bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of Nozzle Expansion Ratio of Circular and Rectangular Cross-Section Nozzle on Velocity and Temperature of Copper Particle with HP Cold Spraying by Computational Fluid Dynamics and Experimental Analysis
Authors: Sakaki Kazuhiko , Iljima Kiyotaka , Tsubata Tomoki 
Published: January 2023

Abstract
This study compares the performance of circular and rectangular cold spray nozzles based on numerical simulations and experimental results. It shows how nozzle geometry and gas pressure affect the velocity and temperature of copper particles at various points in their travel. The goal of the investigation is to establish a nozzle design that achieves a uniform spray pattern with suitable particle impact velocity for the materials and temperatures involved. It was found that a rectangular nozzle with an expansion ratio in the range of 11-12 can provide a more uniform particle velocity with high deposition efficiency at a reasonable gas pressure.
Metal Matrix Composites Using Surface Modified Particles Fabricated by Cold Spray Technique
Authors: Okimura Nana , Ata Nobuhisa , Hirata Yuki , Ohtake Naoto , Akasaka Hiroki 
Published: January 2023

Abstract
This paper describes a process that has been developed for producing thick composite coatings with friction and wear properties that were once only achievable in diamond-like carbon (DLC) films. The process is based on cold spraying and the use of surface modified metallic powders. In this investigation, two such powders were prepared by placing either copper or titanium particles on a negatively biased stainless steel tray and then coating them with a DLC film by pulse plasma chemical vapor deposition. The powders are then cold sprayed onto aluminum plates, creating metal-matrix composite coatings. The thickness of the Cu-DLC composite coating is 250 µm and that of the Ti-DLC coating is 435 µm. In each case, the presence of dispersed DLC in the metal matrix was verified by Raman spectroscopy. Sliding wear tests were also conducted, revealing that the Cu-DLC composite has a lower coefficient of friction than copper film, while the Ti-DLC composite has lower specific wear rate than titanium film.
Microstructural Characteristics of Arc Sprayed CoCr-Based Coatings
Authors: Tillmann W. , Hagen L. 
Published: January 2023

Abstract
Due to their superior wear resistance and oxidation behavior, Stellite coatings are widely used in industrial applications where they are exposed to high temperature. Common processes for applying Stellite coatings include high-velocity oxyfuel spraying, laser cladding, and plasma transferred arc welding. Although Stellite welding consumables are available, there are few studies on arc-sprayed Stellite coatings in the literature. This work investigates the microstructural characteristics of an arc-sprayed deposit produced using a CoCr-based cored wire with 4.5 wt% W. The deposit is examined both in its as-sprayed state and after high-temperature exposure. Microstructure formation is assessed via SEM and EDX analysis, phase transformation processes are determined by XRD analysis, and friction and wear properties are measured. The findings are presented and discussed and compared with those obtained from conventional CoCr-based coatings.
Design the Compositions of Low Friction Coefficient Bimodal Coatings for Heavy Load Component
Authors: Ye Fuxing , Mi Pengbo , Li Changjiu 
Published: January 2023

Abstract
In this study, copper-doped bimodal WC-Co powders are applied to steel substrates by high-velocity oxyfuel spraying and the coatings are evaluated based on their microstructure and high-temperature wear performance. It is shown that the addition of copper reduces coating porosity without affecting the structure of the WC. It also inhibits the decomposition of WC and has a solid diffusion function. The friction coefficients and wear rates determined at different temperatures were found to be consistently low with minimum values being obtained at 450 °C. At high temperatures, the soft copper flows to the surface, forming a self-lubricating film that reduces friction and wear.
Effects of Composition on Mechanical Properties of Suspension Plasma-Sprayed Hydroxyapatite/Titania Coating
Authors: Abir Mirazul Mahmud , Morakul Sarita , Otsuka Yuichi , Miyashita Yukio , Mutoh Yoshiharu 
Published: January 2023

Abstract
In this study, hydroxyapatite, titania, and HA-TiO2 composite layers are deposited by suspension plasma spraying on titanium substrates and assessed by means of SEM and XRD analysis, Raman spectroscopy, and acoustic emission testing. The coatings exhibited dense microstructures with low porosity and good interfacial bond strength. The main phase in the HA and composite coatings was found to be similar to the peak of the feedstock powder. In the composite and titania coatings, besides rutile and anatase, a significant percentage of thermally stable Ti3O5 was observed, which is favorable for photocatalytic performance.
Engineered Thermal Sprayed Oxygen Evolution Electrode for Hydrogen Production by Alkaline Water Electrolysis
Authors: Jiang Tao , Wang Yan , Montavon Ghislain , Liao Hanlin , Liu Taikai , Reissner Regine , Ansar Syed Asif 
Published: January 2023

