bluuebunny/crossref_metadata_2025_split huggingface dataset:
Wear Resistant Coatings for Radial Shaft Sealing Systems
Authors: Haas W. , Haiser H. , Putzier U. , Putzier J. 
Published: May 2021

Abstract
Due to advanced technical, economic and environmental reasons, radial shaft and hydraulic rod seals demand new wear resistant counterface materials. Thermal spraying offers one alternative to common hardening and hard plating technologies. Applying corrosion resistant ceramic coatings by Thermal Spraying leads to new applications in sealing systems. The combination with PTFE-compound sealing materials can be used with aqueous, non-lubricating and corrosive fluids. The authors have carried out extensive research on how the coating material and the surface structure of the coating effect hydraulic rod and radial shaft sealing systems. The presented results show that the influence of the coating on the sealing is critical for the performance of both standard and new custom sealing systems.
Applications of PTA Powder Welding in Petroleum Chemical Industry
Authors: Huang X. , Wang R. , Xu L. , Luo H. , Yin X. 
Published: May 2021

Abstract
Plasma transferred arc (PTA) welding is widely used in the petroleum and chemical industry to deposit nickel and cobalt-based materials on key parts for the purpose of surface modification. As test results show, the process improves corrosion, wear, and high-temperature resistance, prolonging the service life of components and equipment and reducing production costs.
The Experimental Study on Arc Sprayed Mouldmaking for Plastic Products
Authors: Xu B. , Ma S. , Liu X. , Chen Z. 
Published: May 2021

Abstract
This paper describes some of the problems solved in the development of a mold-making process in which the molds are coated using a 2mm wire arc-spraying system. A water solution release agent has been chosen to meet industry standards and requirements. The composition of backup materials was chosen based on compression strength testing. The material selected has high ultimate compression strength and high thermal conductivity and can be readily incorporated in the mold-making process.
Ca/P Ratio and Biocompatibility of Hydroxyapatite Coatings
Authors: Frayssinet P. , Tourenne F. , Rouquet N. , Primout I. , Mathon D. 
Published: May 2021

Abstract
The decomposition of HA during plasma-spraying can lead to the appearance of calcium oxide (CaO) in the calcium phosphate coatings and an increase of the Ca/P ratio (&gt; 1.67). Rehydration can cause an increase in the pH of the extracellular fluids in close vicinity to the coating and rapid degradation of its thickness. Metal cylinders coated with HA were implanted in rabbit condyles for two months and analyzed by histology to evaluate the effect of the presence of CaO in the coatings during early implantation. Three groups of coatings containing different amounts of CaO: 0.2, 0.5, and 0.9% were implanted. The mean coating thickness was measured on five different sites randomly chosen on each section. The percentage of the coating perimeter in contact with newly farmed bone tissue was also measured. A very small difference in coating thickness was observed between the 0.5% group and the two others. The percentage of coating perimeter in contact with the bone increased with the CaO content. These results show that CaO contamination of the calcium phosphate coating does not impair integration and does not increase degradation during the early stages of implantation.
Development of Fabrication Processes for Tubular Solid Oxide Fuel Cell (SOFC) by Plasma Spraying
Authors: Ju W.T. , Hong S.H. 
Published: May 2021

Abstract
The atmospheric pressure plasma spray processes for functional layers of the tubular solid oxide fuel cell are developed to build a fuel cell structure consisting of air electrode, ceramic electrolyte, and fuel electrode. Further more the characteristics of each film are also investigated. The layers of LSM (La0.65Sr0.35MnO3) air electrode and Ni/8YSZ fuel electrode have porosities of 23 ~32 % sufficient for supplying fuel and oxidant gases efficiently to electrochemical reaction interfaces. The measured electrical conductivities of the electrodes are higher than 90 S/cm at 1000 °C, which satisfy the requirement as the current collecting electrodes. The YSZ electrolyte film has a high ionic conductivity of 0.07 S/cm at 1000 °C, but shows a bit too porous to block the oxygen molecule penetration through it. A unit tubular SOFC is fabricated by the optimized plasma spray processes for depositing each functional film and forming a porous cylindrical supporting tube of the cell, and turns out to have a promising capability of electricity generation.
Combined Metallurgical and Ceramic Coating in the Development of Tubular Ozone Generators
Authors: Gadow R. , Killinger A. , Voss A. , Friedrich C. 
Published: May 2021

