Academic literature on the topic 'THERMAL SPRAY OF COATING'

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Journal articles on the topic "THERMAL SPRAY OF COATING"

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Jeandin, Michel, Dimitris Christoulis, Francois Borit, Marie Helene Berger, S. Guetta, G. Rolland, Vincent Guipont, et al. "Lasers and Thermal Spray." Materials Science Forum 638-642 (January 2010): 174–81. http://dx.doi.org/10.4028/www.scientific.net/msf.638-642.174.

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Basically, thermal spray and laser processing can be considered as half brothers since they show many common features due to the use of a (more or less) high-energy source for both. Their combination can therefore be very fruitful and prominent to achieve coatings, which results in their most recent and advanced applications. In the materials processing development story, the laser will thus have moved from cutting to coating. This keynote presentation focuses on the recently-developed coupling of laser processing to cold spray). In this dual process, a cold spray gun is combined to a laser head in a single device, e.g. on a robot. Series of coating experiments using various laser irradiation conditions, primarily pulse frequency, were carried out for Al-based and Ni-based alloys. Laser pre-treatment of the substrate just prior to cold spray, was shown to be beneficial for adhesion of cold-sprayed coatings. Adhesion improvement was exhibited and studied from LASATesting (LASAT for “LAser Shock Adhesion Test”). Incidentally, through LASAT also, the role of lasers in the development of thermally-sprayed coatings can be considered as major. Results are discussed in the light of a TEM (Transmission Electron Microscope) study of the coating-substrate interface with and without laser pre-treatment.
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Raza, Ali, Faiz Ahmad, Thar M. Badri, M. R. Raza, and Khurshid Malik. "An Influence of Oxygen Flow Rate and Spray Distance on the Porosity of HVOF Coating and Its Effects on Corrosion—A Review." Materials 15, no. 18 (September 12, 2022): 6329. http://dx.doi.org/10.3390/ma15186329.

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Thermal spray coating, exceptionally high-velocity oxyfuel (HVOF), improves the corrosion resistance and wear of metal. Coating parameters play a vital role in the properties of the coating. The quality of coating can be increased by selecting appropriate coating parameters. In the case of HVOF, the oxygen flow rate and spray distance are the most significant parameters that directly influence the porosity and corrosion resistance of the coating. Porosity is essential in thermal barrier coatings for low thermal conductivity, but there is a limit of porosity beyond which it can cause failure. Hence, understanding the effects of these parameters is essential to evaluate and further minimize the porosity in order to improve the corrosion resistance and durability of the thermal barrier coating. This article reviews hot corrosion in thermal barrier coatings, the stages of corrosion, the importance of spray parameters, and the effect of the oxygen flow rate and spray distance on the corrosion resistance of HVOF-sprayed coatings. Afterwards, the coating materials, the substrate, the flow rate of oxygen, the spray distance, and the fuel used during the HVOF spraying process from recent articles are summarized. In summary, this review compares the flow rate of oxygen and the spray distance with the corrosion capacity of the coating under different corrosive environments and materials to optimize these parameters for high-quality coating, which would sustain under high temperatures for future applications.
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Ni, Weiliang, Peng Li, Yajun Zhu, Zhigang Di, Liangliang Guo, and Yunqi Liu. "Comparative Study of Anti-Corrosion Properties and Lifespan Prediction Model for Inorganic Zinc-Rich Coating and Thermal-Spray Zinc Coating." Coatings 12, no. 4 (April 8, 2022): 505. http://dx.doi.org/10.3390/coatings12040505.

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On the basis of guaranteeing the reliability of the coating, thermal-spray zinc coating has been verified by the industry to have a lifespan of more than 20 years. It is an anti-corrosion coating with excellent performance. Inorganic zinc-rich coating being a new coating technology has a certain degree of influence on its popularization and application in the field of anti-corrosion; this is due to the lack of relevant comparison data on its anti-corrosion performance and service life. It is necessary to compare and analyze the service life and corrosion resistance of the two coatings, so as to obtain the best application scenarios for the two coatings and provide a reference for the selection of the most economical coating. Based on coating reliability, 7500 h of accelerated salt-spray tests of inorganic zinc-rich coating and of the thermal-spray coating of steel structures were carried out. Electrochemical and salt-spray tests on inorganic zinc-rich coating and thermal-spray zinc coating were carried out. The micro-corrosion morphology, corrosion rate and corrosion mechanism of the two coatings and the factors affecting the corrosion rate were obtained. An interfacial corrosion-thinning and weight-loss equation was established to predict the service life of inorganic zinc-rich coating by comparing it with that of the thermal-spray zinc coating salt-spray test; they suggested that inorganic zinc-rich coating has a longer service life. The results are of practical guiding significance for the selection of a zinc coating and the rapid selection and design of a supporting scheme, and can also provide a reference for the service-life prediction of other types of coatings.
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Gao, Lihua, Fang Jia, and Xiaoliang Lu. "Preparation and Thermal Shock Resistance of Gd2O3 Doped La2Ce2O7 Thermal Barrier Coatings." Coatings 11, no. 10 (September 29, 2021): 1186. http://dx.doi.org/10.3390/coatings11101186.

