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1.
Hybrid plasma spraying combined with yttrium-aluminum-garnet laser irradiation was studied to obtain optimum zirconia coatings
for thermal barrier use. Zirconia coatings of approximately 150 μm thickness were formed on NiCrAlY bond coated steel substrates
both by means of conventional plasma spraying and hybrid plasma spraying under a variety of conditions. Post-laser irradiation
was also conducted on the plasma as-sprayed coating. The microstructure of each coating was studied and, for some representative
coatings, thermal barrier properties were evaluated by hot erosion and hot oxidation tests. With hybrid spraying, performed
under optimum conditions, it was found that a microstructure with appropriate partial densification and without connected
porosity was formed and that cracks, which are generally produced in the post-laser irradiation treatment, were completely
inhibited. In addition, hybrid spraying formed a smooth coating surface. These microstructural changes resulted in improved
coating properties with regard to hardness, high temperature erosion resistance, and oxidation resistance.
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
2.
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
3.
Shunyan Tao Bo Liang Chuanxian Ding Hanlin Liao Christian Coddet 《Journal of Thermal Spray Technology》2005,14(4):518-523
Reconstituted nanostructured and conventional yttria partially stabilized zirconia coatings were deposited by atmospheric
plasma spray. The tribologic properties of the coatings against 100C6 steel were evaluated with a ball-on-disc configuration
under dry friction conditions at room temperature. Microstructure and the phase composition of the powders and the coatings
were examined using a scanning electron microscope, optical microscope, and x-ray diffraction. Microhardness and the Young’s
modulus of coatings were measured by indentation testing. Results showed that the wear resistance of the coatings produced
using the nanostructured powder is improved compared with the coating produced using the conventional powder. The wear rates
of nanostructured zirconia coatings are about four-fifths of those of conventional counterparts under a load of 5 N. The wear
mechanism is also discussed.
The original version of this paper was published as part of the DVS Proceedings: “Thermal Spray Solutions: Advances in Technology
and Application,” International Thermal Spray Conference, Osaka, Japan, 10–12 May 2004, CD-Rom, DVS-Verlag GmbH, Düsseldorf,
Germany. 相似文献
4.
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
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.
Perovskite-type LaMnO3 powders and coatings have been prepared by a novel technique: reactive suspension plasma spraying (SPS) using an inductively
coupled plasma of approximately 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 to 1 molar ratio of lanthanum and manganese. A low reactor pressure was helpful in diminishing the amount of corrosive
chlorine compounds in the reactor. As-sprayed coatings and collected powders showed perovskite contents of 70 to 90%. After
a posttreatment with an 80% oxygen plasma, an almost pure LaMnO3 deposit was achieved in the center of the incident plasma jet.
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
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.
C. Tekmen K. IwataY. Tsunekawa M. Okumiya 《Journal of Materials Processing Technology》2009,209(14):5417-5422
Graphite formation and degradation in thermally sprayed cast iron coatings is a technological barrier for achieving superior wear resistant coatings. Therefore, there is a need to understand the in-flight particle behavior of cast iron powder and introduce new approaches to control the graphite content. In this study, it has been demonstrated that the graphite content can be controlled by means of in-flight particle diagnostic. For this purpose, cast iron coatings were plasma sprayed under a variety of spray conditions and characterized by using an optical microscope, X-ray diffractometer and electron probe micro-analyzer. As a result, a significant amount of graphite with respect to a wide range of in-flight particle temperature and velocity was preserved in cast iron coatings. 相似文献
9.
