bluuebunny/crossref_metadata_2025_split huggingface dataset:
Performance Comparison of Various Sensor Systems and Plasma Spray Torches
Authors: Gevelber M. , Vattiat B. , Cui C. , Pollard L. , Barker W. , Harter D. , Jelovich J. 
Published: August 2022

Abstract
This study evaluates the performance characteristics of three different torches. A variety of different sensor systems were used to determine how each system resolves the differences in torch spray conditions. Torch performance characteristics include the long term drift behavior in terms of spray pattern and coating profile, the ability to control the particle state, and each torches nonlinear characteristics such as bifurcation (sudden jumps) and on/off repeatability. Sensors include commercially available particle sensors (Tecnar’s DPV 2000, Oseir’s Spraywatch, and Inflight’s IPM), as well as monitoring of plume intensity, acoustic emission, and high frequency voltage/current. Torches include Praxair’s SG 100 (internal injection), Sulzer Metco’s 9MB, and Progressive Technologies 100 HE. The study focused on spraying YSZ under each torches typical operating conditions. Abstract only; no full-text paper available.
Relationship between the Elastic Modulus and Microstructure in Vacuum Plasma Sprayed Structures
Authors: Salimijazi H.R. , Azarmi F. , Coyle T.W. , Mostaghimi J. 
Published: August 2022

Abstract
The structure of thermally sprayed deposit consists of individual lamellae formed from melted and re-solidified particles, along with unmelted and partially melted particles, pores, microcracks, and splat boundaries. The elastic modulus of a vacuum plasma sprayed Ti-6Al-4V alloy parallel to the splat plane determined by standard uniaxial tensile testing was found to be approximately 30% lower than that of conventionally processed materials with the same level of porosity. The relationship between the elastic modulus and the microstructure was studied using an in-situ tensile testing stage in an optical microscope combined with analytical and finite element models. An idealized microstructure was used for the analytical model, which yielded an estimate of the modulus higher than that measured. The finite-element program OOF was also used to compute the elastic modulus based on micrographs of polished and etched surfaces and predicted a reduction of about 37% in the modulus.
Preliminary Study on Plasma Spraying of Ion Conducting Oxides on Bi2O3 Base
Authors: Glazek W. , Pawlowski L. , Vannier R.-N. , Zdanowski J. 
Published: August 2022

Abstract
The powders of Bi2O3 and Bi2WO6 were prepared by calcination, sintering and crushing. Their sizes were screened out to be in the range from 50 to 150 µm. The initial spray parameters were optimised using numerical codes simulating the behaviour of powders in plasma jet. Spray experiments onto metallic substrates were carried out using commercial plasma torch SG-100, equipped in an external powder injector. The spraying of coatings was carried out by varying electric power input to plasma, distance of spraying and the geometry of injector. The morphology of sprayed coatings was investigated using scanning electron microscope (SEM). X-ray Diffraction (XRD) of Bi2O3 coatings revealed the α-Bi2O3 phase, present in the initial powder, and also β-Bi2O3 in some of the samples. Reduction of oxide into metallic Bi at spraying process was not discovered using XRD and Differential Thermal Analysis (DTA). Bi2WO6 powder was crystallized in an orthorhombic phase that transformed into tetragonal one at spraying. Finally, the X-ray Photoelectric Spectroscopy (XPS) investigations revealed a possible presence of Bi(OH)3 phase in the coatings sprayed using Bi2O3 powder.
Effect of Spray Parameters on the Cracking and Spalling Behavior of WC-17% Co Cermet Coatings
Authors: Legoux J.-G. , Bouaricha S. , Sauer J. 
Published: August 2022

Abstract
WC thermal spray based powders are now frequently used as chrome replacement alternatives for a wide range of industrial and aeronautical applications. In numerous cases, the carbide materials outperform the hard chrome in many property evaluations However, its usage on highly stressed parts, especially in fatigue loading, can be limited by spalling resistance of the coating. While HVOF is being used on many flight critical parts, stringent applications like the carrier based landing gear components are still under investigation. This work, on WC-17%Co, relates the processing history of different HVOF processes used at a variety of industrial sources for hard chrome replacement to the coating microstructure and mechanical properties. The thermal history of the WC particles was monitored using a DPV-2000. The mechanical properties of the coatings were assessed following an instrumented four-point bend test as well as uniaxial cyclic loading. The coating microstructures were characterized using X-Ray diffraction and electron microscopy in order to investigate the phase content and nature. In particular, the cracks generated during the bend test were measured using SEM on samples cross sections to measure characteristics such as spacing and crack penetration to the substrate. The goal of the investigation was to better understand the interaction of processing parameters with the cracking/spalling resistance of the varied coating deposits. Abstract only; no full-text paper available.
HVOF Deposition of SOFC Interconnect Materials
Authors: Wang Y. , Garcia E. , Coyle T. 
Published: August 2022