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As one of the promising thermal barrier coating (TBC) candidates, stoichiometric (La0.8Gd0.2)2Ce2O7 (LGC) coatings were prepared by atmospheric plasma spraying (APS), using (La0.8Gd0.2)2Ce2.5O8 as a spray powder and optimized spray parameters. It was found that spray distance and spray power both play an important role in the phase composition and microstructure of the coating. The LGC coating exhibited lower thermal conductivities than that of La2Ce2O7 (LC) coating, which is ~0.67 W/m·K at 1200 °C. Double-ceramic-layer (DCL) optimum (La0.8Gd0.2)2Ce2O7/YSZ (LGC/YSZ) thermal barrier coating was prepared and its thermal shock behavior was investigated. The LGC/YSZ DCL TBCs had better thermal shock resistance ability than that of LC/YSZ TBCs, which was around 109 cycles at 1100 °C. However, the failure mode was similar to that of LC/YSZ DCL TBCs, which was still layer-by-layer spallation in the top ceramic layer due to the sintering of the ceramic coating.
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Wielage, Bernhard, Thomas Lampke, and Thomas Grund. "Thermal Spraying of Wear and Corrosion Resistant Surfaces." Key Engineering Materials 384 (June 2008): 75–98. http://dx.doi.org/10.4028/www.scientific.net/kem.384.75.

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Thermal spraying is one of the most variable and diverse surface coating techniques concerning materials to be processed as well as possible geometries to be coated. The group of thermal spray processes covers a large parameter field to combine nearly each coating with each base material. Thermally sprayed coatings can be applied very evenly and therefore allow to be applied on final-shaped components. Otherwise, if further treatment or finishing is necessary, thermal spray coatings can be processed by grinding or even milling. Masking during the coating process permits the selective coating of specific surface parts or the application of required geometrically structures, e. q. conductor structures. The main application field of thermal spray coatings is the (combined) wear and corrosion protection of selected component parts.
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Dinh, Văn Chien, Tuan Hai Nguyen, and Khac Linh Nguyen. "Studying Adhesion between a 67Ni18Cr5Si4B Alloy Powder Coating Produced with the High Velocity Oxygen Fuel Thermal Spray Method HVOF and a Substrate Surface of a Worn C45 Steel Shaft." Key Engineering Materials 854 (July 2020): 117–25. http://dx.doi.org/10.4028/www.scientific.net/kem.854.117.

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Nowadays, thermal spray coatings are used to enhance mechanical properties of the material. One of the technologies used to produce thermal spray coating is HVOF spray technology. This is the most advanced and modern technology which has been widely used in the industry due to its flexibility and ability to create coatings with better adhesion in comparison with other thermal spray methods. This article presents some empirical findings from applying the 67Ni18Cr5Si4B alloy powder coating onto C 45 steel shaft by HVOF spray technology. It also analyzes the influence of some technological parameters on the adhesion of the coating. As a result, the parameters of HVOF spray technology are obtained suitable for recovering worn axis-sized workpieces.
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Naidu, S. V., Carlos Green, Christopher Maxie, James D. Garber, and Gary A. Glass. "Surface Analysis of Shear Strength Tested Tungsten Carbide Thermal Spray Coatings+." Microscopy and Microanalysis 3, S2 (August 1997): 791–92. http://dx.doi.org/10.1017/s1431927600010849.

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Thermal spray processing has become an important powder-consolidation technique to yield new materials for extremes of temperature, radiation, wear, corrosion and mechanical stresses. High Velocity Oxy-Fuel (HVOF) spray coating process gives higher deposition densities and coating hardness; lower oxide content and porosity. The adhesive strength of thermal spray coatings is greatly effected by the interfacial impurities. The ring shear test method shown in Fig. 1 appears to give the most accurate results on shear adhesive strength. A typical ring shear test result of 88WC12Co 1/4" ring HVOF thermal spray coating on 4140 steel rod using a Jet kote thermal spray gun is shown in Fig. 2. Repeated ring shear tests on similar samples prepared under same spray and test conditions resulted in different shear bond strength and coating ring displacement before break off. We examined the ring shear tested coatings using a Zeiss DMS942 Scanning Electron Microscope (SEM) and Kevex Energy Dispersive X-ray Spectrometer (EDXS) with LPX1 Quantum Si(Li) Detector.
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Yang, Mu Ye, Kazuyoshi Muto, Shigenobu Kainuma, Jin Xuan Du, and Hirokazu Miyata. "Deterioration Characteristics of Overlapping Layers between Al-5Mg Thermal Spray Coating and Heavy-Duty Paint Coating." Materials Science Forum 972 (October 2019): 235–40. http://dx.doi.org/10.4028/www.scientific.net/msf.972.235.

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In recent years, Al-5Mg alloy thermal spray coatings have been used as an anti-corrosion coating applied for various components of steel structures, in some cases it was covered by the conventional heavy-duty coating. However, the deterioration characteristics of overlapping layers between thermal spray layer and heavy-duty paint coating still not clear. In this study, to compare the anti-corrosion characteristics of the single thermal spray coating and overlapping layers, the accelerated cyclic exposure tests were carried out on specimens with three types of coating layers. To clarify the deterioration characteristics, the cross-cut defect were introduced into specimens, and the EIS measurements, glossiness test, EPMA elemental analyses were conducted on test specimens. The test results indicated that the deterioration of the overlapping layer at the steel base-exposed portion occurs earlier than the case of Al-5Mg thermal spray coating. In addition, the deterioration of thermal spray coating was accelerated by the sealing treatment in specimen with overlapping layers.
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Krishna, L. Rama, D. Sen, Y. Srinivasa Rao, G. V. Narasimha Rao, and G. Sundararajan. "Thermal spray coating of aluminum nitride utilizing the detonation spray technique." Journal of Materials Research 17, no. 10 (October 2002): 2514–23. http://dx.doi.org/10.1557/jmr.2002.0366.