Abstract
This study shows how HVOF-sprayed NiAl coatings produced using chemical and electrochemical activation processes can serve as oxygen evolution electrodes in alkaline water electrolysis systems. Freestanding hierarchical NiAl structures produced without chemical binders exhibit electrocatalytic performance comparable to state-of-the-art noble catalysts characterized by very low overpotential and high current density without degradation.
CFD Enhanced Thermal Spray Process for Coating of Cylinder Bores of Car Engines
Authors: Schilder Bernd , Garling Andre , Reimer Fabian , Hamann Matthias , Joos Rainer , Hϋger Jens , Pöhlmann Mathias , Lampke Thomas 
Published: January 2023

Abstract
In this paper, the principles of computational fluid dynamics are used to simulate the complex gas flows in the cylinder bore of an automotive engine during internal-diameter twin-wire arc spraying. A number of experiments are conducted as well and the results are presented and analyzed in order to optimize the properties of the coating. The combination of simulation and experiments led to the development of a process that achieves uniform layer adhesion strength over the length of the cylinder bore.
The Mechanisms of Enhancement of Inter-Particle Bonding in In-Situ Micro-Forging Assisted Cold Spray
Authors: Wei Ying-Kang , Luo Xiao-Tao , Li Chang-Jiu 
Published: January 2023

Abstract
In this study, high-strength aluminum alloy AA7055 deposits are prepared using a recently developed cold spray process that employs in-situ microforging. The in-situ hammering effect is achieved by mixing large shot-peening particles into the spray powder and is shown to enhance interparticle bonding along with the plastic deformation of deposited particles. The underlying mechanisms are discussed based on the characterization of interface microstructure and the distribution of oxide film at the interparticle interface.
Feasibility Study of GaN Coatings by Cold Spray Technique
Authors: Zhou Shaoyun , Bernard Chrystelle A. , Ravi Kesavan , Ichikawa Yuji , Ogawa Kazuhiro 
Published: January 2023

Abstract
This study investigates the feasibility of producing GaN coatings on stainless steel, aluminum, and indium tin oxide glass substrates by downstream injection low-pressure cold spraying. The formation of GaN layers on all three materials appears to be due to pseudo deformation of super agglomerated GaN particles. The deposition results showed a saturation limit to coating thickness with the number of passes. Based on XRD spectra of the coating and powder, no phase transformations took place during the spraying process.
Influence of Particle Size and Spray Parameters on Structural, Mechanical, and Electrical Insulation Properties of Alumina Coatings by Atmospheric Plasma Spraying
Authors: Yamane Toshiyuki , Fujimori Kazuya , Kitamura Junya , Wada Tetsuyoshi 
Published: January 2023

Abstract
This study assesses the influence of particle size and spray parameters on the structural, mechanical, and electrical insulation properties of alumina coatings deposited by atmospheric plasma spraying. It has been found that the combination of a relatively fine feedstock powder and high velocity plasma spraying promotes the formation of denser coatings with high dielectric strength. Correlations between dielectric strength and deposition efficiency, coating hardness, crystal structure, and surface roughness are also assessed.
Techno-Economic Assessment of Coating-Based Resistive Heating Systems versus Conventional Heat Tracers
Authors: Rad Milad Rezvani , Ngaokere Kingsley , Kumar Amit , McDonald André , Hayden Daniel 
Published: January 2023

Abstract
The economic feasibility of using thermal-sprayed heat generating coatings for temperature control in steel pipes was investigated. A data-intensive model was developed to compare fabrication, installation, operation, and maintenance expenditures with those of conventional heating cables. The multi-layered coating consists of flame-sprayed Al2O3 and NiCr layers and cold-sprayed copper. Scalability factors were incorporated in the model to estimate the total projected costs for fabricating the coatings as opposed to installing heat tracing. Although material costs for the coating and heat tracing were approximately the same, the cost of fabrication for the coating was higher due mainly to labor expenses. However, the coating-based system was found to be more energy efficient than heat tracing due to the good adhesion and reduced thermal contact resistance between the heating elements and pipe.
Microstructure and Phase Compositions of Silicon Carbide Coatings Prepared by Plasma Spray-Vapor Deposition
Authors: Wang Di , Zhang Shan-Lin , Li Chang-Jiu 
Published: January 2023