Abstract
This paper discusses the development of a metal-coated glass tube that produces ozone more economically than traditional methods. It describes the principle of ozone generation, provides information on ozonizer tubes, and presents the criteria for selecting thermal spray powders. It examines the properties of several multilayer coatings consisting of an oxide ceramic top layer, an Al/Si interlayer, and a borosilicate glass substrate. It was found that the porosity and surface roughness of the oxide layer have a significant impact on the dielectric strength of the composite and the efficiency of the ozone-producing tube.
Ceramic-Clad Ceramic System for Ultrasonic Wave Guidance
Authors: Marple B.R. , Jen C.-K. , Voyer J. 
Published: May 2021

Abstract
Ceramic-clad ceramic components were developed to address the need for buffer rods capable of operating under severe conditions. The buffer rods were produced using plasma spraying to build up a 500-nm thick layer of alumina on a solid alumina rod. Both conventional plasma spraying and high power plasma spraying techniques were employed to deposit the alumina coating directly onto a pre-roughened surface. Characterization of the resulting coatings indicated a level of porosity of several percent, substantially higher than that of the dense core. The room temperature wave propagation characteristics exhibited by these clad buffer rods were significantly improved over that of the unclad components.
Fatigue Behavior of Type 316L Stainless Steel Coated with Plasma-Sprayed Alumina in Corrosive Environment
Authors: Kisuki H. , Sugano M. , Oshima T. , Nasu Y. , Okazaki K. , Nakata K. 
Published: May 2021

Abstract
Fatigue properties of the Al2O3 plasma-sprayed SUS316L stainless steel rod specimens coated on different spraying conditions have been studied in a physiological saline solution (0.9 % NaCl solution) to evaluate the potential of surgical implant application. Fatigue tests were conducted in push-pull loading at the stress ratio of R = -1, and frequency of 2 Hz. Microstructure related with fatigue damage was examined by SEM and TEM. The fatigue strength of Al2O3 plasma-sprayed metals significantly depended on spraying conditions: the effects of spraying on fatigue strength decreased with increasing the applied stress amplitude. As-blasted specimens were higher in fatigue strength than Al2O3 plasma-sprayed specimens. It was found that the plasma spraying had significant effects on fatigue crack growth behavior in the early stage of crack propagation. Fatigue cracks preferentially originated from dents that had been caused on the substrata metal surface subjected to grit-blasting. These results are discussed with both the compressive residual stresses due to the grit blasting which was carried out prior to plasma spraying and the corrosion-resistance of the alumina deposit.
Interface Characterization of Different Apatite Coatings
Authors: Antolotti N. , Bertini S. , Scrivani A. , Fanara C. , Rustichelli F. , Ranz X. , Rey C. 
Published: May 2021

Abstract
The decomposition of bioactive plasma sprayed apatite layers and the weakness of their interface with the metallic substrate limit the longevity of orthopaedic prostheses. Analysis of the coating and of the metal-apatite interface using EDS, XPS, and IR techniques indicates alterations of the apatite composition which can be related to several chemical reactions occurring either in the plasma or on the surface of the implant. EDS shows a calcium-rich layer on the apatite side of the interface whereas after dissolution of the apatite, XPS indicates that phosphorus atoms are incorporated in the metal surface. Depending on the rate of decomposition, calcium oxide may possibly form and weaken the apatite-metal interface. Fluorohydroxyapatite coating have proven to decompose less and differently and to be more effective than hydroxyapatite coatings.
Thermal Spraying Applied onto High Energy Railway Braking: Characterization of Friction Performances
Authors: Bartys H. , Guerin J.D. , Bricout J.P. , Oudin J. 
Published: May 2021