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The main objective of this work is to examine the feasibility of depositing aluminum nitride (AlN) powders, synthesized using self-propagating high-temperature synthesis, on a mild steel substrate using the detonation spray coating technique. Thick coatings produced by utilizing the AlN powder were obtained at four different oxygen–acetylene ratios and analyzed for microstructure, microhardness, porosity, indentation fracture toughness, and phase distribution. The AlN powder particles were found to be undergoing oxidation during the deposition process. The interrelationship between the spray parameters and the extent of oxidation of AlN during the coating process was investigated. Tribological performance of the coatings was evaluated using a dry sand abrasion test and a pin-on-disc sliding wear test. The mechanical and tribological properties of the above four coatings were compared with pure alumina (Al2O3) coatings. The correlation between the structure of the coatings and their tribological performance was also established.
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Faisal, N. H., R. Ahmed, A. K. Prathuru, A. Paradowska, and T. L. Lee. "Measuring Residual Strain and Stress in Thermal Spray Coatings Using Neutron Diffractometers." Experimental Mechanics 62, no. 3 (November 10, 2021): 369–92. http://dx.doi.org/10.1007/s11340-021-00803-9.

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Abstract Background During thermal spray coating, residual strain is formed within the coating and substrates due to thermo-mechanical processes and microstructural phase changes. Objective This paper provides a comprehensive guide to researchers planning to use neutron diffraction technique for thermal spray coatings, and reviews some of these studies. Methods ENGIN-X at the ISIS spallation source is a neutron diffractometer (time-of-flight) dedicated to materials science and engineering with high resolution testing. The focus is on the procedure of using ENGIN-X diffractometer for thermal spray coatings with a view that it can potentially be translated to other diffractometers. Results Number of studies involving neutron diffraction analysis in thermal spray coatings remain limited, partly due to limited number of such strain measurement facilities globally, and partly due to difficulty is applying neutron diffraction analysis to measure residual strain in the thermal spray coating microstructure. Conclusions This technique can provide a non-destructive through-thickness residual strain analysis in thermally sprayed components with a level of detail not normally achievable by other techniques. Neutron sources have been used to measure strains in thermal spray coatings, and here, we present examples where such coatings have been characterised at various neutron sources worldwide, to study residual strains and microstructures. Graphic Abstract
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Dissertations / Theses on the topic "THERMAL SPRAY OF COATING"

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Greving, Daniel James. "Residual stresses and thermal spray coating performance /." Access abstract and link to full text, 1995. http://0-wwwlib.umi.com.library.utulsa.edu/dissertations/fullcit/9610608.

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Singh, Virendra. "Rare Earth Oxide Coating with Controlled Chemistry Using Thermal Spray." Doctoral diss., University of Central Florida, 2012. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5503.

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Cerium oxide (Ceria) at nano scale has gained significant attention due to its numerous technological applications. Ceria in both doped and undoped forms are being explored as oxygen sensor, catalysis, protective coating against UV and corrosion, solid oxide fuel cell (SOFC) electrolyte and newly discovered antioxidant for biomedical applications. Therefore, there is an imminent need of a technology which can provide a cost effective, large scale manufacturing of nanoceria and its subsequent consolidation, specially using thermal spray. This dissertation aims to develop a scientific understanding towards the development of pure and doped ceria- based coating for a variety of technological applications, from SOFC applications to corrosion resistant coating. Atmospheric plasma spray (APS) and solution precursor plasma spray (SPPS) techniques for the fabrication of nano ceria coating were investigated. For feedstock powder preparation, a spray drying technique was used for the agglomeration of cerium oxide nano particles to achieve high density coating. Deposition efficiencies and coating porosity as a function of processing parameters were analyzed and optimized using a statistical design of experiment model. The coating deposition efficiency was dependent on the plasma temperature and vaporization pressure of the ceria nanoparticles. However, low standoff distance and high carrier gas flow rate were responsible for the improved density upto 86 [plus or minus] 3%.An alternative novel SPPS technique was studied for a thin film of cerium oxide deposition from various cerium salt precursors in doped and undoped conditions. The SPPS process allows controlling the chemistry of coating at a molecular level. The deposition mechanism by single scan experiments and the effect of various factors on coating microstructure evolution were studied in terms of splats formation. It was found that the precursor salt (nitrate of cerium) with lower thermal decomposition temperatures was suitable for a high density coating. The high concentration and low spray distance significantly improve the splat morphology and reduced porosity (upto 20%). The feasibility of the trivalent cations (Sm 3+ and Gd 3+) doping into cerium oxide lattice in high temperature plasma was discussed and experimentally studied. XRD analysis revealed the nano crystalline characteristic of the coating and lattice expansion due to doping. The extensive transmission electron microscopy, Scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy and thermo gravimetric were conducted to evaluate the precursors, and coating microstructure. Due to facial switching between Ce4+ and Ce3+ oxidation state, the cerium oxide surface becomes catalytically active. Thus, the APS ceria coatings were investigated for their applicability under extreme environmental conditions (high pressure and temperature). The air plasma sprayed coated 17-4PH steel was subjected to high pressure (10 Kpsi) and temperature (300 oF) corrosive environment. The coated steel showed continuous improvement in the corrosion resistance at 3.5 wt% NaCl at ambient temperature for three months study whereas, high pressure did not reveal a significant role in the corrosion process, and however, one needs to do further research. The ceria coated steel also revealed the improvement in corrosion protection (by 4 times) compared to the bare steel at low pH, 300 oF and 4000 Psi environment. This study projects the importance of cerium oxide coatings, their fabrication, optimization and applications.
ID: 031001377; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Adviser: Sudipta Seal.; Title from PDF title page (viewed May 21, 2013).; Thesis (Ph.D.)--University of Central Florida, 2012.; Includes bibliographical references (p. 171-182).
Ph.D.
Doctorate
Materials Science Engineering
Engineering and Computer Science
Materials Science and Engineering
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Ahmed, Rehan. "Rolling contact fatigue of thermal spray coatings." Thesis, Brunel University, 1998. http://bura.brunel.ac.uk/handle/2438/5469.

