共查询到20条相似文献,搜索用时 15 毫秒
1.
Carl Christoph Stahr Sabine Saaro Lutz-Michael Berger Jiri Dubský Karel Neufuss Mathias Herrmann 《Journal of Thermal Spray Technology》2007,16(5-6):822-830
A phase change from α-alumina (corundum) in the feedstock powder to predominantly other alumina phases, such as γ-alumina
in the coating normally takes place, as a result of the spray process. It is expected that the prevention of this phase transformation
will significantly improve the mechanical, electrical, and other properties of thermally sprayed alumina coatings. The results
regarding the possibility of stabilization of α-alumina through addition of chromia published in the literature are ambiguous.
In this work, stabilization using different spray processes (water-stabilized plasma (WSP), gas-stabilized plasma (APS), and
high-velocity oxy-fuel spray (HVOF)) was studied. Mechanical mixtures of alumina and chromia were used, as were prealloyed
powders consisting of solid solutions. The investigations focused on mechanical mixtures with both APS and WSP and on prealloyed
powders with WSP. The coatings were studied by x-ray diffraction, including Rietveld analysis, and analysis of the lattice
parameters. Microstructures were investigated by optical microscopy using metallographic cross-sections. It was shown that
in the case of the mechanically mixed powders, the stabilization predominantly depends on the applied spray process. The stabilization
of the α phase by use of the WSP process starting from mechanical mixtures was confirmed. It appears that stabilization exhibits
a complex dependence on the spray process, the process parameters (in particular the thermal history), the nature of the powder
(mechanically mixed or prealloyed), and the chromia content.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
2.
Chang-Jiu Li Guan-Jun Yang Pei-Hu Gao Jian Ma Yu-Yue Wang Cheng-Xin Li 《Journal of Thermal Spray Technology》2007,16(5-6):1011-1020
Nanostructured WC-Co coating was deposited by cold spraying using a nanostructured WC-12Co powder. The critical velocity for
the particle to deposit was measured. The coating microstructure was characterized by X-ray diffraction analysis, scanning
electron microscopy, and transmission electron microscopy. The coating hardness was tested using a Vickers hardness tester.
The deposition behavior of single WC-Co particle was examined. WC particle size was measured for comparison of deposit properties
to that of sintered bulk. The result shows that the nanostructured WC-Co coating can be successfully deposited by cold spraying
using nanostructured powders. The coating exhibited a dense microstructure with full retention of the original nanostructure
in the powder to the coating. The test of microhardness of the coating yielded a value of over 1820 Hv0.3, which is comparable to that of sintered nanostructured WC-Co. The deposition behavior of WC-Co powders as superhard cermet
materials in cold spraying and powder structure effects is discussed.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
3.
T. Kairet M. Degrez F. Campana J.-P. Janssen 《Journal of Thermal Spray Technology》2007,16(5-6):610-618
Two copper powders were deposited with CGT3000 cold-gas dynamic spray system on aluminum substrates. Mechanical properties
have been studied using microhardness, nanoindentation, and bond strength measurements. The deposition efficiency has also
been studied. The x-ray diffraction patterns allow the characterization of the microstructure such as grain size, strain in
the coating, and dislocation densities. Both powders and coatings have been fully characterized. Three methods have been used
to interpret the x-ray patterns: the Warren-Averbach method, the Hall-Williamson (H-W) method, and the modified H-W method.
A comparison between the state of the powders before and after deposition will give an insight on the metallurgical processes
that take place during the formation of the coating. The influence of the grain size distribution will also be discussed.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
4.
Influence of Annealing on Photocatalytic Performance and Adhesion of Vacuum Cold-Sprayed Nanostructured TiO2 Coating 总被引:1,自引:0,他引:1
Guan-Jun Yang Chang-Jiu Li Sheng-Qiang Fan Yu-Yue Wang Cheng-Xin Li 《Journal of Thermal Spray Technology》2007,16(5-6):873-880
Composite powder was prepared using primary nanoTiO2 powder and polyethylene glycol (PEG). The nanoTiO2 coating was deposited through vacuum cold spray using both the composite powder and the primary nanopowder. The influence
of annealing on the coating adhesion and photocatalytic activity was investigated. The coating adhesion was evaluated through
erosion test by water jet. The photocatalytic performance of the coatings was evaluated through photodegradation of phenol
in water. Results showed that annealing of the coating at a temperature from 450 to 500 °C yielded both higher activity and
better adhesion. The adhesion of the coating deposited using the composite powder was better than that using the primary nanoTiO2 powder. It was found that the TiO2 coating, resulting from the composite powder, presented much higher activity than that deposited with the primary nanopowder.
