bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transition Mechanism in Flattening of Plasma Sprayed Ceramic Particles
Authors: Fukumoto M. , Maeda N. , Wie B. , Suzuki D. 
Published: April 2023

Abstract
A transition in the flattening behavior of thermally sprayed metals has been observed in previous studies. It has been proposed that ultra-rapid cooled chill structure preferentially formed at the bottom part of the splat may play a role in the generation of disk-shaped metallic splats. The applicability of this hypothesis to other materials was verified experimentally for several ceramic oxides. To accomplish this, Al2O3, Y2O3, and YSZ particles were plasma sprayed onto stainless steel substrates and the fraction of disk-shaped splats was measured as a function of substrate temperature. Splat microstructure was also examined. Unique amorphous and chill structures were observed in the bottom portion of Al2O3 and Y2O3 splats, indicating that similar formation mechanisms may be at work. However, only a columnar microstructure was observed in the YSZ splats, which calls for additional study.
Warm Spraying of High Strength Ni-Al-Bronze for Cavitation Protection
Authors: Krebs S. , Kuroda S. , Katanoda H. , Gaertner F. , Klassen T. , Araki H. , Frede S. 
Published: April 2023

Abstract
Bronze materials such as Ni-Al-bronze show exceptional performance against corrosion, erosive wear, and cavitation erosion due to their high fatigue strength and resistance to plastic deformation, and are thus used for ship propellers and in turbines, pumps, and other equipment where alternating stresses occur. Usually, the respective parts are cast, but in this study, a number of opportunities are evaluated to apply bronze as a coating to critical part surfaces. Initial experiments with cold gas spraying were promising enough to assess the use of warm spraying, a nitrogen-cooled HVOF process that provides similar particle impact velocities but higher particle temperatures, while still minimizing the effects of oxidation. The formation and performance of warm sprayed Ni-Al-bronze coatings was systematically investigated for different combustion pressures and nitrogen flow rates. Substrate preheating was also used to improve coating adhesion. The coatings obtained show low porosities, high strengths, and in some cases, cavitation resistance similar to that of the bulk material.
3D Tomography of Plasma Sprayed Cr-Clad Ni on Alumina
Authors: Wang A. Y. X. , Munroe P. R. , Tran A. T. T. , Hyland M. M. 
Published: April 2023

Abstract
In this work, a mechanically clad NiCr powder feedstock was deposited on alumina substrates by atmospheric plasma arc spraying. The resultant splats were analyzed for features such as interfacial bonding, splat classification and, critically, Cr distribution. Using a slice-and-view sectioning technique in a dual-beam FIB-SEM system, a representative splat exhibiting discrete Ni and Cr regions was physically deconstructed then reconstructed with visualization software to analyze individual layers with the splat. Although the powder feedstock contained Ni particles clad with clusters of Cr, the splats solidified into distinct layers of Ni and Cr with no signs of interaction between them. A model formulated based on this observation shows that the distribution of Cr cladding on the Ni particulates influences the amount and location of Cr around the solidified Ni splats.
Microstructure and Thermal Conductivity of Fe-Based Amorphous Coatings Prepared by HVOF Thermal Spraying
Authors: Wang L. , Zhou Z. , Yao H. H. , Wang Y. M. , Wu X. , He D. Y. 
Published: April 2023

Abstract
In this work, gas-atomized FeCr powders were deposited on aluminum substrates by HVOF spraying, forming dispersion strengthened coatings with a dense layered structure and low porosity. SEM, TEM, and XRD analyses show that the coatings primarily consist of amorphous matrix (40%) with precipitated nanocrystals and hard boride phases. A number of coating properties, including microhardness, bonding strength, and thermal conductivity, were measured and are correlated with spraying conditions.
Optimization to Fabrication Method of Al-Ni Composite for Shaped Charge Liner Applications
Authors: Lee S. , Park H. , Kim J. , Lee C. , Kim S. J. , Lee S. 
Published: April 2023

Abstract
In this study, arrested reactive milling (ARM) is used to prepare Al-Ni composite powder for deposition on copper liners via kinetic spraying. Among the main goals are to obtain a better understanding of how the milling process affects deposition efficiency and the reactivity of the coatings and to find a way to reduce the amount of remaining solid lubricant after milling. Al-Ni powders were produced under a wide range of conditions and heated to various temperatures to eliminate stearic acid. The powders were sprayed using fixed process parameters and deposition efficiencies, reactivities, and heat values were measured and are compared along with coating microstructures. The procedures used are described and the findings of the study are presented and discussed.
Fractal Analysis of Wear Debris for Plasma Sprayed MoS2/Ni-SiC-Y Solid Self-Lubricant Coatings
Authors: Yuan X. , Zha B. , Jiang L. , Yu Z. 
Published: April 2023