Abstract
One of the tubular cell designs for solid oxide fuel cells is based on a closed-end tube made from the cathode material, with an electrolyte layer coating the outside of the cathode tube, and the anode coating the electrolyte layer. The outer anode layer of one tubular cell is connected to the inner cathode layer of the next tube by the interconnect material. High density is required in the interconnects to prevent mixing of the air and fuel gases. The fabrication of interconnect strips in tubular fuel cell stacks by DC-arc plasma spray deposition has been demonstrated in the past, both in air (APS) and in low pressure (vacuum) conditions (VPS). The High Velocity Oxy Fuel (HVOF) spray deposition technique typically yields among the highest density coatings of all common thermal spray techniques due to the high gas and particle velocities achieved, and therefore would appear to be an excellent method for depositing the interconnects if the powder could be sufficiently melted during spraying. The most common material choice is a doped LaCrO3, a ceramic material with a good thermal expansion coefficient match with the other components of the cell and an acceptable electrical conductivity. The microstructure, phase and chemical composition, and electrical properties of doped LaCrO3 deposited on (La,Sr,Mn)2O3 cathode tubes by HVOF was examined as a function of deposition conditions. Abstract only; no full-text paper available.
Modeling of Combustion Assisted Thermal Spray Processes
Authors: Xia C. , Shamim T. , Mohanty P. 
Published: August 2022

Abstract
The combustion assisted thermal spray systems are being used to apply coatings to prevent surface degradation. They offer a highly attractive way to modify the surface properties of the substrate to extend the product life. The quality of combustion assisted thermal spray coating depends greatly on the flow behavior of reacting gases and particle dynamics. The present study investigates the effect of gas phase and its interaction with particles through the nozzle of a thermal spray gun by developing a comprehensive mathematical model. The objective is to develop a predictive understanding of various design parameters of combustion assisted thermal spray systems. The model was developed by considering the conservation of mass, momentum and energy of reacting gases. The particle dynamics was decoupled from the gas phase dynamics since the particle loading in the spray process is very low. The developed model was employed to investigate the influence of various design parameters on the coating quality of thermal spray process.
Computer Simulation of Injected Particle Behavior During Cold Spray Process
Authors: Kwon E.H. , Han J.W. , Lee C.H. , Kim H.J. 
Published: August 2022

Abstract
The cold spray process is a relatively new process using high velocity metallic particles for surface modifications. Metallic powder particles which are injected into a converging-diverging nozzle are accelerated to supersonic velocities. In this study two-dimensional temperature and velocity distributions of gas along the nozzle axis are calculated and the effects of gas pressure and temperatures on particle velocities and temperatures inside and outside of the nozzle are also investigated. It is found that the acceleration of the gas velocity takes place in the area of the nozzle throat and it increases and reaches maximum value at the nozzle exit. Due to compression shocks in the area after the nozzle, the gas jet properties show irregular shape and these result in the existence of the maximum particle velocity by the change of particle size at a given gas pressure and temperature.
Thermal Properties of Continuously Graded Thermal Barrier Coatings Deposited by Supersonic Plasma Spray
Authors: Wang H. , Xu B. , Han Z. , Zhou S. 
Published: August 2022

Abstract
Continuously graded yttria stabilized ZrO2(YSZ) /NiCoCrAlY coatings were prepared using a high efficiency supersonic plasma-spray system and the thermal shock properties of the coatings were studied. The specimens were so prepared that the two kinds of powders with different melting point were fed to the different regions of the plasma jet by using two powder feeders. The two powders melted perfectly at the same power, and the overheating of the powder with lower melting point was avoided. In this way, a continuously graded transition layer was obtained. The Results show that the continuous change of the coefficients of thermal expansion and thermal conductivity in the transition layer leads to a excellent thermal shock resistance of the totally 0.9mm thick TBCs. The thermal shock cycles of the specimens which underwent heating by oxygen-acetylene flam to 1200 and then quenching into water reached more than 200. The coatings’ surface was still perfect without any visible cracks after the thermal shock test. The analysis shows that the dense structure and the sufficient plastic deformation of the particles depressed the formation of TGOs, which, together with the continuously graded thermal expansion coefficient and thermal conduction coefficient, contributes to the long thermal shock resistance of the coatings.
Relationship between Process Parameters and Microstructure and Wear Characteristics of Plasma Sprayed Nanostructured Al2O3-TiO2 Ceramic Coatings
Authors: Ahn J. , Kim J. , Lee S. 
Published: August 2022