The better activity is attributed to the existence of large pores resulting from the stacking of composite powder, which benefits
the reactants’ transportation through the porous coating.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
5.
Vasyl Pokhmurskii Hrygorij Nykyforchyn Mykhajlo Student Mykhajlo Klapkiv Hanna Pokhmurska Bernhard Wielage Thomas Grund Andreas Wank 《Journal of Thermal Spray Technology》2007,16(5-6):998-1004
Different posttreatment methods, such as heat treatment, mechanical processing, sealing, etc., are known to be capable to
improve microstructure and exploitation properties of thermal spray coatings. In this work, a plasma electrolytic oxidation
of aluminum coatings obtained by arc spraying on aluminum and carbon steel substrates is carried out. Microstructure and properties
of oxidized layers formed on sprayed coating as well as on bulk material are investigated. Oxidation is performed in electrolyte
containing KOH and liquid glass under different process parameters. It is shown that thick uniform oxidized layers can be
formed on arc-sprayed aluminum coatings as well as on solid material. Distribution of alloying elements and phase composition
of obtained layers are investigated. A significant improvement of wear resistance of treated layers in two types of abrasive
wear conditions is observed.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
6.
Finely structured ceramic coatings can be obtained by solution precursor plasma spraying. The final structure of the coating
highly depends on the droplet size and velocity distribution at the injection, the evolution of the spray in the jet, and
droplet breakup and collision within the spray. This article describes a 3D model to simulate the transport phenomena and
the trajectory and heating of the solution spray in the process. O’Rourke’s droplet collision model is used to take into account
the influence of droplet collision. The influence of droplet breakup is also considered by implementing TAB droplet breakup
models into the plasma jet model. The effects of droplet collisions and breakup on the droplet size, velocity, and temperature
distribution of the solution spray are investigated. The results indicate that droplet breakup and collision play an important
role in determining the final particle size and velocity distributions on the substrate.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
7.
L. C. Erickson T. Troczynski H. M. Hawthorne H. Tai D. Ross 《Journal of Thermal Spray Technology》1999,8(3):421-426
A series of plasma sprayed coatings of controlled microstructure was obtained by spraying three monosize sapphire powders
using an axial injection torch in which the plasma gas composition and nozzle diameter were the only processing parameters
varied. The effects of changes in these parameters on the coating splat morphology, porosity, angular crack distribution,
and hardness are reported. The uniform, dense microstructure and the high hardness of 14 GPa (a level usually only associated
with chromia thermal spray coatings) of the best alumina coatings resulted from using tightly controlled processing conditions
and monodispersed precursor powders. The microstructural quality of plasma sprayed coatings and, hence, the coating properties
can be improved significantly by minimizing variations in processing and raw material parameters.
This paper originally appeared in Thermal Spray: Meeting the Challenges of the 21st Century; Proceedings of the 15th International Thermal Spray Conference, C. Coddet, Ed., ASM International, Materials Park, OH, 1998. This proceedings paper has been extensively reviewed according
to the editorial policy of the Journal of Thermal Spray Technology. 相似文献
8.
Hong-Tao Wang Chang-Jiu Li Guan-Jun Yang Cheng-Xin Li Qiang Zhang Wen-Ya Li 《Journal of Thermal Spray Technology》2007,16(5-6):669-676
It is difficult to deposit dense intermetallic compound coatings by cold spraying directly using the compound feedstock powders
due to their intrinsic low-temperature brittleness. A method to prepare intermetallic compound coatings in-situ employing
cold spraying was developed using a metastable alloy powder assisted with post-heat treatment. In this study, a nanostructured
Fe/Al alloy powder was prepared by ball-milling process. The cold-sprayed Fe/Al alloy coating was evolved in-situ to intermetallic
compound coating through a post-heat treatment. The microstructural evolution of the Fe-40Al powder during mechanical alloying
and the effect of the post-heat treatment on the microstructure of the cold-sprayed Fe(Al) coating were characterized by optical
microscopy, scanning electron microscopy, transmission electron microscopy (TEM), and x-ray diffraction analysis. The results
showed that the milled Fe-40Al powder exhibits lamellar microstructure. The microstructure of the as-sprayed Fe(Al) coating
depends significantly on that of the as-milled powder. The heat-treatment temperature significantly influences the in-situ
evolution of the intermetallic compound. The heat treatment at a temperature of 500 °C results in the complete transformation
of Fe(Al) solid solution to FeAl intermetallic compound.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
9.
