The use of ceramic materials in the production of solid oxide fuel cells (SOFCs) is one of the most innovative applications of these materials in recent years. The aim of this work is to assess how to obtain a complete, self-assembled SOFC (supported by electrolyte) using atmospheric plasma spray (APS) to spray the three different ceramic layers of the assembly. One of the main problems of SOFC production is the high cost of the process; the hypothesis is that these costs can be reduced by forming the three ceramic layers of the SOFC by APS technology. The anode (YSZ-NiO), cathode (LSM), and electrolyte (YSZ) layers can be produced by APS with reasonable efficiency. Another problem with SOFC manufacture is assembly and adhesion of the three layers; the creation of gradual transition layers by APS improves these aspects of the production process. Chemical and structural characterization of the feedstock powders and resultant ceramic layers was performed by laser scattering, XRD, SEM, and confocal microscopy, and the results confirmed the efficiency of the attained APS-SOFC components.

Corrosion is a very important problem in the Municipal Solid Waste Incinerator (MSWI) superheaters. This problem causes the plant stops and tube replacements, promoting the loss of energy generation rate. The main corrosion agent is the chlorine deposits. HVOF coatings have been sprayed to improve corrosion resistance of the superheaters inside the MSWI boilers. Inconel 625 and Hastelloy C22 alloys have been sprayed as a powder feedstock material. The spray process has been analyzed by a Spray Watch system that allows carrying out the temperature and velocity measurements of the particles in flight in order to optimize the spraying process. The produced coatings have been characterized by Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) to evaluate the porosity and oxidation produced in the spray process. Laboratory oxidation test have revealed the formation of Cr 2 O 3 , NiO and Fe 2 O 3 as corrosion products as well as Microanalysis by Energy dispersion Spectroscopy (EDS) composition profiles have been used to evaluate the penetration of the corrosion front inside the coating. The Nickel alloys show a good resistance in aggressive environment test and can be a good solution for the corrosion problems in the superheater tubes in MSWI.

Steel tubes oxidation causes an important problem in Municipal Solid Waste Incinerator plants (MSWI). This work shows a possible solution for this problem through High Velocity Oxygen Fuel (HVOF) thermal spray coatings. A comparison between powder and wire thermal spray coatings (with the same composition) has been done. These optimised coatings have been compared through their microstructure, wear properties (ASTM G99-90, ASTM G65-91), and erosion-corrosion (E-C) resistance. Results of the different EC tests designed in the Thermal Spray Centre, have been evaluated by X Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Energy Disperse Spectroscopy (EDS). Commercial bulk material with similar composition of Ni Based coatings has also been tested. The protection mechanisms of these materials have been assessed after studying the results obtained by HVOF coatings and bulk material. Ni based HVOF coatings are a promising alternative to the MSWI conventional protection against chlorine environments.