Abstract
In this work, silicon carbide coatings were fabricated by plasma spray-vapor deposition in order to study the effect of plasma gas mixtures on coating microstructure and phase composition. Coatings deposited by Ar-H2 plasma gas were found to contain a composite phase of SiC and Si. Moreover, the content of Si increased with increasing H2 content in the gas. The deposition of Si is possibly due to the reaction of C and hydrogen species in the plasma jet, which would explain why pure SiC coatings were obtained when Ar-N2 gas was used.
The Microstructure and Deposition Behavior of NiCr Alloy Coatings Using Laminar Plasma Spraying
Authors: Zhang Hui-Yu , Liu Sen-Hui , Li Cheng-Xin , Yang Guan-Jun , Li Chang-Jiu , Zhang Shan-Lin , Li Lu 
Published: January 2023

Abstract
This study demonstrates a method of plasma spraying in which the plasma is maintained in a laminar (rather than turbulent) state, achieving a much greater jet length with less ambient air engulfment. In the experiments, NiCr coatings were produced at spraying distances between 250 mm and 500 mm, showing that specific structures can be realized by changing stand-off distance. Structures with high porosity, for example, are generated at relatively short distances; dense structures, on the other hand, are obtained at longer stand-off distances that allow feedstock powder to reach a fully melted state. XRD analysis shows that the spraying process does not change the chemical composition of the material, and EDS results indicate that chemical and metallurgical bonding are achieved.
A Novel Numerical and Experimental Investigation Into Radial Injection for Suspension High Velocity Oxy Fuel (SHVOF) Thermal Spray
Authors: Chadha S. , Jefferson-Loveday R. , Hussain T. 
Published: January 2023

Abstract
In suspension high-velocity oxyfuel (SHVOF) thermal spraying, the suspension is usually injected axially into the combustion chamber. Deposition of oxygen sensitive materials such as graphene can be difficult using this approach as the particles degrade with extended exposure to oxygen at high temperatures. Radial injection outside of the nozzle, however, reduces in-flight particle time thereby accommodating oxygen sensitive nanomaterials. The aim of this study is to investigate how radial injection parameters affect in-flight particle conditions during SHVOF spraying. The models used in this work are shown to accurately predict flame temperature in the combustion chamber for an Al3O2 suspension. Experimental observations of the liquid jet obtained using high-speed imaging are compared to numerically predicted values. The results indicate that in-flight particle characteristics can be improved by more than 30% in SHVOF spraying by optimizing the suspension flow rate and radial injection angle.
Deposition of Co3O4 Films as High-Performance Supercapacitor Electrodes Via the Solution Precusor Plasma Spray Route Place
Authors: Yu Zexin , Liu Meimei , Song Chen , Moliere Michel , Liao Hanlin , Ma Yangzhou , Huang Xuanning , Song Guangsheng , Song Chen 
Published: January 2023

Abstract
In this work, binder-free Co3O4 films with in-situ oxygen vacancies are deposited in a one-step process by solution precursor plasma spraying (SPPS). It is believed to the first time Co3O4 layers composed of hexagonal flakes were synthesized through the SPPS route. Specific capacitances up to 1700 F/g were obtained at a scan rate of 5 mV/sec, almost 97% of which was retained after 13,000 cycles at 20 mV/sec. This supercapacitor-like performance is attributed to the synergistic effects of a binder-free composition with in-situ oxygen vacancies and porous nanostructures.
Effect of Hydrogen Admixture on Plasma Jet Characteristics in Low Pressure Spray Processes
Authors: Mauer Georg 
Published: January 2023

Abstract
In plasma spraying, hydrogen is widely used as a secondary working gas. Under low-pressure conditions, even small amounts of hydrogen can have a significant effect on the plasma jet as mechanisms such as diffusion and recombination come into play. This study investigates the influence of Ar-H2 mixtures on electron densities, temperature distributions, and local composition in the plasma jet using optical emission spectroscopy. Several mechanisms reported in the literature are consulted to explain the observed phenomena.
A Novel Strategy for Applying Oxide-Free Self-Fluxing Alloy Coatings by Self-Fusing Atmospheric Plasma Spraying
Authors: Dong Xin-Yuan , Luo Xiao-Tao , Zhang Shan-Lin , Li Chang-Jiu 
Published: January 2023

