthen the connection between the three underwater high current pulsed discharge processes. [ABSTRACT FROM AUTHOR]

At present, the research on cathode plasma electrolytic deposition (CPED) mainly focuses on improving the coating properties, while the initial structure and formation mechanism of CPED coating are less studied. This work aims to study the initial deposition behavior of Al 2 O 3 coating by CPED at different time scales systematically. The results show that the coating consists of lamellar Al(OH) 3 in the pre-plasma discharge period. After reaching the breakdown potential, the preparation process of Al 2 O 3 can be considered as a cyclic process: plasma discharge, injection of molten oxide, sintering and solidification, and stacking. Such an iterative process results in a gradual thickening of the coating. Later in the deposition process, the raised structure of the coating surface flaps off and coating thickness decreases. In addition, the high temperature during plasma discharge results in local melting of the substrate surface, which is co-deposited with Al 2 O 3. [ABSTRACT FROM AUTHOR]

Power parameters are of importance to determine the microstructure and property of coatings deposited by cathode plasma electrolytic deposition (CPED). In the present study, the effect of power parameters including voltage and duty cycle on the microstructure and anti-corrosion property of zirconia (ZrO 2) CPED-coatings was investigated. The results suggested that the as-deposited coatings consisted of t -ZrO 2 and m -ZrO 2 , while the content of t -ZrO 2 exceeded 50 %. The content of t -ZrO 2 increased with the increase of voltage and decreased with the increase of duty cycle, reaching a maximum of 89.9 %. In addition, as the voltage and duty cycle increased, the porosity of the coating increased from 3.7 % to 15.5 %. Due to the high t -ZrO 2 content, high thickness and relatively dense structure, the coatings deposited at 250 V had a superior corrosion resistance in 3.5 wt% NaCl solution. This work will provide a guideline for tailoring high performance ZrO 2 CPED-coatings. [ABSTRACT FROM AUTHOR]

A comparative study of bronze coatings on steel produced by plasma and cold metal transfer wire-arc depositing was carried out. The microstructure, interface characteristics, hardness, and shear bond strength of bronze deposits were investigated. Cold metal transition (CMT) deposition presented lesser penetration cracks and lower dilution than that of plasma arc deposition (PAD). The interfacial bonding of CMT deposits appeared as diffusion bonding characteristics, whereas PAD achieved a good metallurgical bond. Plasma arc deposited specimens showed more severe penetrating cracks and less CMT due to the difference of dilution rate. As heat input increased, microstructure of CMT and PAD deposited layer transformed from α-Cu + spherical or dendritic Fe-rich phase to massive Fe-rich phase + ε-Cu. The volume percentage of α-Cu +γ1 in CMT deposits was observed higher than that of PAD, and Fe-rich phase in the PAD was significantly higher than that of CMT, leading in a significant increase of microhardness of PAD. Interfacial bonding strength of PAD under high heat input was much higher than that of CMT. [ABSTRACT FROM AUTHOR]