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The practical advantages of thermal spray coatings like high deposition rates, low cost and tribological properties of high wear resistance have enabled these coatings to become an integral part of aircraft and automobile industry. Recent advancements in thermal spraying techniques like high particle speed and temperature call for new applications for these coatings. This experimental study addresses the Rolling Contact Fatigue performance of thermal spray coatings deposited by a variety of techniques like High Velocity Oxy-Fuel (HVOF), Detonation Gun (D-Gun) and Plasma spraying. RCF tests were conducted using a modified four ball machine in conventional steel ball bearing and hybrid ceramic bearing configurations. Tribological conditions during the RCF tests were varied by changing the test lubricant and the lubrication mechanism, contact load and shape of the drive coated rolling element to vary the roll/slip ratio. RCF tests were analyzed on the basis of the performance, coating failures using surface and subsurface observations, and residual stress studies. Experimental and theoretical studies of the ball kinematics have also been included. These tests revealed that the performance of the coated rolling elements was dependent upon the coating and the substrate properties. The coating thickness, substrate hardness, tribological conditions during the test, coating and substrate material as well as the coating process and the substrate preparation significantly affect the coating performance and the failure modes. Three different failure modes of these coatings have been discussed along with the changes in the near surface residual stress behaviour of the coated rolling elements.
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Kyaw, Si Thu. "Finite element modelling of stresses and failure within plasma spray thermal barrier coating systems." Thesis, University of Nottingham, 2013. http://eprints.nottingham.ac.uk/27952/.

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Air plasma sprayed thermal barrier coating (APS TBC) systems are usually applied to engine components to reduce the temperature of the substrate and increase the efficiency of engines. However, failure of these coatings leads to oxidation and corrosion of the substrate. Therefore, a thorough understanding of the coating failure is necessary to predict the lifetime of coated components. This project has carried out stress analysis and prediction of subsequent failure of APS TBC systems associated with sintering of the TBC, oxidation of the bond coat (BC), substrate geometry, undulations at the coating interfaces and coating fracture toughness. Stress analysis is crucial for predicting TBC failure as stresses in the vicinity of the coating interfaces cause cracks and subsequent coating delamination. The Finite element (FE) method was used for stress analysis of TBC systems at high temperature stage and at cooling stage after operation. Initially, FE model of an axisymmetric unit cell representing the slice of a coated cylinder was used. Different radii for cylinders were used to investigate the significance of substrate curvature on coating stresses. The effect of asperities at the coating interface on residual stresses was observed using 3D models. The models were built based on the actual geometries of asperities, which were extracted from 3D SEM images of the coating interfaces. An Arrhenius approach was utilised to implement changes in mechanical and physical properties of TBC due to sintering. BC oxidation and related changes in its composition were also implemented. The accuracy of assumptions for FE models was validated by comparing the evaluated stresses against experimental results by project partners. Finally, the effects of stresses and fracture toughness of the coatings and coating interfaces on failure of the TBC system were studied, using cohesive surface modelling and extended finite element modelling (XFEM) methods.
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Accardo, Mario G. "Effects of high pressure water jet on aluminum surfaces prior to thermal spray coating." Master's thesis, This resource online, 1995. http://scholar.lib.vt.edu/theses/available/etd-10222009-124845/.

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Vyawahare, Siddharth M. Ahmed Ikram. "Protective thermal spray coatings for polymer matrix composites." Diss., A link to full text of this thesis in SOAR, 2006. http://soar.wichita.edu/dspace/handle/10057/684.

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Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
"December 2006." Title from PDF title page (viewed on Sept. 18, 2007). Thesis adviser: Ikram Ahmed. Includes bibliographic references (leaves 79-81).
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Elhoriny, Mohamed [Verfasser]. "Development of Coupled Offline Robot Trajectory Generation and Coating Simulation for Thermal Spray Processes / Mohamed Elhoriny." Aachen : Shaker, 2017. http://d-nb.info/1159836779/34.

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Tabbara, Hani. "Numerical investigations of thermal spray coating processes : combustion, supersonic flow, droplet injection, and substrate impingement phenomena." Thesis, University of Southampton, 2012. https://eprints.soton.ac.uk/348993/.

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The aim of this thesis is to apply CFD methods to investigate the system characteristics of high speed thermal spray coating processes in order facilitate technological development. Supersonic flow phenomena, combustion, discrete droplet and particle migration with heating, phase change and disintegration, and particle impingement phenomena at the substrate are studied. Each published set of results provide an individual understanding of the underlying physics which control different aspects of thermal spray systems. A wide range of parametric studies have been carried out for HVOF, warm spray, and cold spay systems in order to build a better understanding of process design requirements. These parameters include: nozzle cross-section shape, particle size, processing gas type, nozzle throat diameter, and combustion chamber size. Detailed descriptions of the gas phase characteristics through liquid fuelled HVOF, warm spray, and cold spray systems are built and the interrelations between the gas and powder particle phases are discussed. A further study looks in detail at the disintegration of discrete phase water droplets, providing a new insight to the mechanisms which control droplet disintegration, and serves as a fundamental reference for future developments of liquid feedstock devices. In parallel with these gas-particle-droplet simulations, the impingement of molten and semi-molten powder droplets at the substrate is investigated and the models applied simulate the impingement, spreading and solidification. The results obtained shed light on the break-up phenomena on impact and describe in detail how the solidification process varies with an increasing impact velocity. The results obtained also visually describe the freezing induced break-up phenomenon at the splat periphery.
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Stoica, Virgiliu. "Sliding wear of post-treated thermal spray cermet coatings." Thesis, Heriot-Watt University, 2005. http://hdl.handle.net/10399/220.