在汽车上使用轻质铝合金发动机可以有效减少燃油消耗和环境污染,但铝合金的耐磨损性能较差,从而造成发动机工作过程中气缸壁面容易磨损。利用表面改性技术对铝合金表面进行强化处理,可以满足其作为滑动部件在高载荷条件下的使用要求。灰铸铁较低的成本和其中石墨的自润滑作用,使其成为铝合金发动机气缸表面保护涂层材料的首选。等离子喷涂技术以其高效率和灵活性在表面强化领域受到广泛应用。因此,利用等离子喷涂制备灰铸铁涂层成为改善铝合金发动机气缸表面耐磨性的有效方法之一。但是,由于等离子喷涂过程中熔滴冷却速度极快,等离子喷涂很难得到含大量石墨组织的灰铸铁涂层。以调控灰铸铁涂层中的石墨含量为目的,总结了等离子喷涂灰铸铁涂层的研究现状,以及基体温度、颗粒尺寸、添加合金元素等对熔滴冷却速度的影响,并以此为基础,结合凝固理论分析了在涂层中保留灰铸铁粉末中的石墨组织的可行性,同时分析了在铸铁涂层中保留石墨所面临的主要问题,并提出了解决这些问题的主要措施。最后就在等离子喷涂灰铸铁涂层中保留石墨的研究方向进行了展望。 相似文献
10.
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
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.
等离子喷涂高铬铸铁涂层的摩擦学性能 总被引:1,自引:0,他引:1
针对铝合金缸体内壁油性腐蚀环境中的摩擦工况,采用大气等离子喷涂制得了高铬铸铁涂层和316L不锈钢涂层,采用维氏显微硬度计、图像分析软件、台式扫描电子显微镜及热场发射扫描电子显微镜分别对显微硬度、孔隙率、涂层厚度及结构进行了测试和分析。采用球-盘式往复摩擦试验机对比研究了两种涂层与典型缸套材料HT200灰铸铁在大气环境、纯发动机油润滑环境和模拟发动机腐蚀性油润滑环境下的摩擦学性能。结果表明:高铬铸铁涂层在腐蚀性发动机油环境中表现出好的摩擦磨损性能。 相似文献
13.
L. Jackson M. Ivosevic R. Knight R. A. Cairncross 《Journal of Thermal Spray Technology》2007,16(5-6):927-932
Polymer and polymer/ceramic composite coatings were produced by ball-milling 60 μm Nylon-11 together with nominal 10 vol.%
of nano and multiscale ceramic reinforcements and by HVOF spraying these composite feedstocks onto steel substrates to produce
semicrystalline micron and nanoscale reinforced polymer matrix composites. Room temperature dry sliding wear performance of
pure Nylon-11, Nylon-11 reinforced with 7 nm silica, and multiscale Nylon-11/silica composite coatings incorporating 7-40 nm
and 10 μm ceramic particles were characterized using a pin-on-disk tribometer. Coefficient of friction and wear rate were
determined as a function of applied load and coating composition. Surface profilometry and scanning electron microscopy were
used to characterize and analyze the coatings and wear scars. The pure Nylon-11 coating experienced less wear than the composites
due to the occurrence of two additional wear mechanisms: abrasive and fatigue wear.
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
14.
C. Marchand C. Chazelas G. Mariaux A. Vardelle 《Journal of Thermal Spray Technology》2007,16(5-6):705-712
Plasma spraying using liquid feedstock makes it possible to produce thin coatings (<100 μm) with more refined microstructures
than in conventional plasma spraying. However, the low density of the feedstock droplets makes them very sensitive to the
instantaneous characteristics of the fluctuating plasma jet at the location where they are injected. In this study, the interactions
between the fluctuating plasma jet and droplets are explored by using numerical simulations. The computations are based on
a three-dimensional and time-dependent model of the plasma jet that couples the dynamic behaviour of the arc inside the torch
and the plasma jet issuing from the plasma torch. The turbulence that develops in the jet flow issuing in air is modeled by
a large Eddy simulation model that computes the largest structures of the flow which carry most of the energy and momentum.
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.
