Publicado 4 números por año
ISSN Imprimir: 1093-3611
ISSN En Línea: 1940-4360
Indexed in
UNDERSTANDING OF SUSPENSION PLASMA SPRAYING
SINOPSIS
The aim of this paper is to present the recent advances regarding the Suspension Plasma Spraying process (SPS). The latter is devoted to synthesize finely structured coatings which are of great interest for the electrolytes (of low thickness, 20-30 μm) of Solid Oxide Fuel Cells (SOFC). Powders of Yttria (13.5wt%) Stabilised Zirconia (YSZ) are dispersed in ethanol to produce a stable suspension. The latter is injected by using a mechanical injection into a plasma jet generated by a DC plasma torch. Four centimetre square coatings are built with a deposition efficiency ranging between 50 and 60 % and a deposition rate up to 15 μm.h−1.m−2.
The injection pressure of suspensions is optimized by using a pulsed infra-red illumination of the atomization processes of suspensions which is observed with a fast shutter camera.
The influences of the preheating and roughness of the substrates, the plasma gas composition and the particle size distribution on the flattening degree of collected splats are investigated. Moreover, the effect of these experimental parameters on the coating microstructures is then studied. It is shown that substrates have to be polished and preheated to enable the most favorable flattening of splats. Moreover, the particle size distribution of powder in suspension has to be narrow with a size adapted to the spraying conditions, for example, centered on about l μm for a plasma enthalpy of 17.5 MJ.kg−1. The results about splats are confirmed when analyzing coating microstructures which present micro-sized porosity.
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Ravi B.G., Gandhi Ashutosh S., Guo X.Z., Margolies J., Sampath S., Liquid Precursor Plasma Spraying of Functional Materials: A Case Study for Yttrium Aluminum Garnet (YAG), Journal of Thermal Spray Technology, 17, 1, 2008. Crossref
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Waldbillig D., Kesler O., Characterization of metal-supported axial injection plasma sprayed solid oxide fuel cells with aqueous suspension plasma sprayed electrolyte layers, Journal of Power Sources, 191, 2, 2009. Crossref
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Arevalo-Quintero O., Waldbillig D., Kesler O., An investigation of the dispersion of YSZ, SDC, and mixtures of YSZ/SDC powders in aqueous suspensions for application in suspension plasma spraying, Surface and Coatings Technology, 205, 21-22, 2011. Crossref
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Fauchais Pierre, Vardelle Armelle, Thermal Plasmas Surface Treatment, in Materials Surface Processing by Directed Energy Techniques, 2006. Crossref
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Zou Zhonghua, Donoghue Jack, Curry Nicholas, Yang Lixia, Guo Fangwei, Nylén Per, Zhao Xiaofeng, Xiao Ping, A comparative study on the performance of suspension plasma sprayed thermal barrier coatings with different bond coat systems, Surface and Coatings Technology, 275, 2015. Crossref
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Chidambaram Seshadri Ramachandran, Dwivedi Gopal, Viswanathan Vaishak, Sampath Sanjay, Characterizing Suspension Plasma Spray Coating Formation Dynamics through Curvature Measurements, Journal of Thermal Spray Technology, 25, 8, 2016. Crossref