Abstract
This study assesses the effect of yttrium additions on plasma sprayed MoS2/Ni-SiC-Y coatings produced from particle-reinforced composite powders. It is shown that the microstructure of the self-lubricating coatings improves with the addition of yttrium, resulting in increased hardness and cohesive strength. The tribological properties of the coatings were also studied, showing that the ideal amount of yttrium is 12 wt% based on wear loss measurements and that the fractal dimension of sliding wear debris depends on the friction load as well as the mass fraction of yttrium.
A New Type of High-Performance Thermal Spray Powder with WB Reinforcement
Authors: Xie Y. , Xie L. , Wang H. , Yang Y. , Hou C. , Liu B. , Song X. 
Published: April 2023

Abstract
This study assesses the microstructure and mechanical properties of tungsten boride (WB) powder and cemented carbide coatings with WB additions. HVOF-sprayed layers produced from 60WC-30WB-10Co composite powders are compared with conventional 88WC-22Co and 86WC-10Co-4Cr coatings based on phase composition, hardness, wear resistance, and wear surface structure. The results indicate that Co reacts with WB during spraying, forming ternary phases (WCoB, W2CoB2) that increase hardness as well as sliding wear resistance.
Hot Corrosion Behavior of Multi-Layer Suspension Plasma Sprayed Gd2Zr2O7/YSZ Thermal Barrier Coatings
Authors: Jonnalagadda K. P. , Mahade S. , Curry N. , Li X.-H. , Markocsan N. , Nylén P. , Björklund S. , Peng R. L. 
Published: April 2023

Abstract
This study investigates the corrosion resistance Gd2Zr2O7/YSZ coatings and a YSZ layer of similar thickness. All coatings were produced by suspension plasma spraying, resulting in a columnar structure. Corrosion tests conducted at 900 °C for 8 h in a molten salt bath show that Gd2Zr2O7 is not as corrosion resistant as YSZ. Molten salts react with Gd2Zr2O7 producing GdVO4 along the surface as well as between the columns of the coating. The formation of GdVO4 between the columns, in combination with the low fracture toughness of Gd2Zr2O7, is likely responsible for the lower corrosion resistance. Furthermore, the presence of another layer of Gd2Zr2O7 on top of the Gd2Zr2O7/YSZ coating, to prevent salt infiltration, did not improve corrosion resistance.
High Entropy Alloy Coatings for Application as Bond Coating for Thermal Barrier Coating Systems
Authors: Bhattacharya R. , Senkov O. N. , Rai A.K. , Ma X. , Ruggiero P. 
Published: April 2023

Abstract
High-entropy alloys (HEAs) are well suited for use in high-temperature environments due to their combination of strength, ductility, thermal stability, and corrosion and wear resistance. In this study, NiCoCrAlSi-based HEA coatings are deposited by HVOF and air plasma spraying (APS) and their phases, microstructure, and composition are evaluated by means of XRD, SEM, and EDS analysis. The results show that BCC/B2 phases are the main constituent in HVOF coatings that were diffusion heat treated. APS coatings of the same composition, on the other hand, exhibited a two-phase structure consisting of L12 and BCC/B2 phases. The HEA coatings produced by HVOF were tested for oxidation resistance and their morphology and oxide scales were examined with the aim of developing a high-quality bond coat for thermal barrier coating (TBC) systems.
Effect of Content and Type of Reinforcing Particles on the Hardness and Wear Rate of Low-Pressure Cold-Sprayed TiC and B4C-based Metal-Matrix Composite Coatings
Authors: Lee Y. T. R. , Ashrafizadeh H. , Fisher G. , McDonald A. 
Published: April 2023

Abstract
This study evaluates the possibility of depositing hard B4C and TiC reinforcing particles in a Ni matrix using low-pressure cold spraying. It also investigates the effect of particle velocity and kinetic energy on deposition efficiency, microstructure, hardness, and wear resistance. B4C and TiC powders were blended at 50, 75, and 92 wt% carbide content with Ni powder comprising the remainder of the mixture. The impact velocity of sprayed carbide particles was calculated using a mathematical model based on the thermodynamics of compressible fluid flow through a converging-diverging nozzle. The model showed that the kinetic energy of TiC particles prior to impact was three times smaller than that of B4C, resulting in a higher carbide content (18 wt% compared to 8 wt%) due to reduced fracture and rebound of the TiC particles. Although the hardness values of both coatings are within the range of cold-sprayed WC-Co-Ni, wear rates were found to be high.
Tribology and Nanoindentation Study of Suspension HVOF Thermally Sprayed Alumina Coating
Authors: Hussain T. , Shaw E. C. , Pala Z. , Xu F. , Ang A. S. M. 
Published: April 2023