Abstract
In this study, NiCrBSi powders with a size range of 30-50 μm were deposited on mild steel substrates by self-fusing atmospheric plasma spraying. Particle temperatures exceeded 2400 °C and the deposits were remarkably dense with low oxygen content. Based on the results, a novel strategy is proposed to directly deposit dense, oxide-free coatings by plasma spraying without the need of post-spray fusing processes.
Effect of High-Temperature (550°C) on Tribological Properties of Eco-Friendly Carbon-Based Composite Coating for Piston Ring Application
Authors: Tyagi Ankit , Walia R.S. , Murtaza Qasim 
Published: January 2023

Abstract
The aim of this work is to develop and assess an eco-friendly carbon-based composite coating for piston ring applications. The coatings were produced from sugarcane waste and Mo, NiCr, and CrC powders using high-velocity oxyfuel spraying and thermal chemical vapor deposition. SEM-EDS and XRD analysis confirms the presence of carbides and oxides that cause coating hardness to increase with increasing temperature. At 550 °C, under a 20 N load with a sliding velocity 0.3 m/sec, the friction coefficient of the coating was found to be 0.2, the wear value was 130 μm, and friction force was 4N. The results indicate that the friction and wear properties of the coatings improve with increasing temperature due to the formation of tribo-oxidative films and the effects of graphitization associated with the presence of carbon.
Tailoring Thermal Properties of Plasma Spray Ceramic Coatings for Aluminum Molding
Authors: Levasseur David , Simard Jimmy , Chiesa Franco 
Published: January 2023

Abstract
Coatings applied on steel molds used for casting aluminum parts have two main purposes: avoid mold metal reaction and control thermal transfer to obtain directional solidification. The coatings widely known to foundry operators are water-based sodium-silicate bonded ceramic suspensions; they are air sprayed and cured on mold surfaces and typically last for 100 casting cycles. Although thermal sprayed coatings have been shown to last more than 5000 casting cycles, they are not yet the preferred mold protection method. This study addresses the issue by developing a knowledge base of thermal transfer properties that can be achieved with air plasma sprayed magnesium zirconate powders. The properties are assessed on an instrumented mold using the inverse technique for different coating compositions.
Improvement of Wear Resistance by Thermal Spraying on Surface Layers Prepared by Plasma Transferred Arc Welding on Gray Cast Iron Components
Authors: Oechsner M. , Engler T. , Ellermeier J. , Heider B. , Reisgen U. , Sharma R. , Zokoll E. , González Olivares E. 
Published: January 2023

Abstract
This study evaluates the erosion-corrosion performance of thermal spray hardcoats on bronze-coated gray cast iron. In the experiments, gray cast iron plates are coated with a bronze powder by PTA welding and the coatings are characterized based on microstructure and corrosion and wear testing. The bronze coatings provide good corrosion protection, but are shown to be susceptible to cavitation and erosion wear. To compensate, thermal spray hardcoats, including atmospheric plasma sprayed Al2O3 and Cr2O3 and HVOF sprayed WC-Co, were applied over bronze-coated cast iron and corrosion and wear tests were performed. It is shown that the thermal spray hardcoats greatly improve wear resistance, but despite their interconnected porosities, do not affect the corrosion performance of the underlying bronze.
Cr-Doped Al2O3 Deposited by Solution Precursor Plasma Spraying by Hybrid Water-Stabilized Plasma Torch
Authors: Tesar Tomas , Musalek Radek , Medricky Jan , Cizek Jan , Lukac Frantisek , Csaki Stefan , Chraska Tomas 
Published: January 2023

Abstract
This study investigates the co-deposition of aluminum and chromium oxides from solution precursor feedstocks with the aim of maximizing the α-alumina content. A hybrid water-stabilized plasma torch was used to spray the feedstock materials and the deposition principles were studied. The chemical composition of the deposits corresponded to the formulation of the feedstocks, indicating a uniform deposition of both materials. It was found that α-phase content can be increased in the coatings by increasing the Cr-forming precursor in the solution.
Modeling of Suspension Plasma Spraying Process
Authors: Dalir E. , Mostaghimi J. , Dolatabadi A 
Published: January 2023

