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Mixed metal oxide (MMO) nanoparticles (NPs) are hybrids consisting of two or more nanoscale metal oxides. Advantages of MMO NPs over single metal oxides include improved catalytic activity, enhanced electrical and magnetic properties, and increased thermal stability due to the synergy of the different oxide components. This study presents a novel fabrication route for TiO2‐CeO2 NPs enriched with oxygen vacancies using a Haberland‐type gas aggregation cluster source. The NPs, deposited from different segmented Ti/Ce targets under varying O2 addition, were examined with respect to final composition, morphology, and Ti, Ce surface oxidation states. Particle formation mechanisms are proposed for the observed morphologies. Additionally, available O2 during deposition and its impact on the formation of defective sites were investigated. Defective sites in TiO2‐CeO2 NPs were analyzed using transfer to X‐ray photoelectron spectroscopy and transmission electron microscopy without contact to ambient oxygen. The incorporation of Ce to the target exhibits synergistic effects on the synthesis process. Segmented Ti/Ce targets enable the deposition of a broad range of mixed oxide NPs with diverse compositions and morphologies at considerably enhanced deposition rates, which is vital for practical applications. The presented fabrication approach is expected to be applicable for a broad variety of MMO NPs. [ABSTRACT FROM AUTHOR]

This article presents a study on influence of Copper Concentration Electrolyte (CCE) and voltage on deposition rate of electroformed Conductive Acrylonitrile Butadiene Styrene (CABS) produced through Fused Deposition Modeling. Additive manufacturing is widely recognized as a rapid production technology. In this research, copper electroforming was selected as subsequent treatment following additive manufacturing. The novelty lies in implementation of pre-treatment process involving electroforming. The pre-treatment process employs carbon conductive paint to render the ABS part conductive. The copper electroforming process involves the use of variable parameters such as electrolyte content of (100, 150, and 200 gram CuSO4 and 50 ml H2SO4) in 1 liter H2O, voltage (1, 2, and 3 Volts), and time (2, 4, 6 and 8 hours). The variables under observation include the copper deposition rate and the microstructure. The analysis of research based on Kruskal-Wallis test. The difference in electrolyte copper concentration and the coating time does not provide significant differences, while the duration of electroforming affects the thickness of the copper deposit. Furthermore, the concentration of copper electrolyte influences the solution’s conductivity, at high concentrations leading to improve conductivity and consequently facilitating a fast deposition rate. The difference in voltage has a significant effect on the deposition rate and microstructure. [ABSTRACT FROM AUTHOR]

Analysis of publications has shown that the use of the exothermic addition with a combined oxidizer (xCuO + (x-1)Fe2O3-Al) as components of filler materials will reduce energy consumption and increase the efficiency of the welding/hardfacing process. However, in the literature, there are no studies of exothermic addition with combined oxidizers, which allow to vary the chemical composition of the deposited metal within a wide range. In this paper, the use of exothermic addition with combined oxidizer (xCuO + (x-1)Fe2O3-Al) was considered. To study the characteristics, standard methods were used to determine the arc stability, melting characteristics, weld bead morphology, melting-energy characteristics, and efficiency parameters, and mechanical properties were made. The structural characteristics were analyzed by optical microscope (OM), X-ray diffractometer (XRD). Microhardness values of the hardfaced samples were obtained using a Vickers hardness tester. The greater stability of arc voltage was shown by the processes performed with flux-cored wires in which oxidizing agents of exothermic addition Al-CuO-Fe2O3 in the core filler were taken with an equal content of oxidizing agents or with a slight excess of oxidizing agent CuO/(CuO + Fe2O3) = 0.5–0.6, whereas the greater stability of the welding current was shown by the processes carried out with the use of flux-cored wire with the exothermic addition with an equal or greater proportion of Fe2O3 oxidizer in the combined oxidizer CuO/(CuO + Fe2O3) ≤ 0.5. Further studies of melting characteristics (deposition rate, spattering factor, etc.), melting-energy characteristics (melt-off coefficient CM and deposition rate coefficient Cd), and efficiency showed the efficiency of using exothermic addition with combined oxidizer of Al-CuO-Fe2O3 system. The study showed high arc stability of the hardfacing process, an increase in deposition efficiency (De), and a decrease in spattering loss, which increased deposition rate from 4.73 kg·h−1 to 6.42 kg·h−1 compared to exothermic addition with simple Al-Fe2O3 system. Analysis of weld bead morphology showed improvement in weld bead parameters. The results showed high energy efficiency and productivity of the welding/hardfacing process with the introduction of exothermic addition with combined oxidizer of CuO-Fe2O3-Al system at the following share of copper oxide in combined oxidizer CuO/(CuO + Fe2O3) = 0.5–0.6. [ABSTRACT FROM AUTHOR]

Metal plating frequently employs nickel (Ni) and copper (Cu) as anodes. Cu/ Cu-Ni film formed has many advantages, such as better corrosion resistance and high hardness characteristics. This study aims to assess the properties of Cu/Cu-Ni film, such as phase, surface morphology, crystallographic orientation, hardness, corrosion analysis, and contact angle, which were fabricated using electrodeposition with various Ni salt additions (0.3, 0.5 and 0.7 M). In addition, the cathode current efficiency (CCE) and deposition rate of the Cu/Cu-Ni electrodeposition were also investigated. An increase in Ni salt in the plating bath could enhance the pH, promoting higher CCE and depleting hydrogen evolution at the cathode, leading to the presenting Ni phase in the alloy. The higher concentration of Ni salt in the solution could also enhance the deposition rate due to a shift to a pH value, which affects the roughening of the surface morphology, promoting a higher contact angle. All crystal structures generated by Cu/Cu-Ni electrodeposition were FCC, with the preferred orientation of the (111) plane. Crystallite size and lattice strain depend on the deposition rate. Less crystallite size and lattice strain affect the film’s hardness and corrosion resistance. Moreover, the third bath had the resulting Cu-Ni layer with the best hardness and corrosion rate of around 136 HV and 0.081 mmpy.

