Influence of the Processing Method on the Quality of the Protective Coatings for SOFC Applications
Résumé
Protective layers for Solid Oxide Fuel Cells (SOFC) interconnects (IC) were developed. The contacting layers are made of La0.8Sr0.2Mn0.5Co0.5O3 (LSMC) and were prepared by wet powder spraying. In order to avoid IC oxidation and a dramatic increase of ASR, MnCo2O4 spinel protective coatings were processed either by Atmospheric Plasma Spraying (APS) or by a Metal Organic route (MO). The influence of the processing method of these layers on the resistance of their assembly with an IC was investigated on Crofer22APU and F17TNb substrates. The measured ASR is stable after about one hundred hours. Their efficiency in Single Repeated Unit (SRU) configuration was also investigated. The MO process gave the thinnest layer, thereby the lowest resistance. The APS process gives thicker and denser layers, thus preventing completely the chromium diffusion through the cathode, but a slightly higher resistance is observed.