Dowon Seo Kazuhiro Ogawa Tetsuo Shoji Shozo Murata 《Journal of Thermal Spray Technology》2007,16(5-6):954-966
The effect of particle size distribution on the degradation behavior of plasma sprayed CoNi- and CoCrAlY coatings during isothermal
oxidation was investigated, in terms of the oxygen content, porosity, surface roughness, and oxide scale formation. The results
show that the degradation of both coatings was considerably influenced by the starting particle size distribution. It also
shows that in the as-sprayed vacuum plasma spray (VPS) coatings the oxygen content on the coating surface increased significantly
with decreased average particle size. But after thermal exposure, the difference of the oxygen contents between the coatings
with different particle size was decreased. The powder with various particle size resulted in low porosity inside the coatings
during the deposition process. The surface roughness of the coatings increased with increased particle size. The small particles
produced a relatively smooth surface, and the oxide growth in the coating deposited by small particle was slower than that
in the large particle coating.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
10.
Thermal spraying is a widely used technology for industrial applications to provide coatings that improve the surface characteristics.
According to the specificities of processes (APS, VPS, flame, electric arc), any kind of material can be sprayed. Among materials,
ceramic coatings present several interesting aspects such as wear resistance, corrosion protection as well as thermal or electrical
insulation; particularly alumina coatings which appear as the most commonly used. From all spraying processes, atmospheric
plasma spraying (APS) is a rather well-established process but some others can also be used with a lower economical impact
such as the flame technology. The aim of this study was to analyze the alumina coating properties according to the technology
employed such as APS or wire flame spraying using the Rokide™ and the Master Jet? guns. After micrographic analyses by SEM, physical and mechanical properties were measured considering the thermal conductivity
and the hardness.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
11.
In previous studies, it has been demonstrated that nanostructured Al2O3-13 wt.%TiO2 coatings deposited via air plasma spray (APS) exhibit higher wear resistance when compared to that of conventional coatings.
This study aimed to verify if high-velocity oxy-fuel (HVOF)-sprayed Al2O3-13 wt.%TiO2 coatings produced using hybrid (nano + submicron) powders could improve even further the already recognized good wear properties
of the APS nanostructured coatings. According to the abrasion test results (ASTM G 64), there was an improvement in wear performance
by a factor of 8 for the HVOF-sprayed hybrid coating as compared to the best performing APS conventional coating. When comparing
both hybrid and conventional HVOF-sprayed coatings, there was an improvement in wear performance by a factor of 4 when using
the hybrid material. The results show a significant antiwear improvement provided by the hybrid material. Scanning electron
microscopy (SEM) at low/high magnifications showed the distinctive microstructure of the HVOF-sprayed hybrid coating, which
helps to explain its excellent wear performance.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
12.
J. Wilden J. P. Bergmann S. Jahn S. Knapp F. van Rodijnen G. Fischer 《Journal of Thermal Spray Technology》2007,16(5-6):759-767
Nowadays, wire-arc spraying of chromium steel has gained an important market share for corrosion and wear protection applications.
However, detailed studies are the basis for further process optimization. In order to optimize the process parameters and
to evaluate the effects of the spray parameters DoE-based experiments had been carried out with high-speed camera shoots.
In this article, the effects of spray current, voltage, and atomizing gas pressure on the particle jet properties, mean particle
velocity and mean particle temperature and plume width on X46Cr13 wire are presented using an online process monitoring device.
Moreover, the properties of the coatings concerning the morphology, composition and phase formation were subject of the investigations
using SEM, EDX, and XRD-analysis. These deep investigations allow a defined verification of the influence of process parameters
on spray plume and coating properties and are the basis for further process optimization.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
13.
This article reports on a series of experiments with various high-velocity oxygen fuel spray systems (Jet Kote, Top Gun, Diamond
Jet (DJ) Standard, DJ 2600 and 2700, JP-5000, Top Gun-K) using different WC-Co and WC-Co-Cr powders. The microstructure and
phase composition of powders and coatings were analyzed by optical and scanning electron microscopy and x-ray diffraction.