Abstract
In this work, numerical models are developed and used to simulate magneto-hydrodynamic fields inside a dc plasma torch during suspension plasma spraying and their influence on arc attachment. A Reynolds stress model is used to simulate turbulent plasma flow and a discrete phase model simulates the effects of arc fluctuation on suspension droplets in the plasma jet. Submicron yttria-stabilized zirconia particles, suspended in ethanol, are modeled as multicomponent droplets and the KHRT model is used to simulate their breakup. The results show that particles are significantly affected by plasma arc fluctuations and that fine particles near the centerline of the torch are hotter and experience better penetration into the plasma jet.
HVOF Spraying MCrAlY Coatings on Single Crystals with Various Sand Blasting Forces
Authors: Lu Xiaoliang , Yuan Kang , Yu Yueguang , Zhang Deming , Liu Jianming 
Published: January 2023

Abstract
Sand blasting and high-velocity thermal spray processes can produce residual stresses in superalloy substrates that can significantly influence microstructure development. To investigate this effect, single-crystal superalloy substrates were sand blasted using different levels of force (zero, light, and heavy) and then coated with a MCrAlY layer by HVOF spraying. Cross-sectional analysis of an as-sprayed sample revealed a subsurface depletion zone with a composition rich in Mo nano precipitates. Cross-sectional examinations after vacuum heat treating and at various points during oxidation testing showed that elemental interdiffusion occurred between the coating and substrate and that sand blasting intensity has a major influence on the depth of the interdiffusion zones.
Anti-Corrosion Performance of the NiCrAlY Coatings Deposited by Two Different Spraying Technologies
Authors: Li Shuqing , Yang Weihua , Ma Guojia , Li Qilian 
Published: January 2023

Abstract
In this study, nickel-base superalloy coatings are deposited on CrMoAl substrates by different spraying methods and the coatings are evaluated based on their microstructure, phase composition, surface and splat morphology, bond strength, and corrosion properties. In the experiments, NiCrAlY powders with a particle size range of 30-45 μm were sprayed by conventional air plasma and a new laser hybrid plasma spraying technique. The spraying parameters are presented along with test results, observations, and conclusions. The coatings produced by laser hybrid plasma spraying had an average porosity of 0.9%, a bonding strength of 117 MPa, and significantly better corrosion properties than the APS layers.
Gas Gun Flyer Plate Impact Testing of Stainless Steel Deposited by Low Pressure Plasma Spraying and Cold Gas Dynamic Spraying
Authors: Jones David R. , Morrow Benjamin M. , Hollis Kendall J. 
Published: January 2023

Abstract
In this study, 316 stainless was deposited by low-pressure plasma spraying under various conditions to obtain different coating structures and by cold gas dynamic spraying for comparison. The coatings were characterized by cross-sectional metallography to assess porosity, oxidation, particle flattening, and elemental composition. The samples were also subjected to flyer plate impact testing in a gas gun to determine their shock propagation and porosity compaction properties. Comparing the results with that of the reference sample shows the effect of deposition conditions on the dynamic behavior of the coatings.
Three-Dimensional Modelling of Cold Spray for Additive Manufacturing
Authors: Garmeh Saeed , Dolatabadi Ali 
Published: January 2023

Abstract
This study employs a three-dimensional simulation to investigate the cold gas dynamic manufacturing process. During the buildup of the desired object, sharp edges, stagnation points, and corners are likely to form that can influence the trajectories of the particles. This leads to dispersion and lack of particle deposition in these areas, which can eventually reduce the precision and efficiency of the build process. A cylindrical and frustum-shaped object are numerically simulated on a substrate to represent typical additively manufactured parts. Particle trajectories and impact conditions with and without these objects are compared. The results provide useful information for understanding the limitations and challenges associated with cold gas dynamic manufacturing, which can help improve the quality and precision of the process.
Effect of Laser Texturing of Substrate Surface on Coating Properties of Cold-Sprayed and Laser-Assisted Cold-Sprayed Aluminum Coatings
Authors: Koivuluoto Heli , Kiilakoski Jarkko , Costil Sophie 
Published: January 2023

Abstract
In this study, aluminum coatings were cold sprayed, with and without laser assistance, on laser-textured aluminum 6060 and Fe52 steel substrates. The results indicate that laser texturing makes for a cleaner coating interface than grit blasting and that the benefits are greatest when spraying on harder substrate materials. For the steel substrate, the optimized topography achieved through laser texturing assisted in particle deformation, leading to the formation of a much tighter coating structure. Laser-assisted cold spraying, in turn, improved deposition efficiency as well as coating density and adhesion. Separately or together, the two processes have proven to be beneficial for cold spraying.