Abstract
The wear characteristics of plasma spray coated layer of Alumina-Titaina composite powder have been investigated, in this study, focusing on the effect of particle size of Alumina powder and parameters of plasma spray coating process. Alumina-Titania composite powders were artificially agglomerated into the size suitable for plasma spray coating process. The process condition for plasma spray coating has been optimized through a statistical data treatment method i.e. response surface analysis. Mechanical properties of coated layer have been measured as a function of the initial Alumina particle size. The structure of Alumina nano-powders in the coated layer was found to be affected by flow rates of Ar and H2 gases, and the power of plasma in a combinational way. The relationship between the wear characteristics of coated layer and process parameters and microstructure of the coated layer was elucidated, by measuring the size distribution, temperature, and velocity of traveling Alumina-Titania composite powder agglomerates. Abstract only; no full-text paper available.
Synthesis and Characterization of Nano-Size La0.8Sr0.2MO3-d Cathode Materials by Induction Plasma
Authors: Gitzhofer F. , Bouchard D. , Sun L. , Brisard G. 
Published: August 2022

Abstract
The synthesis of nanoscale particles has received considerable attention because of the potential for new materials and unique properties. The novel properties and the numerous applications of nanophase materials, especially ceramic nanopowders, have attracted many scientists and engineers to invent and explore the preparation methods of ceramic nanoparticles. Induction plasma is used to synthesize cathode materials for fuel cells. Solid oxide fuel cells (SOFCs) are very promising energy conversion systems. SOFCs are based on an oxide-ion conducting electrolyte and they offer a clean, low-pollution technology to electrochemically generate electricity at high efficiencies. These fuel cells provide many advantages over traditional energy conversion systems including high efficiency, reliability, modularity, fuel adaptability, and very low levels of SOx and NOx emissions. It has been found that La1-xSrxMO3-d, (M= Fe, Co etc) are perovskite materials widely considered as the Intermediate Temperature SOFC cathode materials of choice. In particular, La0.6Sr0.4Co0.2Fe0.8O3-δ is extensively used for IT-SOFCs because its thermal expansion coefficient is relatively close to that of the common electrolytes. In this paper, the nanopowders of SOFC cathode materials were synthesized by thermal plasma spray technique. The results of their structure, morphology and particle size distributions will be presented. Abstract only; no full-text paper available.
A Comprehensive Characterization of Industrially Manufactured Hard Chrome Platings and of Thermally Sprayed Alternatives
Authors: Bolelli G. , Cannillo V. , Lusvarghi L. , Soragni E. , Loreto A. , Valente T. 
Published: August 2022

Abstract
HVOF-sprayed coatings (WC-17Co, WC-10Co-4Cr, Co-28Mo-17Cr-3Si) have been compared with various kinds of industrially manufactured hard chrome coatings (HCC), whose substrate preparation, deposition process, post deposition treatments greatly affect their characteristics. Microstructure, micromechanical properties, tribological behaviour and corrosion resistance (electrochemical polarization tests and Corrodkote test) have been studied. HVOF-sprayed cermets are harder but less tough than HCC, Co-28Mo-17Cr-3Si are less hard than HCC. Splats detachment causes a comparable or higher mass loss in three-body abrasion than HCC coatings. Forming a uniform surface film, cermet coatings definitely overcome HCC in two-body sliding, while Co-28Mo-17Cr-3Si has insufficient hardness to display good sliding wear resistance. HVOF coatings show no passivation in corrosive media but cermets posses more noble corrosion potentials than HCC, and undergo generalized corrosion in HNO3 and HCl, with similar corrosion current densities (IC). HCC passivate and resist well in HNO3 0.1N, but undergo pitting corrosion in 0.1N HCl. Definitely different EC and IC are recorded for various HCC in HCl. HVOF-sprayed cermet coatings show lower IC in 0.1N HCl solution than several kinds of HCC. No visible damage occurs on HVOF-sprayed coatings after the Corrodkote test, while non de-hydrogenated HCC suffered pitting corrosion.
Effect of Surface Oxidation on Transition Temperature of Stainless Steel Substrate Upon Impact of Aluminum Particles
Authors: Pourmousa A. , Abedini A. , Chandra S. , Mostaghimi J. 
Published: August 2022