Abstract
In this study, a water-based corundum suspension was used to deposit 60 μm alumina coatings onto carbon steel substrates by HVOF spraying. The aim was to develop thin coatings with superior wear properties. Hydrogen was used as a fuel gas and process parameters were varied to determine their effect on microstructure and properties. Coating microstructure was examined by SEM to assess particle melting and morphology and XRD was used to study the phase transformation of the feedstock suspension. At higher combustion flame energy, the coating transformed primarily to gamma alumina, while at lower energy, it was found to be a mixture of alpha and gamma alumina. Nanoindentation tests were used to measure the hardness and elastic modulus of individual phases. Ball-on-plate wear tests helped reveal the relationship between wear performance and the alpha-gamma ratios in the coatings.
The Main Issues to Address in Modeling Plasma Spray Torch Operation
Authors: Chazelas C. , Vardelle A. , Trelles J. P. 
Published: April 2023

Abstract
Most models used to simulate plasma torch operation consider only the gas domain with the electrodes included as boundary conditions, imposing a current density profile and temperature at the cathode tip. In order to achieve more realistic simulations, it is necessary to include the electrodes and arc column in the calculation domain. This paper discusses some of the issues, factors, and considerations involved in modeling arc-cathode and arc-anode interactions and their effect on the plasma jet. Descriptions of the arc column and plasma jet are based on the coupling of electromagnetic and fluid equations and require thermodynamic, transport, and radiative property values of the gas mixture. In order to capture the stochastic behavior of the arc, it is assumed that the model is 3D and time-dependent.
Fracture Characteristics of High-Velocity Suspension Flame-Sprayed Aluminum Oxide Coatings
Authors: Kiilakoski J. , Lutoschkin A. , Plachetta M. , Apostol M. , Koivuluoto H. , Müller P. , Killinger A. , Vuoristo P. 
Published: April 2023

Abstract
The aim of this work is to evaluate the brittleness of suspension sprayed aluminum oxide coatings with various methods, including Vickers indentation fracture toughness, four-point bending, and high-velocity particle impact testing. Coatings were applied via high-velocity suspension flame spraying (HVSFS) using suspensions of isopropanol and water solvents. HVOF-sprayed Al2O3 powder feedstock was used as a reference. The tests are described and the results are presented and discussed.
Stress Analysis and Failure Mechanisms of Plasma-Sprayed Thermal Barrier Coatings
Authors: Yang J. , Wang L. , Li D. , Zhong X. , Zhao H. , Tao S. 
Published: April 2023

Abstract
Yttria stabilized zirconia coatings were deposited by plasma spraying and heat treated in air at 1100 °C for 50-200 h. Residual stresses in the ceramic topcoat and the thermally grown oxide (TGO) layer were measured before and after thermal exposure. After 50 h of exposure, tensile stress in the as-sprayed topcoat changed to compressive, which then increased with additional exposure time up to 150 h. The average compressive stresses in the cross-section of the TGO layer are shown to be higher than those on the surface of the oxide. In addition to shedding light on the nature and evolution of stresses in plasma-sprayed thermal barrier coating (TBC) systems, the results of the study also provide insights on crack initiation and propagation in the ceramic topcoat and at the topcoat-TGO-bond coat interface and its role in TBC failures.
Characterization of YSZ Coatings Deposited by Conventional dc and CO2-CH4 Torches
Authors: Salimijazi H. R. , Ghasemi R. , Mostaghimi J. , Pershin L. 
Published: April 2023

Abstract
In the present work, hollow sphere YSZ powders were deposited by dc plasma spraying using a mixture of CO2 and CH4 gases. The plasma plume was monitored with an IR camera and in-flight particle velocity and temperature distributions were recorded at impact. Single splats were collected on mirror polished stainless steel and, along with coating samples, were characterized and compared to splats and coatings deposited by conventional argon spraying. In the case of CO2-CH4 spraying, particle temperatures were at least 100 °C higher than the YSZ melting point and almost all splats were completely melted. Coating surfaces were also found to be smoother, indicating less unmelted or partially melted splats.
Microstructure and Properties of FeCrNbBSiC Coating Prepared by Wire-Arc Spraying Process
Authors: Qian Z. H. , Zhou Z. , Yao H. H. , Wu X. , Wang Y. M. , He D.Y. 
Published: April 2023