X-rays have high photon energy, which results in a significant penetration depth in ZnO materials. Therefore, in order to detect X-rays effectively, it is necessary to prepare ZnO films with a thickness of micrometers or hundreds of micrometers. In this paper, a 14. 85 μm-thick ZnO film was rapidly prepared by electrochemical deposition method. The experimental results show that the deposition potential and electrode material have a significant effect on the deposition rate and surface morphology of ZnO films. With increasing the deposition potential, the morphology of ZnO changes from hexagonal columnar to lamellar structure. When the potential is too high, a large amount of hydrogen is generated, resulting in an increase in the number of holes in the film that prevent it from forming. When using metal Pt as the anode electrode, the solution will gradually acidify, resulting in the dissolution of ZnO as it is deposited, and when the rates of the two coincide, the ZnO film thickness will no longer increase, making it unsuitable for growing ZnO thick films. In contrast, when using metal Zn as the anode electrode, the pH of the solution remains essentially unchanged, which is more suitable for growing ZnO thick films. A ZnO thick film of 14. 85 μm was grown for 1 h using metallic Zn as the anode electrode with a deposition potential of 0. 65 V and an electrolyte concentration of 0. 4 mol/L. When biased at 5 V, the ZnO thick film based detector has been shown to achieve a responsivity of 66. 8 μC·Gy-1 ·cm-2 to X-rays with an accelerating voltage of 40 kV. [ABSTRACT FROM AUTHOR]

Mixed metal oxide (MMO) nanoparticles (NPs) are hybrids consisting of two or more nanoscale metal oxides. Advantages of MMO NPs over single metal oxides include improved catalytic activity, enhanced electrical and magnetic properties, and increased thermal stability due to the synergy of the different oxide components. This study presents a novel fabrication route for TiO2‐CeO2 NPs enriched with oxygen vacancies using a Haberland‐type gas aggregation cluster source. The NPs, deposited from different segmented Ti/Ce targets under varying O2 addition, were examined with respect to final composition, morphology, and Ti, Ce surface oxidation states. Particle formation mechanisms are proposed for the observed morphologies. Additionally, available O2 during deposition and its impact on the formation of defective sites were investigated. Defective sites in TiO2‐CeO2 NPs were analyzed using transfer to X‐ray photoelectron spectroscopy and transmission electron microscopy without contact to ambient oxygen. The incorporation of Ce to the target exhibits synergistic effects on the synthesis process. Segmented Ti/Ce targets enable the deposition of a broad range of mixed oxide NPs with diverse compositions and morphologies at considerably enhanced deposition rates, which is vital for practical applications. The presented fabrication approach is expected to be applicable for a broad variety of MMO NPs.

Introduction. The use of restored parts of motor vehicles makes it possible to reduce the financial costs of repairing equipment. The cost of the restored parts should not exceed 50% of the cost of the new part. Increasing the productivity (deposition rate) of an electrolytic copper coating during the restoration of parts of motor vehicles requires taking into account the technological and economic aspects of the restoration process. The study of the factors (deposition conditions) that most affect the deposition process of the copper coating, the analysis of the experimental results and its statistical processing made it possible to optimize the technology of restoration of copper parts to create the most appropriate deposition modes with maximum productivity, thus reducing the cost of restoration of parts of motor vehicles. The purpose of the research is to develop a mathematical model of the effect of deposition conditions (electrolyte temperature, cathode current density) and electrolyte composition (concentration of copper sulfate and sulfuric acid) on the performance of the deposition process of copper coating, for further development of the most productive technology for restoring collectors of electric motors of motor vehicles.Materials and methods. The studies on equipment that allows obtaining the necessary data with the required accuracy were carried out. Mathematical processing using modern statistical data processing tools that excluded possible errors, providing to obtain the dependence of factors with the necessary accuracy was carried out.Results. In the course of studies of copper sulfate electrolytes to obtain an electrolytic copper coating, with the further development of technology for the restoration of automotive parts, it became necessary to determine the effect of deposition conditions – “factors” (cathode current density, electrolyte temperature, copper sulfate concentration, sulfuric acid concentration) on the deposition rate – “response”. It was found that the factor “cathode current density” and the combination of factors “cathode current density” and “sulfuric acid concentration” are the most significant. The deposition conditions in order to obtain the most productive technology for restoring collectors of electric motors of motor vehicles by depositing a copper coating have been optimized. According to the obtained model, the optimal values of the deposition conditions for obtaining the maximum deposition rate are the electrolyte temperature of 35...40 ° C, the cathode current density of more than 5 A/Dm2, the concentration of copper sulfate 200...250 g/l, the concentration of sulfuric acid 40...70 g/l.

During the operation of nuclear fusion reactors, plasma-facing components lining the reactor vessel are continually bombarded by plasma species. The penetration and subsequent trapping of these bombarding plasma ions has implications for component damage as well as in-vessel inventory. Accurately predicting the expected ion penetration depth profiles at a range of plasma ion and surface temperatures typical of fusion reactor operating conditions will inform the scrape-off layer design to limit particle radiation damage and tritium trapping in order to prolong the lifetime of the plasma-facing components and satisfy the DT fuel cycle requirements. By defining a statistical distribution for ion penetration depth and describing the evolution of its parameters across the fusion parameter space of interest, the expected ion deposition depth profiles can be calculated for any subset of ion and surface temperature ranges as needed. Molecular dynamics simulations were used to study the bombardment of beryllium lattices with surface temperatures of up to 1100 K by 5 eV–150 eV deuterium and tritium ions, and the resulting ion penetration depths were investigated. The distributions of two penetration depth quantities, considered from the perspectives of lattice damage and hydrogen retention are defined and their distribution parameter dependence on surface and ion temperature is identified. The expected positive correlation between penetration depth and ion temperature is observed, where the non-linear relationship between these quantities indicates the expected form of the velocity dependence of nuclear stopping power at low bombardment energies. Isotope effects on the distributions are also investigated, with results suggesting that heavier ions have comparably lower mobility within the sample and will generally accumulate closer to the surface. A short study on ion deposition rates is also performed; a non-linear increase of deposition rate with increasing bombarding ion energy has been observed, and evidence of a weak positive surface temperature correlation has been noted. [ABSTRACT FROM AUTHOR]