Abstract
Friction materials for braking devices on high-speed trains must be able to dissipate large amounts of energy levels and do so with a minimum amount of mass. Low thermal diffusivity materials such as coated steel discs are of particular interest to researchers in this field. This paper investigates the wear behavior of stellite coatings, based on cobalt or nickel alloys, applied to aluminum titanate pads. The coatings are assessed in terms of friction coefficient, contact temperature, and wear as compared to cermet coated steel discs.
A New Aluminum-Silicon/Boron Nitride Powder for Clearance Control Applications
Authors: Morrell P. , Bettridge D.F. , Greaves M.D. , Dorfman M.R. , Russo L.D. , Britton C. , Harrison K. 
Published: May 2021

Abstract
Abradable coatings are used in gas-turbine engines to optimize compressor performance by maintaining tight blade tip clearances. The most common such coatings are thermally sprayed Al-Si/polyester, Al-Si/graphite, and Ni/graphite. Al-Si/graphite coatings have performed well in terms of wear but are prone to corrosion, which can lead to spalling and a reduction in engine efficiency. In this paper, we chart the development of a powder-based Al-Si/BN abradable material designed to overcome in-service corrosion and analyze laboratory and engine testing results.
Optimisation of Concurrent Fibre Winding and Low Pressure Plasma Spraying for the Manufacture of Titanium Matrix Composite Rings
Authors: Baik K.H. , Grant P.S. 
Published: May 2021

Abstract
A concurrent fibre winding and low pressure plasma spraying (LPPS) process has been developed to manufacture multiple fibre reinforced titanium matrix composite (TMC) rings in a single spraying operation. Optimisation of the LPPS parameters has been successively performed for two different sizes of Ti-6Al-4V powders by experimental design and statistical analysis, which provided minimum porosity and surface roughness for both powders. The most important LPPS parameters affecting porosity and surface roughness of deposits were Ar gas flow rate and chamber pressure. During TMC manufacture, the coarse Ti-6Al-4V powder spraying provided enhanced infiltration between fibres but caused degradation of fibre tensile strength, as well as a rough ring surface. The fine Ti-6Al-4V powder gave no significant degradation of fibre strength and a relatively smooth ring surface. Four-ply SiC fibre reinforced TMCs manufactured by the spray-wind process have also been evaluated in terms of porosity, fibre distribution and fibre damage.
Mechanical and Microstructural Characterisation of a Free Standing Plasma Sprayed Alumina
Authors: Damani R.J. 
Published: May 2021

Abstract
Plasma spraying, commonly used for wear and heat resistant barriers, can be used to produce free-standing bulk ceramic parts as well. In this work the microstructure and phase development of a bulk plasma-sprayed alumina material with about 14 % porosity and splat like grains is investigated in the as-sprayed and various annealed material conditions, using electron microscopic and x-ray diffraction techniques. The fracture characteristics are investigated using standard CT specimens in in-situ SEM experiments. The mechanical response of the material is clearly a result of two features: the pronounced alignment of microstructure itself, and the occurrence of a splat-internal microcrack sub-structure in the as-sprayed condition. This microcrack substructure is a consequence of a splat internal columnar subgrain structure which occurs as a result of the rapid cooling conditions on deposition. The morphology of this subgrain structure and its phase composition is seen to change extensively on annealing. It is found that the mechanical behaviour of the as sprayed material is dominated by this internal subgrain structure, but the behaviour of sufficiently annealed material is dominated by the morphology and mechanical stability of the splat like grains themselves. The biggest change on annealing is not an overall sintering effect, but rather the recrystallisation of the splat internal substructure
Novel ZrO2-Mullite Composites Produced by Plasma Spraying
Authors: Khor K.A. , Li Y. 
Published: May 2021