Abstract
In this study, FeCrNbBSiC coatings are deposited on aluminum alloy 4042 substrates by wire arc spraying and their microstructure, phase composition, hardness, bonding strength, and thermal conductivity are evaluated in comparison with a commercial 316L stainless steel coating. The FeCrNbBSiC samples were found to have a dense and homogeneous lamellar microstructure with much less oxide inclusions than the stainless steel layer. The iron-based coatings were also much harder, mainly due to their composite structure with amorphous and nanocrystalline phases, and their bonding strength was slightly higher. In thermal conductivity testing, the FeCrNbBSiC layers were found to have thermal insulation properties close to that of conventional (YSZ) TBCs, making them a good candidate for engineering use.
Highly Economical Fe-Based Protective Coating System by Novel Material Design and Full Utilization of the Atomized Powder
Authors: Bobzin K. , Zhao L. , Öte M. , Königstein T. 
Published: April 2023

Abstract
In this work, the aim is to develop a cost-effective coating to protect cast iron and carbon steel from corrosion and wear. An alloy with a composition of FeCr25Mn10BC was designed that could be readily converted to powder form by gas atomization. Different sized powders were produced, characterized, and subsequently sprayed using a three-cathode air plasma generator. It was found that fine powders with fractions of -25 +10 μm and -10 μm had a much higher affinity to oxidation than coarser ones. Nevertheless, using suitable parameters, dense coatings with low oxide content could be realized even with the finest powder. The results show that full utilization of the powder is achievable due to the wide parameter window of three-cathode plasma spraying and that the average deposition efficiency is more than 70%. In addition to savings in material and processing costs, the new alloy system provides greater wear resistance than stainless steel coatings and exhibits significantly higher corrosion resistance than unprotected cast iron and carbon steel.
Fe-Based Powder Alloys Deposited by HVOF and HVAF for Sliding Wear Applications
Authors: Dizdar S. 
Published: April 2023

Abstract
This study compares the wear performance of thermally sprayed iron coatings with that of electrolytic hard chrome (EHC) plating. Three Fe-based alloy powders (FeSP529, FeSP586, 6AB) were deposited on S355 structural steel plates by HVOF and HVAF spraying and the resulting coatings and plating samples were subjected to dry sliding wear tests using a block-on-ring setup. Wear maps for all three Fe-based powder alloys are similar, showing regions of plasticity dominated wear, wear transition, and oxidational wear as a function of sliding velocity. More importantly, the wear rates of the sprayed coatings were ten times lower than those of the EHC plating samples.
Nanotopographical Features of Plasma Sprayed Coatings on Bone Implant Surfaces
Authors: Wang G. , Song X. , Zhao X. 
Published: April 2023

Abstract
Previous studies have shown that nanostructured coatings produced by plasma spraying can stimulate cellular activity and promote bone healing. Since then, a number of studies have been conducted to better understand how coating nanotopography can be controlled and how it influences bioactivity and healing. This paper reviews some of the key findings in three areas: the effects of nanotopography on bone cell adhesion, the effects of nanotopography on bone-like apatite formation in simulated body fluid, and how to refine the nanotopography of plasma-sprayed coatings.
Effect of Nitric Acid Corrosion on the Luminescent Intensity of Plasma Sprayed YAG:Ce Coatings
Authors: Zeng P. , Wang H. , Wang W. , Yu J. , Wu L. 
Published: April 2023

Abstract
This study assesses the effect of acid corrosion on the luminescence of YAG:Ce coatings. The feedstock powder is prepared by high-temperature solid phase synthesis and the coatings are deposited by air plasma spraying. Microstructure and phase composition are characterized and the effect of acid immersion duration on luminescent intensity is measured. It is found that the luminescent properties of YAG:Ce3+ coatings have a tendency to fluctuate with immersion time, which appears to be related to phase composition.
Sulfidation Behavior of Plasma-Sprayed Al-Mo Coatings at High Temperature
Authors: Wu L. , Wang W. , Yu J. 
Published: April 2023

Abstract
This work investigates the effects of sulfidation on plasma-sprayed Al-Mo and Mo coatings. Pure Mo powder and Al-Mo powder mixtures were sprayed on Inconel substrates with either a NiCrAlY or Mo bond coat. Oxidation and sulfidation tests were carried out in air and Ar-S2 atmospheres, respectively, at temperatures of 973, 1073, and 1173 K. Coating samples were evaluated before and after testing via SEM and XRD analysis and weight measurements. The results show that Al-Mo coatings with a Mo bond layer provided the best protection against high-temperature oxidation and sulfidation corrosion.
Effect of Substrate Preheating on the Bonding Strength of Detonation Sprayed WC10Co4Cr Coatings
Authors: Gao Y. , Hou Y. , Gao J. 
Published: April 2023