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Shin, Dongyun. "Development of High Temperature Erosion Tunnel and Tests of Advanced Thermal Barrier Coatings." University of Cincinnati / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1522415020378523.

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Books on the topic "THERMAL SPRAY OF COATING"

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Thakur, Lalit, and Hitesh Vasudev. Thermal Spray Coatings. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003213185.

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Materials Technology Institute of the Chemical Process Industries (U.S.), ed. Thermal spray coating applications in the chemical process industries. Houston, TX: Published for the Materials Technology Institute of the Chemical Process Industries, Inc. by NACE International, 1993.

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Pawłowski, Lech. The science and engineering of thermal spray coatings. 2nd ed. Chichester, England: Wiley, 2008.

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The science and engineering of thermal spray coatings. Chichester: Wiley, 1995.

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Pawłowski, Lech. The science and engineering of thermal spray coatings. 2nd ed. Chichester, England: Wiley, 2008.

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J, Brogan, and Construction Engineering Research Laboratories (U.S.), eds. Development of recycled polymer blends for thermal spray applications. [Champaign, IL]: US Army Corps of Engineers, Construction Engineering Research Laboratories, 1997.

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L, Houck David, and AMS International. Thermal Spray Division., eds. Thermal spray: Advances in coatings technology : proceedings of the National Thermal Spray Conference, 14-17 September 1987, Orlando, Florida, USA. [Metals Park, Ohio?]: ASM, 1988.

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Bahrami, Arash. Evaluation of thermal spray coatings with peel adhesion test "PAT". Ottawa: National Library of Canada, 2000.

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National Institute of Standards and Technology (U.S.), ed. Thermal spray process reliability: Sensors and diagnostics : summary of a workshop held at National Institute of Standards and Technology. Gaithersburg, MD: U.S. Dept. of Commerce, Technology Administration, National Institute of Standards and Technology, 2001.

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C, Berndt Christopher, Bernecki Thomas F, and ASM International, eds. Thermal spray coatings: Research, design, and applications : proceedings of the 5th National Thermal Spray Conference, June 7-11, 1993, Anaheim, Calif. Materials Park, Ohio: ASM International, 1993.

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Book chapters on the topic "THERMAL SPRAY OF COATING"

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Fauchais, Pierre L., Joachim V. R. Heberlein, and Maher I. Boulos. "Coating Characterizations." In Thermal Spray Fundamentals, 1113–250. Boston, MA: Springer US, 2013. http://dx.doi.org/10.1007/978-0-387-68991-3_15.

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Boulos, Maher I., Pierre L. Fauchais, and Joachim V. R. Heberlein. "Coating Characterizations." In Thermal Spray Fundamentals, 829–906. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70672-2_17.

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Swain, Biswajit, S. S. Mohapatra, and A. Behera. "Plasma Spray Coating." In Thermal Spray Coatings, 317–30. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003213185-13.

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Fauchais, Pierre L., Joachim V. R. Heberlein, and Maher I. Boulos. "Conventional Coating Formation." In Thermal Spray Fundamentals, 807–980. Boston, MA: Springer US, 2013. http://dx.doi.org/10.1007/978-0-387-68991-3_13.

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Boulos, Maher I., Pierre L. Fauchais, and Joachim V. R. Heberlein. "Plasma Transferred Arc Coating." In Thermal Spray Fundamentals, 519–58. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70672-2_12.

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Keshri, Anup Kumar, and Swati Sharma. "Instant Tuning of Wettability of Metallic Coating." In Thermal Spray Coatings, 59–90. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003213185-3.

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Sathishkumar, M., M. Vignesh, V. Sreenivasulu, M. Nageswara Rao, N. Arivazhagan, and M. Manikandan. "Hot Corrosion Characteristics of HVOF-Sprayed Cr3C2-25NiCr Protective Coating on Ni-Based Superalloys." In Thermal Spray Coatings, 209–28. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003213185-8.

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Prasad, C. Durga, Akhil Jerri, and M. R. Ramesh. "Evaluation of Microstructural and Dry Sliding Wear Resistance of Iron-Based SiC-Reinforced Composite Coating by HVOF Process." In Thermal Spray Coatings, 229–41. Boca Raton: CRC Press, 2021. http://dx.doi.org/10.1201/9781003213185-9.

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Ružbarský, Juraj, and Anton Panda. "Roughness of Spray Coating Surface." In Plasma and Thermal Spraying, 85–86. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-46273-8_9.

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Fiedler, Torben, Joachim Rösler, Martin Bäker, Felix Hötte, Christoph von Sethe, Dennis Daub, Matthias Haupt, Oskar J. Haidn, Burkard Esser, and Ali Gülhan. "Mechanical Integrity of Thermal Barrier Coatings: Coating Development and Micromechanics." In Notes on Numerical Fluid Mechanics and Multidisciplinary Design, 295–307. Cham: Springer International Publishing, 2020. http://dx.doi.org/10.1007/978-3-030-53847-7_19.