InAs quantum dots were prepared on the surface of GaAs (001) substrate by droplet epitaxy. The effects of deposition rate and deposition amount on the growth of In droplets on GaAs surface were studied by controlling variables. Atomic force microscope was used to characterize the morphology of InAs nanostructures, and it was concluded that: (1) The deposition rate mainly controls the density of the droplets by affecting the nucleation rate of In droplets, that is, with the increase of the deposition rate, the nucleation rate of In atoms on the surface of the substrate increases, and the density of InAs quantum dots increases, experiments are consistent with classical nucleation theory of growth kinetics. (2) The change of deposition amount mainly affects the ripening process of droplets, that is, with the increase of deposition amount, the number of active In atoms that can participate in growth increases, which promotes droplet ripening, increases the number of diffusion collapsed atoms, and thus leads to an increase in the number of atoms in diffusion collapse. Multiple quantum dots appear in InAs nanostructures. [ABSTRACT FROM AUTHOR]

The connection form of pipelines has an important impact on the comprehensive performance evaluation of fresh air systems. The most used PVC fresh air pipeline material in the market was selected for experimental research in this paper, and the deposition rates of particles of different pipeline connection form of 45°, 90° bend, and straight tee were all tested and compared. The purification effect of the pipeline connection form of the highest deposition rate is tested and studied. The results showed that the particle deposition rates were the highest in the connection form of straight tee, with deposition rates of 47.61%, 18.06%, and 8.13% for PM10, PM2.5, and PM1.0, respectively. As the particle size increases, the deposition rate of particles also gradually increases. The larger the inlet velocity, the greater the deposition rate. The particle concentration on the outlet of the pipeline in the connection forms of straight tee was significantly decreased after adding the purification equipment, and the deposition rates of PM10, PM2.5, and PM1.0 decreased by 45.01%, 68.89%, and 77.48%. Therefore, the use of pipeline elbows should be reduced, and purification equipment should be installed in the process of using, which will reduce the deposition of particles in the fresh air systems. [ABSTRACT FROM AUTHOR]

Antimonene has attracted much attention due to its excellent characteristics of high carrier mobility, thermoelectric properties and high stability. It has great application prospects in Q-switched lasers, laser protection and spintronics. At present, the epitaxy growth of antimonene mainly depends on molecular beam epitaxy. We have successfully prepared antimonene films on silicon, germanium/silicon substrates for the first time using electron beam evaporation coating and studied the effects of the deposition rate and substrate on the preparation of antimonene; film characterization was performed via confocal microprobe Raman spectroscopy, via X-ray diffraction and using a scanning electron microscope. Raman spectroscopy showed that different deposition rates can lead to the formation of different structures of antimonene, such as α phase and β phase. At the same time, it was found that the growth of antimonene is also affected by different substrates and ion beams. [ABSTRACT FROM AUTHOR]

In the pursuit of refining the fabrication of three-dimensional (3D) microelectrode arrays (MEAs), this study investigates the application of ultrasonic vibrations in template-assisted electrodeposition. This was driven by the need to overcome limitations in the deposition rate and the height uniformity of microstructures developed using conventional electrodeposition methods, particularly in the field of in vitro electrophysiological investigations. This study employs a template-assisted electrodeposition approach coupled with ultrasonic vibrations to enhance the deposition process. The method involves utilizing a polymeric hard mask to define the shape of electrodeposited microstructures (i.e., micro-pillars). The results show that the integration of ultrasonic vibrations significantly increases the deposition rate by up to 5 times and substantially improves the uniformity in 3D MEAs. The key conclusion drawn is that ultrasonic-enhanced template-assisted electrodeposition emerges as a powerful technique and enables the development of 3D MEAs at a higher rate and with a superior uniformity. This advancement holds promising implications for the precision of selective electrodeposition applications and signifies a significant stride in developing micro- and nanofabrication methodologies for biomedical applications. [ABSTRACT FROM AUTHOR]

The present research reports an experimental study of Ni-W-P-nanoTiO2 composite coatings deposited on API X60 low-carbon steel by the electroless method. Electroless bath parameters are optimized to attain maximum deposition rate using the Taguchi design (L9 orthogonal array). Analysis of variance was performed to find out the significance of individual parameters. A confirmation test was performed at the initial and optimal parameter combination obtained from the Taguchi analysis. In addition, the applicability of artificial neural network (ANN) was also examined for the prediction of deposition rate. An ANN 4-7-1 network accurately predicted the deposition rate with a correlation coefficient (R2) valued at 0.9820. Atomic force microscopy and field emission scanning electron microscopy were used to characterize the surface morphology, and energy-dispersive spectroscopy, and X-ray diffraction were used for compositional and phase study of the coatings. The corrosion behavior of nanocomposite coatings was tested in 3.5 wt% NaCl solution by potentiodynamic polarization. The optimum combination was achieved with 24 g/L of reducing agent content, 10 g/L of TiO2 nanoparticles content, bath pH of 9, and a temperature of 80 °C. [ABSTRACT FROM AUTHOR]

As deep gas-condensate reservoirs are explored, the problem of paraffin deposition is becoming more prominent. Therefore, this paper collects condensate samples from representative paraffin deposition gas-condensate wells and analyzes basic physical properties. The cold plate deposition device is employed to study paraffin deposition behavior under well conditions and to divide the critical regions for paraffin deposition in gas-condensate wells. The experimental apparatus, such as the crude oil dynamic paraffin deposition rate tester, is utilized to investigate the preventive effect of paraffin dispersants and paraffin crystal modifier. The results show that there is significant phase change behavior in gas-condensate wells and gas phase is dominant form, but there is also phase evolution. It can be identified from the experiments that paraffin deposition is mainly located in the 1000 ~ 1500 m region, and a paraffin deposition identification chart has been established. The maximum deposition rate could reach 15.50 mm/year, which matched the temperature and pressure conditions of 45 ℃ and 70 MPa. The preventive effect of paraffin crystal modifiers greatly exceeds that of paraffin dispersants, with paraffin prevention rates of 85–95% at the optimal concentrations of 0.25–0.50 wt.%. The dissolving paraffin rate can reach 0.0169 g/min. It decreases the paraffin appearance temperature approximately 40% and significantly changes the paraffin crystal morphology. Increased deposition surface area of the cold plate structural design describes the paraffin deposition. This diagram facilitates the reliable identification of paraffin deposition areas and the deposition rates in the wellbore during production. The optimum amounts of BZ and PI paraffin inhibitors are quantified. This study provides a comprehensive understanding of the paraffin deposition behavior, and scientific basis and guidance for the selection of paraffin inhibitors in gas-condensate wells. [ABSTRACT FROM AUTHOR]