Carbon and oxygen content of the coatings were determined to study the decarburization and oxidation of the material during
the spray process. Coatings were also characterized by their hardness, bond strength, abrasive wear, and corrosion resistance.
The results demonstrate that the powders exhibit various degrees of phase transformation during the spray process depending
on type of powder, spray system, and spray parameters. Within a relatively wide range, the extent of phase transformation
has only little effect on coating properties. Therefore, coatings of high hardness and wear resistance can be produced with
all HVOF spray systems when the proper spray powder and process parameters are chosen.
This paper originally appeared in Thermal Spray: Meeting the Challenges of the 21st Century; Proceedings of the 15th International Thermal Spray Conference, C. Coddet, Ed., ASM International, Materials Park, OH, 1998. This proceedings paper has been extensively reviewed according
to the editorial policy of the Journal of Thermal Spray Technology. 相似文献
14.
Effects of Impurity Content on the Sintering Characteristics of Plasma-Sprayed Zirconia 总被引:1,自引:0,他引:1
S. Paul A. Cipitria I.O. Golosnoy L. Xie M.R. Dorfman T.W. Clyne 《Journal of Thermal Spray Technology》2007,16(5-6):798-803
Yttria-stabilized zirconia powders, containing different levels of SiO2 and Al2O3, have been plasma sprayed onto metallic substrates. The coatings were detached from their substrates and a dilatometer was
used to monitor the dimensional changes they exhibited during prolonged heat treatments. It was found that specimens containing
higher levels of silica and alumina exhibited higher rates of linear contraction, in both in-plane and through-thickness directions.
The in-plane stiffness and the through-thickness thermal conductivity were also measured after different heat treatments and
these were found to increase at a greater rate for specimens with higher impurity (silica and alumina) levels. Changes in
the pore architecture during heat treatments were studied using Mercury Intrusion Porosimetry (MIP). Fine scale porosity (<∼50 nm) was found to be sharply reduced even by relatively short heat treatments. This is correlated with improvements in inter-splat
bonding and partial healing of intra-splat microcracks, which are responsible for the observed changes in stiffness and conductivity,
as well as the dimensional changes.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
15.
Sheng-Qiang Fan Chang-Jiu Li Guan-Jun Yang Ling-Zi Zhang Jin-Cheng Gao Ying-Xin Xi 《Journal of Thermal Spray Technology》2007,16(5-6):893-897
Deposition of nanocrystalline TiO2 coating at low temperature is becoming more attractive due to the possibility for continuous roll production of the coating
for assembly lines of dye-sensitized solar cell (DSC) at a low cost. In this study, porous nano-TiO2 coating was deposited by vacuum cold spraying (VCS) at room temperature on a conducting glass substrate using commercial
P25 nanocrystalline TiO2 powder. The microstructure of TiO2 coating was characterized by field emission scanning electron microscopy (FESEM) and nitrogen adsorption test. A commercial
dye (N719) was adsorbed on the surface of TiO2 particles within the coating to assemble a DSC. The cell performance was evaluated by employing simulated solar light at
an intensity of 100 mW/cm2. The results showed that TiO2 coating was deposited by the agglomerates of nano-TiO2 powders. The Brunauer-Emmett-Teller (BET) test of the as-sprayed TiO2 coating yielded a porosity of 49% and an average pore size of 17 nm. The assembled solar cell yielded a short-circuit current
density of 7.3 mA/cm2 and an energy conversion efficiency of 2.4%. The test results indicate that VCS was a promising method to deposit nanocrystalline
TiO2 coatings at low temperature applied to DSCs.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
16.
Yanguang Shan Thomas W. Coyle Javad Mostaghimi 《Journal of Thermal Spray Technology》2007,16(5-6):736-743
Solution precursor plasma spraying has been used to produce finely structured ceramic coatings with nano- and sub-micrometric
features. This process involves the injection of a solution spray of ceramic salts into a DC plasma jet under atmospheric
condition. During the process, the solvent vaporizes as the droplet travel downstream. Solid particles are finally formed
due to the precipitation of the solute, and the particle are heated up and accelerated to the substrate to generate the coating.
This article describes a 3D model to simulate the transport phenomena and the trajectory and heating of the solution spray
in the process. The jet-spray two-way interactions are considered. A simplified model is employed to simulate the evolution
process and the formation of the solid particle from the solution droplet in the plasma jet. The temperature and velocity
fields of the jet are obtained and validated. The particle size, velocity, temperature, and position distribution on the substrate
are predicted.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
17.