Abstract
Zirconia can induce enhanced fracture toughness to a number of ceramics when introduced as a reinforcement either in the form of particulates, dispersed phase or whiskers because of its unique tetragonal-monoclinic transformation. This paper presents the preparation of ZrO2 reinforced mullite by plasma spraying a mixture of zircon and alumina. The dissociation of zircon into zirconia and silica in a plasma flame is well-known. Pre-mixed powders of zircon and alumina are injected into a dc plasma jet. The plasma sprayed particles are collected in distilled water and analyzed. The results indicate that the plasma sprayed powders consist of zirconia, zircon and alumina. It was found that fine, mostly amorphous and chemically homogeneous composite powders can be obtained by ball milling and plasma spraying. Recrystallization of amorphous phases and formation of mullite occurred at about 1000 °C in plasma sprayed powders. This value is more than 500 °C lower than the formation of mullite in as-milled powders. Uniform coatings with good structural integrity were obtained by plasma spraying. The amount of amorphous phases was much higher in plasma sprayed coatings than in spheroidized powders, and the relative quantity of mullite in coatings after heat treatment is about 4 times as much as that obtained in the spheroidized powders.
Fabrication of Simulated Nuclear Fuel Pellets by Induction Plasma Deposition
Authors: Gitzhofer F. , Mailhot K. , Boulos M.I. , Jung I.H. , Lee J.S. , Park H.S. 
Published: May 2021

Abstract
A study on induction plasma shape forming with yttria stabilized zirconia (YSZ) was conducted as part of an effort to develop a new method for producing nuclear fuel. YSZ was selected because its melting point is similar to that of UO2. Nuclear fuel pellets were made using a large (70 mm) induction plasma flame that sprays more than 100 pellets simultaneously and a small (10 mm) supersonic plasma flame that produces one pellet at a time. Process optimization for the large induction plasma flame was done based on chamber pressure, plasma plate power, powder spraying distance, sheath gas composition, probe position, and particle size. The best results were 97.11% theoretical density (TD) for 5-mm thick pellets. For the single pellet approach, densities as high as 99% TD have been obtained in 12-mm thick free-standing pellets.
Physico-Chemical Treatment of Zirconia Coatings for Thermal Barriers
Authors: Troczynski T. , Third N. , Pawlowski L. , Covelli L. , Smurov I. 
Published: May 2021

Abstract
This paper explains how laser-beam remelting influences the quality of ceramic coatings on superalloy substrates. The coatings studied consist of Al2O3-Ni ceramic layers. Test results showed that a laser power density of 0.103 x 109 W/m2 is ideal for a beam rate of 1 to 2 m/min. It was also found that coating quality could be further improved by adding a diffusive Cr-Al layer prior to laser remelting. This added step reduces pore volume and layer thickness and increases adhesion without cracks, chips, or spalls. The examination also showed that, depending on cooling rate, it is possible to obtain layers that are similar in composition but different in structure or even amorphic.
Free Form Fabrication of Metallic Components Using the Directed Light Fabrication Process
Authors: Lewis G.K. , Milewski J.O. , Nemec R.B. , Thoma D.B. 
Published: May 2021

Abstract
The Directed Light Fabrication (DLF) process uses a laser beam and metal powder, fed into the laser focal zone, to produce free-standing metal components that are fully dense and have structural properties equivalent to conventional metal forming processes. The motion of the laser focal zone is precisely controlled by a motion path produced from a 3-dimensional solid model of a desired component. The motion path commands move the focal zone of the laser such that all solid areas of the part are deposited and the part can be built (deposited) in its entirety to near net shape, typically within +/-0.13mm. The process is applicable to any metal or intermetallic. Full density and mechanical properties equivalent to conventionally processed material are achieved.
Preparation of Perovskite Powders and Coatings by RF-Suspension Plasma Spraying
Authors: Schiller G. , Muller M. , Gitzhofer F. 
Published: May 2021

Abstract
Perovskite-type LaMnO3 powders and coatings have been prepared by a novel technique, the reactive suspension plasma spraying (SPS) using an inductively coupled plasma of about 40 kW plate power and an oxygen plasma sheath gas. Suitable precursor mixtures were found on the basis of solid state reactions, solubility and the phases obtained during the spray process. Best results were achieved by spraying a suspension of fine MnO2 powder in a saturated ethanol solution of LaCl3 with a 1:1 molar ratio of La and Mn. Low reactor pressure was helpful in order to diminish the amount of corrosive chlorine compounds in the reactor. As-sprayed coatings and collected powders showed perovskite contents of 70-90%. After a post-treatment with an 80% oxygen plasma an almost pure LaMnO3 deposit was achieved in the center of the incident plasma jet.
Latest Gas Turbine Repair Techniques Using Laser Technology
Authors: Williams A.D. , Humphries J.L. 
Published: May 2021