To improve wear resistance and adhesion, a hard film of titanium carbide (TiC) is usually prepared by a plasma chemical vapor deposition technique. Microwave sheath–voltage combination plasma (MVP) is a method to generate high–density plasma. In the present study, TiC coatings were prepared by MVP and the processing conditions were examined to reveal the effect on film deposition speed. The TiC coatings were deposited in a reactor using a TiCl4–CH4–H2–Ar gas mixture. The phase identifications, binding energy analysis, coating composition, and friction coefficient were investigated by X–ray diffraction (XRD), X–ray photoelectron spectroscopy (XPS), energy dispersive X–ray spectroscopy (EDX), and ball–on–disk friction tester, respectively. TiC was detected by XRD. As the flow rate of the raw material gas increased, the film deposition rate increased. The maximum deposition rate of the films was 9.0 µm/h. By changing the film deposition conditions, it is considered that higher speed film deposition of TiC will be possible. [ABSTRACT FROM AUTHOR]

The cable-type welding wire (CWW) submerged arc surfacing (SAS) is an innovative welding process with the advantages of high efficiency, energy saving, and good welding quality. At present, this welding process has been applied to repair the large structure. This study investigate the arc heat efficiency and arc heat distribution of CWW SAS using the mathematical calculation method. The deposition rate and the surfacing layer area of CWW SAS increases with the increasing welding current. The deposition rate and the surfacing layer area of CWW SAS are larger than those in single-wire SAS. The ratio of the surfacing layer area between CWW SAS and single-wire SAS is similar to the ratio of the surfacing deposition rates between CWW SAS and single-wire SAS. The efficiency of the arc heat on melting wire in CWW SAS is larger than that in single-wire SAS. The arc heat working on base metal in CWW SAS is lower than that in single-wire SAS, leading to a smaller molten base metal area. The arc heat working on droplet transfer in CWW SAS is greater than that in single-wire SAS, leading to a larger surfacing area. [ABSTRACT FROM AUTHOR]

In this paper, the effects of nitrogen flow rate on the physical and chemical properties of TiAlN thin films deposited from magnetron discharge plasma at different power modes have been investigated. A mixed Ti0.5Al0.5 target (50/50 at % element content) was mounted on the magnetron. Stainless steel and silicon wafers were used as substrates. The TiAlN films were obtained by magnetron sputtering with a constant argon flow (0.725 cm3/s). Two groups of TiAlN coatings were obtained at different magnetron powers. For the first and second groups, the power of the magnetron was 1.5 and 1 kW, respectively. A nitrogen flow for each group of samples varied from 0.125 to 0.5 cm3/s in 0.125 cm3/s increments. Changes in the surface morphology, microstructure, nanohardness, and content of Ti, Al, and N in the obtained films (in at %) were studied. The measurements were performed on an S-3400N SEM, a CSM Instruments hardness tester, and Zeiss Supra 55 (In-Lens detector type, electron energy of 10 keV) with a Raith150 Two electron-beam exposure unit. [ABSTRACT FROM AUTHOR]

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The accident at the Fukushima Daiichi Nuclear Power Plant in 2011 led to a core meltdown, resulting in the significant release of radioactive materials into the environment, revealing the urgent need for further in-depth development of Level 2 probabilistic safety assessment technology. To help establish an effective source-term migration evaluation method, this study investigates fission product migration behavior across leak pathways. Specifically, an experimental line is developed, and experiments are performed under conditions that simulate the environmental and flow conditions in containment vessel penetrations and failure locations during a severe accident. The experiments are conducted in narrow circular pipes, which represent the leak pathways in the containment vessel and reactor building, to determine the impact of flow rate, particle size, and flow path size on the decontamination factors. Additionally, a turbulent deposition model that accounts for re-entrainment effects has been developed, and the experimentally obtained decontamination factors are compared with the developed model, as well as a conventional model. The predicted decontamination factors from the present model exhibit similar trends and values to the experimental results.

Abstract As deep gas-condensate reservoirs are explored, the problem of paraffin deposition is becoming more prominent. Therefore, this paper collects condensate samples from representative paraffin deposition gas-condensate wells and analyzes basic physical properties. The cold plate deposition device is employed to study paraffin deposition behavior under well conditions and to divide the critical regions for paraffin deposition in gas-condensate wells. The experimental apparatus, such as the crude oil dynamic paraffin deposition rate tester, is utilized to investigate the preventive effect of paraffin dispersants and paraffin crystal modifier. The results show that there is significant phase change behavior in gas-condensate wells and gas phase is dominant form, but there is also phase evolution. It can be identified from the experiments that paraffin deposition is mainly located in the 1000 ~ 1500 m region, and a paraffin deposition identification chart has been established. The maximum deposition rate could reach 15.50 mm/year, which matched the temperature and pressure conditions of 45 ℃ and 70 MPa. The preventive effect of paraffin crystal modifiers greatly exceeds that of paraffin dispersants, with paraffin prevention rates of 85–95% at the optimal concentrations of 0.25–0.50 wt.%. The dissolving paraffin rate can reach 0.0169 g/min. It decreases the paraffin appearance temperature approximately 40% and significantly changes the paraffin crystal morphology. Increased deposition surface area of the cold plate structural design describes the paraffin deposition. This diagram facilitates the reliable identification of paraffin deposition areas and the deposition rates in the wellbore during production. The optimum amounts of BZ and PI paraffin inhibitors are quantified. This study provides a comprehensive understanding of the paraffin deposition behavior, and scientific basis and guidance for the selection of paraffin inhibitors in gas-condensate wells.