Rodolphe Bolot Hanlin Liao Crisalia Mateus Christian Coddet Jean-Michel Bordes 《Journal of Thermal Spray Technology》2007,16(5-6):783-790
This paper presents a CFD (Computational Fluid Dynamic) study and experimental results concerning a rotating twin wire-arc
spray process for the production of coatings on engine cylinder bores. In this process, the wire atomization is performed
using a gas injection coaxially with the cylinder axis. The thermal spray tool is equipped with a deviation head rotating
around the cylinder axis and allowing deflecting the droplet spray perpendicularly to the cylinder surface. The initial deviation
head was found to be not sufficiently efficient so that a new deviation head incorporating an inclined slot was designed and
used. Both CFD results and experiments showed that this new deviation head is more efficient. Moreover, it allowed increasing
the coating bond-strength up to the specifications imposed by PSA Peugeot-Citroen. The present article shows that the wire-arc
spray technology may replace efficiently the Atmospheric Plasma Spray (APS) for the thermal spray of coatings on engine cylinder
bores. Moreover, it shows how CFD may help in solving industrial problems. In particular, the FLUENT CFD code was used in
order to perform improvements of the deviation head design.
This article was originally published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, 2007. 相似文献
18.
Numerical Study of Combination Parameters for Particle Impact Velocity and Temperature in Cold Spray
Numerical simulations of gas/particle flows of cold spray are performed for N2 and He, respectively, to investigate the usefulness of the two material-independent combination parameters derived from the
equations of particle motion and temperature. The first combination parameter is the particle-diameter multiplied by the material
density, which governs the particle velocity. The second one is the squared particle-diameter multiplied by the material density
and specific heat, which affects the particle temperature. In the numerical simulation, the materials of the spray particle
selected are WC-12Co, Cu and Ti. The numerical results show that the maximum impact velocity of particle is obtained, when
the first combination parameter takes specific value regardless of the material type. Furthermore, it is shown that the particle
diameter and its temperature corresponding to the maximum impact velocity can be graphically estimated by using the two combination
parameters for any powder-materials normally used for the thermal spray.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
19.
Corrosion Behavior of Arc Sprayed Nickel-Base Coatings 总被引:1,自引:0,他引:1
In this study, nickel-base cored wires were prepared by using NiCr strip to wrap metal powders of nickel (Ni), chromium (Cr),
molybdenum (Mo), and chromium boron (CrB). Nickel-base coatings were prepared by electric arc spraying. Microstructures of
Ni-Cr-Mo and Ni-Cr-B coatings were investigated using scanning electron microscopy (SEM), energy-dispersive analysis (EDAX),
and x-ray diffraction (XRD) analysis. The coatings have a compact surface and presented a bonding strength higher than 40 MPa.
Potentiodynamic polarization measurements and salt-spray test were carried out to determine the corrosion behavior of the
coatings. The results showed that Ni-base coatings containing Mo (5%) or B (2-4%) had better antichlorine ion corrosion performance
than that of Ni-base coatings without Mo element, and PS45 (Ni-Cr-Ti) coating. The antichlorine ion corrosion coatings could
be used for resolving the corrosion protection problem of the equipment and piping contacting sour, alkali, salt liquid in
petrochemical engineering applications.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献
20.
Effect of Powder Injection Location on Ceramic Coatings Properties When Using Plasma Spray 总被引:1,自引:0,他引:1
The effect of powder injecting location of the plasma spraying on spraying properties was studied. Three different powder-injecting
methods were applied in the experiment. In the first method, the particles were axially injected into the plasma flow from
the cathode tip. In the second method, the particles were radially injected into the plasma flow just downstream of the anode
arc root inside the anode nozzle. In the third method, the particles were radially injected into the plasma jet at the nozzle
exit. The alumina particles with a mean diameter of 20 μm were used to deposit coatings. Spraying properties, such as the
deposition efficiency, the melting rate of the powder particles, and the coating quality were investigated. The results show
that the spraying with axial particle injecting can heat and melt the powder particles more effectively, produce coatings
with better quality, and have higher deposition efficiency.
This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been
expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain
Montavon, Ed., ASM International, Materials Park, OH, 2007. 相似文献