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Abstract To protect the copper liners of liquid-fuel rocket combustion chambers, a thermal barrier coating can be applied. Previously, a new metallic coating system was developed, consisting of a NiCuCrAl bond-coat and a Rene 80 top-coat, applied with high velocity oxyfuel spray (HVOF). The coatings are tested in laser cycling experiments to develop a detailed failure model, and critical loads for coating failure were defined. In this work, a coating system is designed for a generic engine to demonstrate the benefits of TBCs in rocket engines, and the mechanical loads and possible coating failure are analysed. Finally, the coatings are tested in a hypersonic wind tunnel with surface temperatures of 1350 K and above, where no coating failure was observed. Furthermore, cyclic experiments with a subscale combustion chamber were carried out. With a diffusion heat treatment, no large-scale coating delamination was observed, but the coating cracked vertically due to large cooling-induced stresses. These cracks are inevitable in rocket engines due to the very large thermal-strain differences between hot coating and cooled substrate. It is supposed that the cracks can be tolerated in rocket-engine application.
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Conference papers on the topic "THERMAL SPRAY OF COATING"

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Grimenstein, L. F. "Polymers in Thermal Spray." In ITSC2011, edited by B. R. Marple, A. Agarwal, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima, and A. McDonald. DVS Media GmbH, 2011. http://dx.doi.org/10.31399/asm.cp.itsc2011p0782.

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Abstract Over the year’s polymers have been used in thermal spray coatings. The most known usage is as a polymer used to seal porosity in thermal spray materials. The sealers mostly used do not really work because they do not penetrate very far into the coating. Once the coating is machined or ground the sealer is gone and we have a porosity coating due to fail. One major sealer resin system used, is Phenolic as the resin, that resin is older than most of the audience and loaded with flammable acetone. It also is not a high temperature material nor does it last long since it is a rigid material and does not expand or contract. The old sealers mostly had solvent systems in them and were replaced with a water born polymer. However, our industry has not kept up with the technology of resin based systems. Water systems sound good environmentally but it does not penetrate and really does not work well for this application. Later polyester was used with a ceramic filler to produce an abradable coating for the seal area for turbine applications. More recently higher temperature polymers were used to create a high temperature abradable coating. I want to show you some new polymeric materials that have done some new applications and also recommend additional work for the thermal spray industry for improved applications using the technology of tomorrow.
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Notomi, A., N. Sakakibara, and T. Torigoe. "Recent Application of Thermal Spray to Thermal Power Plants." In ITSC2009, edited by B. R. Marple, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima, and G. Montavon. ASM International, 2009. http://dx.doi.org/10.31399/asm.cp.itsc2009p1106.

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Abstract This paper presents recent developments in thermal spray coating technology for thermal power plants. As for thermal barrier coatings for gas turbines, to accommodate the high gas temperatures required to improve thermal efficiency, a new ceramic topcoat material with low conductivity was developed. As for wear-resistant coatings for boiler parts, a C-Cr-Fe alloy coating was developed that is lower in cost than conventional chromium carbide cermet. Field tests of boiler parts show that the erosion wear rates of these coatings are as good or better than that of conventional cermet.
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Liu, Y., T. Nakamura, V. Srinivasan, A. Gouldstone, and S. Sampath. "Mechanism Underlying Anelastic Properties of Thermal Spray Coating." In ITSC2007, edited by B. R. Marple, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima, and G. Montavon. ASM International, 2007. http://dx.doi.org/10.31399/asm.cp.itsc2007p0225.

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Abstract The microstructure of thermally sprayed ceramic coatings is characterized by the existence of various pores and microcracks. The porous microstructure makes coating desirable for thermal insulation, but this unique microstructural feature also gives rise to anelastic response under tension and compression loads. Detail investigations of curvature measurements of ceramic coated substrate indicate the coatings to exhibit anelastic behavior composed of nonlinear and hysteresis characteristics. In this paper, the mechanisms of such behaviors were studied from curvature-temperature measurements and finite element analysis through modeling the microstructure of yttria stabilized zirconia (YSZ) coating. Computational models contain numerous randomly distributed pores and microcracks with various sizes, aspect ratios, locations and orientations. The effects of such attributes of pores and microcracks on coating anelastic behavior were studied by simulations of curvature change during thermal cycles.
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Irons, G., W. Kratochvil, M. Schroeder, and C. Brock. "Thermal Spray Alternatives for Electroplated Chromium." In ITSC 1996, edited by C. C. Berndt. ASM International, 1996. http://dx.doi.org/10.31399/asm.cp.itsc1996p0039.

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Abstract Many thermal spray coatings provide excellent wear and corrosion resistance, while providing die same surface finish offered by chromium plating. In the past, the choice between thermal spraying or plating was usually based on part size, area to be coated, cost and familiarity with one or the other method. Today, the thermal spray processes are showing greater popularity due to: ♦ New thermal spray processes and coatings with better properties ♦ Increased chromium plating costs due to stricter regulations on the process and the disposal of its waste products ♦ The closing of chromium plating facilities Thermal spraying offers an opportunity to select a coating from a wide variety of processes and materials that will meet the specific requirements of each application. While this may cause some difficulty in selecting the optimum coating, the selected thermal spray coating often has superior propolies and/or lower cost compared to chromium plating. The highest quality coatings are sprayed by the HVOF process, many with carbide containing materials. Dense plasma grayed ceramic materials offer good wear resistance plus elevated temperature capability. The most economical replacements for chromium plate are applied by the two-wire arc spray process. This paper examines the properties and costs of eight different dismal sprayed coatings and compares them with electroplated chromium.
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Puerta, D., F. Anderson, and A. Geary. "The Metallographic Characterization of Thermal Spray Coating Microstructures." In ITSC2008, edited by B. R. Marple, M. M. Hyland, Y. C. Lau, C. J. Li, R. S. Lima, and G. Montavon. Verlag für Schweißen und verwandte Verfahren DVS-Verlag GmbH, 2008. http://dx.doi.org/10.31399/asm.cp.itsc2008p0791.