Abstract
Over recent years, with the drive for new higher power, higher efficiency Gas Turbine engines, manufacturers have had to look at new alloys and new coating techniques to achieve and support the industry requirements. Repair technology has therefore had to keep pace with the OEM advances and much research and development has been undertaken in developing new repair processes. Many of the alloys now used are directionally solidified or single crystal, which until now have been deemed irreparable by traditional welding techniques. Recent developments in the use of lasers have not only rendered these alloys salvageable but have also reduced the overall repair time and therefore the cost. This paper looks at the use of laser technology as a repair process for gas turbine components, touching briefly on laser cutting and drilling but concentrating mainly on laser powder feed welding and its applications.
Microplasma Spraying
Authors: Yushchenko K. , Borisov Y. , Pereverzev Y. , Vojnarovitch S. , Darmochval V. , Bobric V. , Ramaekers P. , Raa G. 
Published: May 2021

Abstract
Microplasma spraying unit is characterised by small dimensions, low level of noise and emissions, low power consumption (kW*h/kg). The process provides deposition of coatings on small sized parts and components, including those with fine sections, this being unachievable with any other methods. This makes it possible to widen the scales of the application of plasma spraying and to produce different functional coatings. Microplasma jet has diameter 2-4 mm and length 30-50 mm. Velocities of different powder particles in conditions of microplasma spraying were measured. They amount 15- 60 m/s. Coating from iron-, nickel- and copper alloys were produced. Microstructure and properties of this coatings were studied. A real capability was demonstrated of microplasma spraying of narrow strips of 1-3 mm width with 0.2-0.5 mm thickness on the surface of stainless steel sheets of 0.5 mm thickness and of aluminum alloy of 1 mm thickness, as well as on the surface of 2-6 mm diameter cylindrical samples. The spraying spot has the form of an ellipse elongated along the vertical with 1.1-1.5 axes ratio, depending on the spraying conditions.
Computational Code for Detonation Spraying Process
Authors: Gavrilenko T.P. , Nikolaev Y.A. , Ulianitsky V.Y. , Kim M.C. , Hong J.W. 
Published: May 2021

Abstract
Interactive Computational Code is presented that provides a high-productivity analysis of the complex detonation spraying technology. It is based on exact gas dynamics theory taking into account chemical reactions for description of the gaseous detonation phenomena. It deals with specific features of the process like non-homogeneity of gaseous mixture compositions due to gas filling operation and powder injection into the barrel. Acceleration and heating of powder particles by the detonation product flow were simulated including particle melting, fragmentation and vaporization. Calculations for different fuels and powder materials were accomplished. Optimum conditions (gas mixture, barrel length, powder injection point, etc.) to provide highest velocity and appropriate temperature for typical metal and cermet powders are discussed. The conditions for coating formation by the detonation gun «Ob» were established and samples were produced. Experimental data on detonation coating properties are presented to prove the theoretical results.
Application of Overdriven Gaseous Detonation for Spraying
Authors: Gavrilenko T.P. , Nikolaev Y.A. , Ulianitsky V.Y. 
Published: May 2021

Abstract
The use of overdriven detonation waves can promote coating fabrication from powder materials with high melting temperature and improve the quality coating for all materials. The detonation products flow behind overdriven detonation has kinetic and thermal energy values significantly exceeding those for self-sustaining Chapman-Jouguet's detonation, conventionally used for detonation spraying. This makes it possible to design a micro-gun and, as a consequence, the equipment for internal surface coating.
Thermal Barrier Coatings – Why, How, Where and Where To
Authors: Wigren J. , Pejryd L. 
Published: May 2021

Abstract
Thermal barrier coatings are used in several industries to improve thermal efficiency. Examples are gas turbine engines and marine diesels. The performance and life of thermal barrier coated components depend on a variety of factors all related to the specific application. This paper gives an overview of some of the aspects to consider and put special attention to. The different features, in the microstructure, will be discussed with respect to their appearance and influence on the performance of the TBC. Thermal conductivity, microstructure, failure mechanisms and different applications are highlighted.