Nowadays, surface modification techniques are a big part of making metals and alloys better on the outside. Even though various metals and alloys are coated using surface modification techniques, improving the surface properties of the light alloys is difficult. To improve the surface properties of light alloys, electro-thermal techniques, namely electro discharge deposition (EDD), are suitable. Hence, in this investigation, a fly ash (FA)–copper (Cu) composite coating was developed on AA7075 using electro discharge deposition. The FA–Cu composite electrodes were manufactured by the powder metallurgy method. The effects of discharge current, pulse on time, and pulse off time on deposition rate (DR) and coating roughness (CR) have been studied. Tests were carried out according to the design matrix generated by central composite design in response surface methodology (RSM). An ANOVA was performed to determine the optimum parametric conditions for the responses. Pulse off time was the dominating parameter followed by discharge current and pulse on time for attaining the best response. Higher values of current, pulse on time, and pulse off time led to higher DR and CR values. Higher discharge current produced sufficient spark strength that melted both the tool electrode and the workpiece. The lower setting of parameters offered smooth roughness due to the even spark distribution. At a current of 8 A, bigger craters were observed due to the higher spark intensity that made the surface hard. The uneven mass was produced with a deeper shallow crater, resulting in a poor surface.

This paper is the second part of a work focused on optimizing the performance of conventional Laser Metal Deposition (C-LMD) process for Inconel 718 (IN718). In Part I, through an extensive experimental campaign on single tracks, the interplay between process parameters and their impact on the deposition rate, powder catchment efficiency, and clad geometry is examined. The parameters investigated include laser power, scan speed, powder feed rate, and standoff distance. By systematically adjusting these parameters, the aim is to identify optimal conditions that maximize productivity while maintaining a favorable clad shape for multi-pass multi-layer depositions. Part II starts from the findings and results of Part I by continuing the optimization on thick wall structures. These are utilized to assess the effect of 3D geometrical process parameters, specifically hatch spacing and Z-step, on process performance and stability. Based on the findings, further optimization procedure is presented, pushing the boundaries of the C-LMD process for IN718. By fine-tuning the process parameters, the capability of the C-LMD process to deposit fully dense IN718 with a productivity of 1500 g/h and a powder catchment efficiency of 70% is demonstrated. These results highlight the potential of C-LMD as a viable manufacturing technique for efficiently fabricating large components. Overall, this study contributes to a deeper understanding of the relationship between process parameters and performance in C-LMD for IN718. The insights gained from this research can guide the development of efficient and cost-effective LMD strategies, facilitating the practical implementation of this process in various industries. [ABSTRACT FROM AUTHOR]

In the flexible photovoltaic (PV) industry, increment of the metal‐organic chemical vapor deposition (MOCVD) deposition zone is crucial to reducing the cost of ownership and increasing the power conversion efficiency (PCE). This implies that the larger closed coupled showerhead (CCS) of MOCVD system should be used in the manufacture of flexible gallium arsenide (GaAs) PV thin‐film solar cells. Currently, Aixtron Crius II is the largest commercial CCS reactor for GaAs deposition with 55 × 2 inches circular wafers. As the size of the carrier and showerhead increases, the deposition uniformity and gas flow stability become more difficult to control. To address these issues, previous studies have investigated the effects of geometric and process parameters of MOCVD on the vertical process gas inlet, with either a rotating carrier model represented by Veeco using high‐speed rotating carrier (Turbo Disc), and Aixtron using low‐speed rotating planetary carrier, or a horizontal process gas injector with a rotating carrier. However, these efforts have limited further capacity scale‐up. In this study, numerical simulations and fluid visualization experiments are conducted, based on previous research on thermal uniformity, for design optimization of a gas distribution system in a large square GaAs‐MOCVD reactor. The achieved reactor capacity is 36 × 4 inches square wafers in one process cycle, and the optimal average deposition rate and deposition uniformity of GaAs film are ≈0.430 µm min−1 and 0.93%, respectively. [ABSTRACT FROM AUTHOR]

The CMT-Twin-based wire and arc additive manufacturing (WAAM) process for 5356 aluminium alloy has been investigated focusing on the optimisation of welding parameters to maximise the deposition rate while avoiding segregation-related problems during solidification. For that, different conditions have been studied regarding interpass dwell time and the use of forced cooling. The larger heat input produced by the double-wire CMT-Twin process, compared to the single-wire CMT, creates vast segregations for less intensive cooling conditions and short dwell times that can induce cracks and reduce ductility. Thermography has been applied to set a maximum local temperature between consecutive layers avoiding those segregations and pores, and to optimise the total manufacturing time by varying the interpass dwell time along the height of the wall. Only a constant interpass long dwell time of 240 s and the new optimised strategy were effective in avoiding merged segregations, reducing the latest total manufacturing time by 36%. Obtained tensile properties are comparable to other works using WAAM for this alloy, showing lower properties in the vertical orientation. The use of CMT-Twin-based welding technology together with variable interpass dwell time controlled by thermography is an interesting alternative to build up parts with wall thicknesses around of 10 mm in a reduced time. [ABSTRACT FROM AUTHOR]