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Abstract Thermal spray coatings from several different coating families have been metallographically prepared using traditional and modern metallographic techniques. The different recipes used were intended to demonstrate the effect of abrasive on coating appearance. Traditional metallographic recipes, which rely heavily on the use of silicon carbide (SiC) abrasive papers, were found to produce a notably different appearance than those prepared using modern recipes. Modern recipes, which incorporate extended diamond grinding and polishing steps, were found to produce what appears to be a more representative coating structure. Other variables, including mounting media and use of vacuum impregnation, were also found to influence coating appearance.
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Pasandideh-Fard, M., J. Mostaghimi, and S. Chandra. "Numerical Simulation of Thermal Spray Coating Formation." In ITSC 2000, edited by Christopher C. Berndt. ASM International, 2000. http://dx.doi.org/10.31399/asm.cp.itsc2000p0125.

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Abstract A three-dimensional model of free-surface flows with heat transfer, including solidification, was used to model the build-up of a coating layer in a thermal spray process. The impact of several nickel particles on a stainless steel plate in different scenarios was considered. Particles diameter ranged from 40 to 80 µm and their impact velocity ranged from 40 to 80 m/s. Particles were initially super-heated; their temperature ranged from 1600 to 2000°C. Fast growth of solidification was found to be one cause of particle splashing in thermal spray coatings. Different splat morphologies obtained from the numerical model were comparable with those obtained from the experiments. Simulation of the sequential impact of two nickel particles showed side-flow jetting and particle splashing observed in experiments. The numerical model proved to be capable of simulating different impact scenarios that occur in a thermal spray; this was demonstrated by simulating nine consecutive particles during their impact on the substrate. Several characteristics of a coating layer build-up such as particle splashing and formation of small satellite droplets and rings around the splat could be seen in the numerical results. Particle splashing is one possible cause of porosity formation in thermal spray coatings.
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Tan, Y., J. P. Longtin, and S. Sampath. "Modeling Thermal Conductivity of Thermal Spray Coatings: Comparing Predictions to Experiments." In ITSC2006, edited by B. R. Marple, M. M. Hyland, Y. C. Lau, R. S. Lima, and J. Voyer. ASM International, 2006. http://dx.doi.org/10.31399/asm.cp.itsc2006p0341.

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Abstract Thermal conductivity plays a critical role in the thermal transport of thermal sprayed coatings. In this paper, a combined image analysis and finite element method approach is developed to assess thermal conductivity from high-resolution scanning electron microscopy (SEM) images of the coating microstructure. Images are analyzed with a collection of image processing algorithms to reveal the microscopic coating morphology. The processed digital image is used to generate a two-dimensional finite element meshing in which pores, cracks and the bulk coating material are identified. The effective thermal conductivity is then simulated using a commercial finite element code. Results are presented for three coating material systems: yttria stabilized zirconia (YSZ), molybdenum and NiAl, and results are found to be in good agreement with experimental values, obtained using the laser flash method. YSZ coatings are also annealed and the analysis procedure repeated to determine if the technique could accurately assess changes in coating morphology.
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McGrann, R. T. R., J. Kim, J. R. Shadley, E. F. Rybicki, and N. G. Ingesten. "Characterization of Thermal Spray Coatings Used for Dimensional Restoration." In ITSC 2000, edited by Christopher C. Berndt. ASM International, 2000. http://dx.doi.org/10.31399/asm.cp.itsc2000p0341.

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Abstract Thick thermal spray coatings are used to repair worn parts during aircraft overhaul. The thermal spray coating is used to restore a part to its original dimensions. Characteristics of the as-applied coating that affect the performance of thermal sprayed parts are the residual stress in the coating, the tensile bond strength, the amount of porosity, oxides and impurities near the coating/substrate interface, and the hardness of the coating. An understanding of the relation of these coating characteristics to process variables such as the material used for the coating, spray process, spray angle, and thickness of the applied material is needed. In this paper, four thermal spray coatings, Ni5Al, Ni5Al-atomized, (NiCr)6Al, and Inco 718, on a substrate of Hastelloy X are investigated. These materials are applied using two different thermal spray application processes: plasma spray and High Velocity Oxy-Fuel (HVOF). Spray angles of 90° and 45° are used during spraying. The nominal thickness of the applied coatings ranges from 0.4 mm to 1.8 mm. The thermal spray coatings are evaluated in four types of tests. Residual stresses in the coatings and substrate are evaluated using the modified layer removal method. A tensile bond strength test is performed. Metallographic examination is used to determine the porosity and content of oxides and bond zone impurities (percent) of the applied materials. In addition, the hardness of the coating is measured. For the materials and conditions investigated, it is found that residual stress varies with each of the four process parameters. The bond strength for plasma sprayed coatings is related to the type of material and possibly to the coating thickness. The percent porosity varies with coating material, but, for Ni5Al, it does not depend on application process. Oxide content, as a percentage, varies with material and process, but not with spray angle and thickness. The percentage of impurities near the coating/substrate interface varies with process and, for the specimens that were coated using the HVOF process, with thickness. The hardness of the coating was found to vary with material and spray process. For three of the four coatings, hardness increases with thickness but, for Inco 718, hardness decreases as thickness increases.
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Keller, N., G. Bertrand, B. Comas, and C. Coddet. "On the Tailoring of Spray Dried Thermal Spray Powders." In ITSC2001, edited by Christopher C. Berndt, Khiam A. Khor, and Erich F. Lugscheider. ASM International, 2001. http://dx.doi.org/10.31399/asm.cp.itsc2001p0285.