Cold gas dynamic spraying of iron-base amorphous alloy 总被引:2,自引:0,他引:2
L. Ajdelsztajn E. J. Lavernia B. Jodoin P. Richer E. Sansoucy 《Journal of Thermal Spray Technology》2006,15(4):495-500
This paper describes recent efforts to synthesize iron-base amorphous alloys coatings using cold gas dynamic spraying. Characterization
of the gas-atomized iron-base (Fe-Cr-Mo-W-C-Mn-Si-Zr-B) powder shows that the powder is fully amorphous when the particle
diameter is below 20 μm. The coatings produced were composed of the same microstructure as the one observed in the feedstock
powder. The overall deformation suggests the occurrence of a localized deformation process at the particle/particle boundary
and a possible adiabatic deformation softening inside the powder particles during splat formation. The synthesis of fully
amorphous, porous-free coatings using cold gas dynamic spraying was demonstrated in this work.
This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials
Park, OH, 2006. 相似文献
16.
A. Arcondéguy A. Grimaud A. Denoirjean G. Gasgnier C. Huguet B. Pateyron G. Montavon 《Journal of Thermal Spray Technology》2007,16(5-6):978-990
Many substrates do not sustain the conventional glazing process (i.e., vitreous glazing) due to the relatively high temperature
required by this treatment (i.e., up to 1400 °C in some cases) to fuse glazes after their application on the surface to be
covered. Flame spraying could appear as a solution to circumvent this limitation and to avoid thermal decomposition of substrates.
This contribution describes some structural attributes of glaze coatings manufactured by flame spraying. It also discusses
the influence of the feedstock powder morphology and some of its physical properties on coating characteristics.
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.
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
18.
19.
The radial injection gas dynamic spray (RIGDS) technology of powder coatings deposition was considered for this work. A coating
was created by injecting powders with variable compositions into a supersonic air jet and depositing powder on the substrate.
This study describes the preliminary analysis of an air gas dynamic spray method realized by a portable RIGDS apparatus with
a radial injection of powder. Attention was given to shock compaction processes during the coating structure formation and
examples of powder mixtures utilization in RIGDS. It was shown that the operational parameters of supersonic powder-gas jet
have a significant influence on the coating's microstructure, thus defining the high performance of the coating. Compaction
and bonding of particles were analyzed.
The original version of this paper was published in the CD ROM Thermal Spray Connects: Explore Its Surfacing Potential, International Thermal Spray Conference, sponsored by DVS, ASM International, and HW International Institute of Welding,
Basel, Switzerland, May 2–4, 2005, DVS-Verlag GmbH, Düsseldorf, Germany. 相似文献
20.
Nanocrystalline Al−Mg coatings were produced using the cold gas dynamic-spraying technique. Unsieved Al−Mg powder of average
nanocrystalline grain size in the range of 10 to 30 nm and with a particle size distribution from 10 to >100 μm was used as
the feedstock powder. The resulting coatings were evaluated using scanning electron microscopy (SEM), transmission electron
microscopy, as well as microhardness and nanoindentation measurements. Coating observations suggest that the wide particle
size distribution of the feedstock powder has a detrimental effect on the coating quality but that it can be successfully
mitigated by optimizing the spraying parameters. Nanohardness values close to 3.6 GPa were observed in both the feedstock
powder and coatings, suggesting the absence of cold-working hardening effects during the process. The effects of the substrate
surface roughness and thickness on coating quality were investigated. The deposited mass measurements performed on the coatings
showed that the effect of using different grit sizes for the substrate preparation is limited to small changes in the deposition
efficiency of only the first few layers of deposited material. The SEM observation showed that the substrate surface roughness
has no significant effect on the macrostructures and microstructures of the coating. The ability to use the cold gas dynamic
spraying process to produce coatings on thin parts without noticeable substrate damage and with the same quality as coatings
produced on thicker substrates was demonstrated in this work.
The original version of this paper was published in the CD ROM Thermal Spray Connects: Explore Its Surfacing Potential, International Thermal Spray Conference, sponsored by DVS, ASM International, and IIW International Institute of Welding,
Basel, Switzerland, May 2–4, 2005, DVS-Verlag GmbH, Düsseldorf, Germany. 相似文献