The sustainable energy transition has spurred the development of technologies that minimize material and energy waste, such as additive manufacturing (AM). Laser metal deposition (LMD) is a promising AM technique, but its complexity and limited automation hinder its implementation in production chains. To enhance productivity, the high deposition rate LMD (HDR-LMD) technology has been developed, requiring advanced equipment and powerful laser sources. In contrast, the conventional LMD (C-LMD) process is simpler and less expensive to implement. This study aims to optimize the productivity and efficiency of C-LMD by adjusting laser power, scan speed, powder feed rate, and standoff distance on Inconel 718 single tracks. An innovative approach eliminates the need for cutting specimens to evaluate single tracks, allowing comprehensive geometric and performance characterization with limited operator involvement, making the analysis quicker and more robust. An extensive experimental campaign was conducted to examine the influence of process parameters on track geometry, productivity, and efficiency. A multi-objective optimization procedure identified parameter combinations maximizing productivity while maintaining high efficiency and desirable clad shape. The study attained deposition rates ranging from 700 to 800 g/h, with powder catchment efficiency ranging between 75 and 90%. These results were achieved using parameters including 1775 W of laser power, scan speeds ranging from 960 to 1140 mm/min, powder feed rates between 810 and 1080 g/h, and standoff distance of 9 mm. The study also clearly indicated that further potential for improving C-LMD process performance may be possible. The findings gathered in this paper are the base for the further optimization presented in the second part of the work, which is focused on multi-pass multi-layer and reaches deposition rates of 1500 g/h, promoting the implementation of C-LMD process at industrial level. [ABSTRACT FROM AUTHOR]

Magnetron sputtering of an yttrium target in a reactive atmosphere of Ar + O2 enhanced by a radio-frequency inductively coupled plasma source was studied. Four different schemes for yttrium target sputtering were examined to define the possibility to use the metallic deposition mode for a coating consisting of the yttrium oxide phase. The effective pumping speeds were calculated for all experimental schemes. The increase in the effective pumping speed from 0.24 to ~0.87 m3/s when using dual magnetron sputtering of Y and Cu targets was shown to result in the shift of the hysteresis loop towards higher O2 flow rates. This leads to the use of both transition and metallic modes of Y target sputtering in the Ar + O2 atmosphere. The oxide coating was deposited by dual magnetron sputtering of yttrium and copper targets in the metallic mode, enhanced by a radio-frequency inductively coupled plasma source. The coating consisted of Cu2O and Y2O3 phases. The calculation of Cu and Y sputtering yields was done to confirm the metallic mode of coating deposition. [ABSTRACT FROM AUTHOR]

Silicon nitride shows significant potential in the field of surface protection for electronic devices owing to its excellent insulation performance and mechanical properties. In this study, silicon nitride films were fabricated via halide laser chemical vapor deposition (LCVD). The effects of deposition parameters on the crystallinity, microstructure, deposition rate (R dep), Vickers microhardness, nano-hardness and electrical resistivity were investigated. The maximum R dep of the silicon nitride thick films was 972 µm/h at T dep of 1573 K and P tot of 10 kPa, which is the highest value compared with those obtained via conventional CVD. As T dep increased, the Vickers microhardness and nano-hardness of the films increased to the highest value of 25.1 GPa and 34.8 GPa at 1573 K, respectively. The electrical resistivity of the films decreased with increasing T dep and showed a maximum value of 1.49 × 1014 Ω·cm at T dep of 1273 K. [ABSTRACT FROM AUTHOR]

A great focus is currently being placed on the development of applications of Wire Arc Additive Manufacturing (WAAM) in structural engineering. To facilitate this development, an experimental programme investigating the effects of the deposition rate on WAAM 316LSi stainless steel outstand elements has been conducted. Equal angle section (EAS) stub columns with four different cross‐sectional slendernesses were produced using WAAM. For each slenderness, four different deposition rates were employed; hence, overall, sixteen EAS stub columns were produced, 3D scanned and tested to examine their local stability. To keep the heat input constant between all cases, for each deposition rate, the travel speed was varied accordingly. Alongside the EAS specimens, tensile coupon testing was conducted to determine the material properties corresponding to each deposition rate. The tensile coupons were extracted at three different orientations (0°, 45° and 90°) relative to the deposition direction in order to investigate the degree of material anisotropy. In the present paper, following the description of the EAS stub column test results, the applicability of current Eurocode design rules and the Continuous Strength Method for the prediction of their design strength is assessed. [ABSTRACT FROM AUTHOR]

Abstract Thermal barrier coating (TBC) resistance to varied CMAS deposition rates was experimentally assessed using a temperature gradient rig using a CMAS precursor spray. TBCs were composed of EB-PVD YSZ. Five different deposition rates were tested quantifying life versus deposition rate. A high deposition rate and low deposition rate were selected from those tests for sequence testing. For sequence effect testing CMAS deposition occurred at the initial rate until the expected half-life and then switched to the other rate until failure, in the order of high deposition rate first followed by low deposition rate and vice versa. The results suggest that the order of deposition rates can affect ultimate failure behavior. Specifically applying the CMAS at the low deposition rate extended the life of the sample by a nearly a factor of 2 compared to a virgin sample. At the high deposition rate, the CMAS infiltrated all the way to the bond coat past the estimated freeze line. Data showing the coating life versus CMAS deposition rate and the existence of sequence effects in CMAS dosing are fundamentally important to coating life prediction.

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Nowadays, surface modification techniques are a big part of making metals and alloys better on the outside. Even though various metals and alloys are coated using surface modification techniques, improving the surface properties of the light alloys is difficult. To improve the surface properties of light alloys, electro-thermal techniques, namely electro discharge deposition (EDD), are suitable. Hence, in this investigation, a fly ash (FA)ecopper (Cu) composite coating was developed on AA7075 using electro discharge deposition. The FAeCu composite electrodes were manufactured by the powder metallurgy method. The effects of discharge current, pulse on time, and pulse off time on deposition rate (DR) and coating roughness (CR) have been studied. Tests were carried out according to the design matrix generated by central composite design in response surface methodology (RSM). An ANOVA was performed to determine the optimum parametric conditions for the responses. Pulse off time was the dominating parameter followed by discharge current and pulse on time for attaining the best response. Higher values of current, pulse on time, and pulse off time led to higher DR and CR values. Higher discharge current produced sufficient spark strength that melted both the tool electrode and the workpiece. The lower setting of parameters offered smooth roughness due to the even spark distribution. At a current of 8 A, bigger craters were observed due to the higher spark intensity that made the surface hard. The uneven mass was produced with a deeper shallow crater, resulting in a poor surface. [ABSTRACT FROM AUTHOR]