Abstract
This study investigates the influence of substrate preheating on the microstructure, hardness, and adhesion of detonation sprayed WC-CoCr coatings. Using commercially available powders, coating samples are deposited on low carbon steel substrates, some at room temperature and some having been preheated to 300°C. Test results show that the coatings deposited on preheated substrates are harder, more crack resistant, and better adhered, with no significant differences in microstructure. After tensile testing, fracture surfaces and interfaces were investigated, showing how fracture behavior, along with hardness and bonding strength, correlate with phase composition and particle impact conditions.
Impedance Analysis of 7YSZ Thermal Barrier Coatings During High-Temperature Oxidation
Authors: Chen W.-L. , Liu M. , Zhang J.-F. 
Published: April 2023

Abstract
This work evaluates the high-temperature oxidation behavior of thermal barrier coatings by means of impedance spectroscopy. TBCs consisting of YSZ topcoats and NiCoCrAlYTa bond coats were deposited on Ni-based superalloy substrates by atmospheric plasma spraying. Test specimens were heated in air at 1000 °C for different periods of time from 5 h to 250 h. SEM-EDS analysis of the thermally grown oxide (TGO) shows that it mainly contains alumina and grew at a parabolic rate with increasing oxidation time. The resistance of the TGO, as determined by impedance spectroscopy, was found to increase at similar rate. Impedance spectroscopy also revealed an increase in YSZ grain boundary resistance corresponding to grain boundary cracking that occurred in the first 50 h of heating. The YSZ grain boundary resistance remained relatively constant over the interval of 50 to 150 h, but showed a slight decrease beyond 150 h mainly due to sintering effects.
Electrochemical Impedance Spectroscopy of Thermally Sprayed Aluminum in Synthetic Seawater
Authors: Paul S. 
Published: April 2023

Abstract
Commercially pure aluminum was arc sprayed on low-carbon manganese steel and electrochemical impedance spectroscopy (EIS) was carried on coating samples in a simulated marine immersion environment at 35 °C. A simple pore network circuit model was used to analyze the data and calculate the corrosion rate, which was estimated to be 5-15 μm/y from the charge transfer resistance value. After 9 months of exposure, the actual corrosion rate was found to be ~5 μm/y. The mechanism of protection offered by thermally sprayed aluminum (TSA) coatings is discussed.
Microstructure and Wear Resistance of Atmospheric-Plasma-Sprayed AlCoCrFeNiTi High-Entropy Alloy Coating
Authors: Xiong W. , Tian L.-H. , Liu C. , Lu S. 
Published: April 2023

Abstract
In this work, atmospheric plasma spraying was used to deposit an equiatomic AlCoCrFeNiTi high-entropy alloy (HEA) coating with a thickness of 236 μm, a porosity of 1.6%, and an adhesive strength of 50.3 MPa. The as-sprayed coating mainly contained BCC1 and BCC2 phases, with only a trace amount of the FCC phase. Microhardness was four times that of 316 stainless steel and the volume wear rate at room temperature was one-fourth that of the substrate material. The wear rate decreased with increasing temperature from 25°C to 700°C, then increased from 700°C to 900°C. Over that range, the wear mechanism changed from delamination wear to oxidation and adhesion wear.
Influence of the Segmentation Crack on the Stress Distribution and Failure Behavior of the Thick Thermal Barrier Coatings Fabricated by Atmospheric Plasma Spraying: A Numerical Simulation Study
Authors: Wang L. , Yang J. , Li D. , Zhao H. , Zhong X. , Shao F. , Liu C. , Tao S. , Ding C. 
Published: April 2023

Abstract
In this work, finite element modeling is used to investigate the influence of segmentation cracks on stress distribution and failure in thermal barrier coatings deposited by atmospheric plasma spraying. The results indicate that the presence of segmentation cracks does not improve thermal insulation, but it may be beneficial in regard to thermal shock resistance, depending on crack density, and residual stress around crack tips, depending on crack length. It may also improve strain tolerance, which is affected by crack density as well as length. A model is proposed to explain the mechanism of failure in thick TBCs exposed to thermal shock. Damage caused by thermal shock can be attributed to the propagation of segmentation cracks and the formation of horizontal cracks at the bond coat-topcoat interface.