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71.
X. Q. Ma H. Zhang J. Dai J. Roth R. Hui T. D. Xiao D. E. Reisner 《Journal of Thermal Spray Technology》2005,14(1):61-66
This work addresses the fabrication of membrane-type solid oxide fuel cells (SOFCs) operating at medium temperatures, where
all components are fabricated by plasma spray technology, and the evaluation of the performance of the SOFC single unit in
a temperature range of 500 to 800 °C. Single cells composed of LaSrMgO3 cathodes, LaSrGaMgO3 (LSGM) electrolytes, and Ni/yttria-stabilized zirconia anodes were fabricated in successive atmospheric plasma-spraying processes.
Plasma-spraying processes have been optimized and tailored to each layer to achieve highly porous cathode and anode layers
as well as high-density electrolyte layers. A major effort has been devoted to the production of the LSGM electrolyte that
has a high density and is free of cracks. Electrochemical impedance spectroscopy was used to investigate the conductivity
of the electrode layers, and particularly the resistance of the electrolyte layer. It revealed that the heat treatment had
a great influence on the specific conductivity of the sprayed electrolyte layers and that the specific conductivity of the
heat-treated layers was dramatically increased to the same magnitude as is typical for sintered LSGM pellets. The experimental
results have demonstrated that the plasma-spraying process has a great potential for the integrated fabrication of medium-temperature
SOFC units.
The original version of this article was published as part of the ASM Proceedings, Thermal Spray 2003: Advancing the Science and Applying the Technology, International Thermal Spray Conference (Orlando, FL), May 5–8, 2003, Basil R. Marple and Christian Moreau, Ed., ASM International,
2003. 相似文献
72.
本文通过研究目前汽车烤漆房的实际运行情况,提出了一种汽车烤漆房喷漆自动控制系统,阐述了系统喷漆装置的构成、配合与运行原理,并构成了实际试验系统。 相似文献
73.
Thermal sprayed aluminum and zinc provide long-term (> 20 years to first maintenance) corrosion control coatings. However,
this application is usually more expensive than painting or galvanizing if thermal spraying (metallizing) is not integrated
into the design and fabrication phases of new construction and repair projects. Aluminum and zinc metallized coatings are
tough enough to withstand fabrication, transportation, and assembly operations. The improved capabilities and productivity
of metallizing equipment for aluminum and zinc spraying are a major factor in their current cost competitiveness. The net
result is that the cost difference between metallizing, paint, and galvanizing is getting closer every day. Even though the
initial application cost of metallizing may be higher, the life cycle cost (LCC) and average equivalent annual costs (AEAC)
are lower than paint coating systems. Metallizing LCCs, when properly engineered into the construction schedule, are equal
to or less than paint coating LCCs. This article summarizes some metallizing considerations for installing improved corrosion
control coating systems in new construction and in maintenance and repair of infrastructure.
Editor’s Note: The following constants have been used to convert between English and Metric dimensions: 1ft2-0.0929 m2; 1lb/ft2-4.89 kg/m2; 1 mil=0.025mm.
Presented at the 5th National Thermal Spray Conference (NTSC-93), Infrastructure Maintenance and Repair Session, 10 June 1993,
Anaheim, CA. 相似文献
74.
Marine antifouling coating using functional polymers has emerged as an important tool to combat marine fouling. Owing to their natural abundance, polysaccharides represent a more sustainable option than synthetic polymers and carrageenan, a sulfated polysaccharide, is identified as a promising candidate for further research based on its excellent marine antifouling properties. However, existing research has only explored the application of carrageenan-based coatings for 2D objects, using techniques such as spin-coating. Here, a spray-coating method is proposed to apply carrageenan-based coatings to the surfaces of 2- and 3-D objects. The coated surfaces exhibit high stability under various chemical/physical stresses and high resistance to protein adsorption and marine diatom adhesion. 相似文献
75.
The deposition of copper by cold gas dynamic spraying has attracted much interest in recent years due to the capability to
deposit low-porosity oxide-free coatings. However, it is generally found that as-deposited copper has a signicantly greater
hardness, and potentially lower ductility, than bulk material. In this article, copper was deposited by cold spraying using
helium as the driving gas at both 298 and 523 K. Evidence is presented indicating that the material sprayed at the lower temperature
exhibits a lower dislocation density throughout the grain structure than the material sprayed at the higher temperature. The
low stacking fault energy of copper restricts recovery during annealing, and thus microstructural changes during annealing
only proceed once recrystallization begins. The material sprayed at low temperature (with the low dislocation density) exhibited
recrystallization at annealing temperatures as low as 373 K with a corresponding reduction in hardness. However, the copper
sprayed with helium at 523 K was resistant to annealing at temperatures up to 473 K where the dislocations in the structure
prevented recrystallization. However, at higher temperatures, recrystallization did proceed (with corresponding reductions
in hardness). The fracture behavior of the copper that was cold sprayed with helium at 523 K, both in the as-sprayed condition
and following annealing, was measured and explained in terms of the annealing mechanisms proposed.
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
76.
The characterization of La
x
Sr1−x
MnO3 powders produced by spray pyrolysis using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) observation,
specific surface area (Brunauer-Emett-Teller), and particle size distribution measurements shows that the resultant large
particles are loose agglomerates consisting of many small particles. However, the sintered tiny particles can form hard agglomerates,
and the particle size increases remarkably. The structures of the powders before and after sintering were identified by x-ray
diffraction (XRD). The study of the electrical property of the powder shows that the powder is a metallic conductor. In a
reducing atmosphere, the powder can be decomposed. When the powder is cofired with yttria-stabilized zirconia 5% (YSZ) powder
at 1200 °C for 5 h, no new phase is produced, and the powder remains a single provskite hexagonal-rhombohedral structure. 相似文献
77.
介绍了石油工业的发展形式,提出防腐保温技术专业委员会今后工作的重点应放在推进技术创新、加强技术培训和加强会员企业的诚信建设等方面,以适应石油工程建设的需要。 相似文献
78.
K. A. Khor F. Y. C. Boey Y. Murakoshi T. Sano 《Journal of Thermal Spray Technology》1994,3(2):162-168
There has been increasing use of Al-Li alloys in the aerospace industry, due mainly to the low density and high elastic modulus
of this material. However, the problem of low ductility and fracture toughness of this material has limited its present application
to only weight- and stiffness-critical components. Development of Al-Li/ceramic composites is currently being investigated
to enhance the service capabilities of this material. The Ti-Al alloy is also of interest to aerospace-type applications,
engine components in particular, due to its attractive high-temperature properties. Preparation of fine powders by plasma
melting of composite feedstock and coatings formed by plasma spraying was carried out to examine the effect of spray parameters
on the microstructure and properties of these materials. Characterization of the powders and coatings was performed using
the scanning electron microscope and image analyzer. Examination of the plasma-sprayed powders and coatings has shown that
in the Al-Li/SiC composite there is melting of both materials to form a single composite particle. The SiC reinforcement was
in the submicron range and contributed to additional strengthening of the composite body, which was formed by a cold isostatic
press and consolidated by hot extrusion or hot forging processes. The plasma-sprayed Ti-Al powder showed four categories of
microstructures: featureless, dendritic, cellular, and martensite-like. 相似文献
79.
针对铝电解原材料中AlF3与Al2O3自动配料不准和难于观察及控制的现象,我厂开发应用了AlF3贮仓料位计,并与微机网络相连,实现了远程测量与在线监控,使AlF3配料更准确更均匀,电解质分子比更稳定,电解槽生产低耗高效。 相似文献
80.