In the present study, we have investigated the impact of the molar concentration of the precursor solution on structural and optical properties of CuO thin films, deposited by air-pressurized spray pyrolysis technique. A set of CuO thin films samples were prepared with various molar concentrations ranging from 0.01 to 0.2 M at a substrate temperature of 300 °C. The film's structure and morphology were characterized by means of X-ray diffraction and scanning electron microscope. The film's optical properties were studied using photoluminescence spectrophotometer (PL) and UV–visible spectroscopy. The obtained results indicate that molar concentration of the precursor solution is a key parameter for controlling the growth mechanism additional to the structural, optical and morphological properties of CuO thin films. An increase in molar concentration leads to an increment in the deposition rate and a reduction in the disorder of the films. [ABSTRACT FROM AUTHOR]

In parabolic trough technology, the development of thermally and structurally stable solar coatings plays a key role in determining the efficiency, durability, and economic feasibility of tube receivers. A cermet-based solar coating is typically constituted by a thin film stratification, where a multilayer graded cermet is placed between an infrared metallic reflector and an antireflection filter. This work reports the realization of materials based on Al2O3 and W characterized by high structural and chemical stability in vacuum at high temperature, obtained through the optimization of high-deposition-rate processes. Al2O3 material, employed as the antireflection layer, was deposited through a reactive magnetron sputtering process at a high deposition rate. Cermet materials based on W-Al2O3 were deposited and employed as absorber layers by implementing reactive magnetron co-sputtering processes. An investigation into the stability of the realized samples was carried out by means of several material characterization methods before and after the annealing process in vacuum (1 × 10−3 Pa) at high temperature (620 °C). The structural properties of the samples were evaluated using Raman spectroscopy and XRD measurements, revealing a negligible presence of oxides that can compromise the structural stability. Spectrophotometric analysis showed little variations between the deposited and annealed samples, clearly indicating the high structural stability.

The SiC coating prepared on graphite substrate can effectively solve the corrosion and powder loss problems of graphite material in environments with high temperature and corrosive gas. In this paper, a SiC coating was prepared on the surface of graphite substrate. The deposition process parameters were adjusted and optimized to realize rapid manufacturing of high - performance SiC coating with the aim of providing theoretical basis and technical support for SiC coating’ application on the surface of graphite substrate. An industrial - grade chemical vapor deposition equipment was employed to prepare the silicon carbide coating on the surface of graphite substrates using methyl trichlorosilane (MTS) and H2 as raw materials. The effects of furnace pressure and sample position on the microstructure and thermal fatigue resistance of the coating were studied by analysis and testing methods such as scanning electron microscopy, X - ray diffractometer and vacuum thermal cycling. Results showed that when the furnace pressure was 2.0 kPa, a high - purity silicon carbide coating with single grain growth orientation could be prepared. As the furnace pressure increased, the deposition rate and thermal fatigue resistance of the coating both showed a non - monotonic change of first rising, then falling and then rising again. When the furnace pressure was 2.0 kPa, the silicon carbide coating had the highest deposition rate and the best thermal fatigue resistance. The coatings prepared with different sample positions were all pure SiC coatings, and the closer the substrate suspension position to the air distribution plate, the faster the coating deposition rate was and the better thermal fatigue resistance the coating showed. When the furnace pressure was 2.0 kPa and the sample position was 300 mm, a SiC coating with good thermal fatigue resistance could be quickly prepared.

In this work, the antireflective nanostractured ITO/Al2O3 coatings that have a gradient of the effective refractive index in the direction perpendicular to the substrate plane have been studied. The coatings were obtained by the atomic layer deposition (ALD) of aluminum oxide on the structured ITO films. The transmission electron microscopy showed that the deposited nanosized aluminum oxide layer was of good quality and uniformly covered the ITO whiskers. As shown in experiments, the thickness of the resulting Al2O3 layer is affected by the thickness and, hence, by the degree of surface roughness of the initial ITO film. The resulting thicknesses can be several times lower than that planned in the experiment, based both on the calculations of the parameters of the ALD process and on the direct measurements of the aluminum oxide deposition rate for unstructured ITO films. A possible reason that affects the growth rate of A1O3 layers in nanostructured ITO films is a strong increase in the surface area of the ITO film during its structuring. So, the transmission and scanning microscopy data for a 700 nm-thick structured ITO film have shown that its surface area is more than 20 times greater than that of a smooth film. [ABSTRACT FROM AUTHOR]

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The basic physical properties and applications of semiconductor quantum dots have attracted the attention of researchers. The properties of quantum dots mainly depend on the size and density, and the density, height and other parameters of quantum dots control the nucleation of adatoms on the substrate. In this paper, metal In droplets are grown on GaAs( 001) surface by droplet epitaxy. The relationships of the diffusion movement of In droplets with substrate temperature and deposition rate are studied. It is found that with the increase of substrate temperature and the decrease of deposition rate, the size of in droplets increases, but the density decreases. Through the experimental data obtained, the curves of In droplet density with substrate temperature and deposition rate are fitted, the growth mechanism of quantum ring is analyzed, and the mechanism of surface atomic diffusion is further analyzed. [ABSTRACT FROM AUTHOR]

Electroless plating of Ni--B alloy was conducted on the surface of iron specimen. The effects of the dosage of nickel salt, reducing agent, and complexing agent in the bath, and different stabilizers on the deposition rate, appearance, and microhardness of Ni--B alloy coating were studied. The bath composition was optimized as follows: SF-815 nickel salt A 60 mL/L, SF-815 complexing agent B 200 mL/L, SF-815 reducing agent C 20 mL/L, and thiol-containing compound as stabilizer 5 mg/L. The Ni--B alloy coating obtained by electroless plating from it at pH 6.2-7.2 and temperature 60-70 °C for 1 hour was uniform, semi-bright, fine-grained, and compact with a mass fraction of B ranging from 1.62% to 3.23% and a microhardness of 683.0-753.1 HV. The bath was stable as be shown by keeping clear after being used continuously for 10 turnovers, as well as the appearance and other properties of the coating remained qualified. [ABSTRACT FROM AUTHOR]