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Abstract In thermal spray, it is well established that tailoring the powder characteristics is of major importance to achieve reproducible coatings on a microstructural and chemical point of view. Among the techniques developed to produce thermal spray powders, spray drying has proved to be the most versatile process. The spray drying method consists in spraying a slurry containing finely dispersed particles of the materials to be agglomerated. However, in order to prepare specific thermal spray powders, two steps have to be mastered: the slurry stability and the spray drying operating conditions. The present study was focused on the relationships that exist between the slurry rheology, the powder morphology and the coating properties. This work was performed on a model material namely Al2O3. In a first part, the effects of the surfactant percentage and pH on the stability of the suspensions were determined. The evolution of the viscosity of the slurries versus the amount of binder was measured. In a second part, these slurries were used to prepare spray-dried powders. The effects of some process parameters such as atomizing air pressure and slurry feed rate on the granule characteristics (morphology, density, particle size distribution, and powder flow ability) were investigated. Finally, some coatings were deposited using the APS technique on steel substrates from the non-sintered spray-dried powder previously realized. The coating morphology and the crystallographic structure were evaluated as a function of the spraying conditions.
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Gross, K. A., F. Y. Yan, C. C. Berndt, and G. P. Simon. "Repair of Multi-Layered, Polymer-Based Thermal Spray Coatings." In ITSC2005, edited by E. Lugscheider. Verlag für Schweißen und verwandte Verfahren DVS-Verlag GmbH, 2005. http://dx.doi.org/10.31399/asm.cp.itsc2005p0074.

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Abstract Polymeric coatings manufactured by thermal spray processes exhibit variable mechanical and adhesion properties that depend on their exact processing schedules. One important advantage of these coatings is that they can be readily repaired by re-spraying any delaminated or otherwise defective regions. In some instances the repaired region exhibits better mechanical attributes than the original coating. In this study the repairability of several classes of polymeric and polymer-ceramic composite coatings were investigated with a focus on the interfacial adhesion properties. The coatings include those of monolayer and bilayer ethylene methacrylic acid (EMAA), and CaCO3-EMAA composites. The coating thickness did not influence the interfacial adhesive strength between the coating and substrate; while a higher preheat temperature produced a greater interfacial cohesion for the monolayer coating on a metal substrate. The substrate preheat temperature played a dominant role concerning the peel strength of the coating. Greater peel strengths were achieved between polymers, at least twofold greater than that between the polymer and the steel substrate when the pre-heat temperature was greater than the melting point of the polymer. The peel strength of the composite coating decreased with filler content; both on the steel substrate and on a previously sprayed polymer coating. On the basis of these observations, the adhesion mechanism between polymers was explained with a model that relied on the formation of welding points.
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Reports on the topic "THERMAL SPRAY OF COATING"

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Biancaniello, Frank S., and Stephen D. Ridder. Thermal spray coatings workshop:. Gaithersburg, MD: National Institute of Standards and Technology, 1998. http://dx.doi.org/10.6028/nist.ir.6460.

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Arnold, Joshua, and Harold Winnie. DTPH56-15-H-CAAP06 Mitigating Pipeline Corrosion using a Smart Thermal Spraying Coating System. Chantilly, Virginia: Pipeline Research Council International, Inc. (PRCI), December 2018. http://dx.doi.org/10.55274/r0011767.

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B.Mi, X. Zhao, and R. Bayles. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality by Eddy Current Method. Office of Scientific and Technical Information (OSTI), May 2006. http://dx.doi.org/10.2172/893900.

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B. Mi, G. Zhao, and R. Bayles. Non-Destructive Evaluation of Thermal Spray Coating Interface Quality By Eddy Current Method. Office of Scientific and Technical Information (OSTI), August 2006. http://dx.doi.org/10.2172/894176.

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Kiser, Matthew T. METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES. Office of Scientific and Technical Information (OSTI), July 2001. http://dx.doi.org/10.2172/786857.

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D. Trent Weaver, Matthew T. Kiser, Frank W. Zok, Carlos G. Levi, and Jeffrey Hawk. METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES. Office of Scientific and Technical Information (OSTI), February 2004. http://dx.doi.org/10.2172/833402.

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Kiser, Matthew T. METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES. Office of Scientific and Technical Information (OSTI), January 2002. http://dx.doi.org/10.2172/793663.

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D. Trent Weaver and Matthew T. Kiser. METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES. Office of Scientific and Technical Information (OSTI), October 2003. http://dx.doi.org/10.2172/822894.

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Matthew T. Kiser. METAL-MATRIX COMPOSITES AND THERMAL SPRAY COATINGS FOR EARTH MOVING MACHINES. Office of Scientific and Technical Information (OSTI), October 2001. http://dx.doi.org/10.2172/828639.

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Kanouff, M. P. Simulation of surface roughness during the formation of thermal spray coatings. Office of Scientific and Technical Information (OSTI), July 1996. http://dx.doi.org/10.2172/412965.

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