Abstract
Experimental studies involving aluminum particles sprayed onto polished AISI304L substrates using the Valuarc 200 wire arc previously showed that there exists a transition temperature from splash to disk splats. Increasing the substrate temperature above the transition temperature was seen to increase the number of disc splats, thus producing coatings of improved properties. XPS test results have shown that increasing the substrate temperature also results in increased oxygen content on the surface of the substrate. Experiments also show that prolonged heating of a substrate at a particular (fixed) temperature further promotes oxidation of the substrate surface, thus increasing the surface roughness (Ra). Samples generated on substrates that were held at or above 350°C (above Tt) for prolonged periods of time (over 20 minutes) were seen to promote splashing. This is in contrast to the previous findings that showed substrate temperatures above Tt further promoted disc type splats and improved adhesion between the splat and substrate. Samples generated in this study consistently showed that splashing can be seen at temperature well above the transition temperature, if the substrate has been heated for too long a duration. The cause of splashing is believed to be related to increased surface roughness resulting from prolonged oxidation of the substrate surface. Abstract only; no full-text paper available.
Topological Characterization of Wear Tracks in Thermally Sprayed Abradable Coatings
Authors: Seichepine J.-L. , Albertazzi S. , Nardin P. , Coddet C. , Sporer D. 
Published: August 2022

Abstract
Abradable coatings are located on the stationary parts of gas turbines, in front of blades, which cut a track in them. This has to be achieved with minimum wear of the blades, in order to control the over-tip leakage. These coatings are generally deposited by thermal spraying of composite powders comprising a metal base, a polymer filler generating porosities and a dislocator such as hBN. The very demanding properties are nowadays adjusted using rig tests, where samples are rubbed by the contact of a dummy, simulating actual working conditions in an aircraft engine. Several types of behaviour are usually described, but few numerical data are produced from these tests. Only the blade wear (or metal transfer) is generally measured. As the understanding of contact phenomena is fundamental for the development of predictive models allowing the design of more performing materials, a comprehensive characterization process of the rub path was developed. The study was based on a topological survey made by laser profilometry, giving three-dimensional maps. These maps were then processed by image analysis and several parameters were computed, like surface roughness and parameters giving information on the shape and orientation of the holes or grooves in the rubbed surface of the samples.
Characterization of Nano WC-Co Coatings Produced by Dynamic Powder Deposition
Authors: Kim H.J. , Hwang S.Y. , Lee C.H. 
Published: August 2022

Abstract
WC-Co powders with nano-sized WC were deposited by dynamic powder deposition process. Microstructural characterization and phase analysis of feedstock powders with different compositions and as-deposited coatings with various substrates were carried out by SEM and XRD. The results show that there is no detrimental phase transformation and/or decarburization of WC by dynamic powder deposition. It is also observed that nano-sized WC in the feedstock powder is maintained in the deposited coatings. It is demonstrated that it is possible to fabricate the nano-structured WC-Co coatings with low porosity and very high hardness by dynamic powder deposition.
Study of the Electrical Conductivity of Plasma-Sprayed 4.5mol% Yttria Stabilized Zirconia Coatings
Authors: Ning X.-J. , Li C.-X. , Li C.-J. 
Published: August 2022

Abstract
Y2O3 stabilized ZrO2 (YSZ) coating is widely applied to the electrolyte layer in solid oxide fuel cell. With regard to the application of YSZ coating to solid oxide fuel cell, the electrical conductivity of YSZ coating is of essential importance. In this study, YSZ coating was deposited by plasma spraying using a sinter-crushed powders containing 4.5mol% Y2O3. The electrical conductivity of the coating at both directions parallel and perpendicular to the coating surfaces was measured by a direct current approach. The measurement was carried out at a temperature range from 600 °C to 1000 °C. The effect of spray distance on the electrical conductivity was also examined. The test showed that 4.5YSZ layer yielded the electrical conductivities of 2.2 s·m-1 and 4.3 s·m-1 at a temperature of 1000 °C in both direction perpendicular and parallel to the coating surface, respectively. It is clear that the electrical conductivity of the coating was lower than the identical sintered bulk material. The electrical conductivity of YSZ coatings in this study was of one-fifth to one-fourth in perpendicular direction and about one-half in parallel direction compared with the sintered YSZ bulk. It was considered that the lower electrical conductivity of the coating compared with the identical sintered bulk results from the lamellar structure with the limited interface bonding.
Quality Management System Implementation in LERMPS Laboratory
Authors: Klein D. , Bocci T. , Lahoupe L. , Lamy S. , Coddet C. 
Published: August 2022

Abstract
LERMPS laboratory has been implementing a Quality Management System (QMS) for one year now. Only few Research organisms in the world have begun such process, which has up to now mostly been applied to industrial companies. Hence, the path leading to Quality excellence will be long, but LERMPS is on the way for at least certification, and some interesting results have already been achieved. This QMS implementation is mainly focused for the moment on characterisation team, which are the main support of Thermal Spray and PVD coatings activities in LERMPS. Nevertheless it slightly expands its application area to the whole activity of the laboratory, including administrative support processes. Abstract only; no full-text paper available.