• A multi-field coupling model is based on COMSOL5.6 simulation platform and finite element method is applied to numerical simulation. • The effects of process parameters on coating polysilicon thin films are studied concurrently. • A new wafers placement strategy is proposed to achieve further improvements in deposition rate and uniformity. The high photoelectric conversion efficiency of tunnel oxide passivating contacts (TOPCon) photovoltaic (PV) cells and their process compatibility are increasingly recognized by the industry, making it of growing importance to develop deposition process technologies for high-capacity polysilicon thin films. Currently, the size of LPCVD reactors for preparing polysilicon thin films in the industry is getting enlarged, which directly leads to the degradation of axial uniformity of polysilicon thin films. In this paper, a coupled multi-physics field model is established to simulate the polysilicon thin-film Low Pressure Chemical Vapor Deposition (LPCVD) process based on COMSOL Multiphysics platform, and the validity of the model is verified by comparing experimental data with simulation results. By investigating the flow field, thermal field, chemical reaction field and surface reaction field, the effects of the process parameters such as chamber temperature and pressure are investigated, as well as characteristics of the polysilicon thin films deposition. The results show that the uniformity of thin films decreases with increasing temperature and pressure, and the deposition rate of thin films increases as temperature and pressure increase. With the help of optimized the process parameters, the deposition rate of polysilicon thin films was increased by 13.0% and the uniformity of thin films was controlled above 96%. The uniformity of the films can be further improved to 96.7% by optimizing the temperature zone parameters and adopting the wafers placement strategy. [ABSTRACT FROM AUTHOR]

Electroless Ni–P coatings are successfully deposited on the surface of pre-phosphorized zirconium alloy from plating baths containing various concentrations of rare earth oxide (Re Y2O3, Ce2O3 and La2O3). The surface morphology, elementary composition, and structure of coatings are characterized by scanning electron microscopy, energy dispersive X-ray spectrometer and X-ray diffraction, respectively. Gravimetrical method is used to calculate the deposition rate. Electrochemical corrosion resistance of coatings is analyzed using electrochemical workstation. Results revealed that a small amount addition of rare earth oxides does not change the original cauliflower-like morphology and amorphous structure of coatings. When the amount of addition is moderate, the deposition rate and microhardness increase with the increment of the amount of addition, while P content decreases. However, excessive addition can lead to poisoning of the plating bath. Electrochemical corrosion data indicates that the addition of rare earth oxide in the plating solution has little influence on the corrosion resistance of the coating. [ABSTRACT FROM AUTHOR]

In parabolic trough technology, the development of thermally and structurally stable solar coatings plays a key role in determining the efficiency, durability, and economic feasibility of tube receivers. A cermet-based solar coating is typically constituted by a thin film stratification, where a multilayer graded cermet is placed between an infrared metallic reflector and an antireflection filter. This work reports the realization of materials based on Al2O3 and W characterized by high structural and chemical stability in vacuum at high temperature, obtained through the optimization of high-deposition-rate processes. Al2O3 material, employed as the antireflection layer, was deposited through a reactive magnetron sputtering process at a high deposition rate. Cermet materials based on W-Al2O3 were deposited and employed as absorber layers by implementing reactive magnetron co-sputtering processes. An investigation into the stability of the realized samples was carried out by means of several material characterization methods before and after the annealing process in vacuum (1 × 10−3 Pa) at high temperature (620 °C). The structural properties of the samples were evaluated using Raman spectroscopy and XRD measurements, revealing a negligible presence of oxides that can compromise the structural stability. Spectrophotometric analysis showed little variations between the deposited and annealed samples, clearly indicating the high structural stability. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Antimonene has attracted much attention due to its excellent characteristics of high carrier mobility, thermoelectric properties and high stability. It has great application prospects in Q-switched lasers, laser protection and spintronics. At present, the epitaxy growth of antimonene mainly depends on molecular beam epitaxy. We have successfully prepared antimonene films on silicon, germanium/silicon substrates for the first time using electron beam evaporation coating and studied the effects of the deposition rate and substrate on the preparation of antimonene; film characterization was performed via confocal microprobe Raman spectroscopy, via X-ray diffraction and using a scanning electron microscope. Raman spectroscopy showed that different deposition rates can lead to the formation of different structures of antimonene, such as α phase and β phase. At the same time, it was found that the growth of antimonene is also affected by different substrates and ion beams.

In the pursuit of refining the fabrication of three-dimensional (3D) microelectrode arrays (MEAs), this study investigates the application of ultrasonic vibrations in template-assisted electrodeposition. This was driven by the need to overcome limitations in the deposition rate and the height uniformity of microstructures developed using conventional electrodeposition methods, particularly in the field of in vitro electrophysiological investigations. This study employs a template-assisted electrodeposition approach coupled with ultrasonic vibrations to enhance the deposition process. The method involves utilizing a polymeric hard mask to define the shape of electrodeposited microstructures (i.e., micro-pillars). The results show that the integration of ultrasonic vibrations significantly increases the deposition rate by up to 5 times and substantially improves the uniformity in 3D MEAs. The key conclusion drawn is that ultrasonic-enhanced template-assisted electrodeposition emerges as a powerful technique and enables the development of 3D MEAs at a higher rate and with a superior uniformity. This advancement holds promising implications for the precision of selective electrodeposition applications and signifies a significant stride in developing micro- and nanofabrication methodologies for biomedical applications.

This study aims to determine the effects of deposition time on the phase and structure of FeCoNi. FeCoNi was prepared by electrodeposition method at room temperature. X-ray diffraction measurement shows the formation of a single phase of FeCoNi at 5 and 10 minutes of deposition, while at 20, 35, and 50 minutes, a new phase was formed, namely CoNi. The obtained FeCoNi and CoNi show a crystal plane at 2θ = 44.05° (111); 51.33° (002); and 75.59° (022) in all different deposition times, indicating the face centered cubic crystal structure. The effect of deposition time on the chemicals composition shows an anomalous co-deposition because Fe has a larger ratio than Co and Ni. The deposition rate and the value of current efficiency were found to be optimum at FeCoNi synthesized for 20 minutes, namely 0.00214 mg/cm2s and 97.00%.