Deposition of La-Sr-Fe-Co Perovskite Coatings with Different Microstructures by Low Pressure Plasma Spraying

Preparation of La_1-xSr_xFe_1-yCo_yO_3-δ (LSFC) coatings by plasma spraying at low pressure (200 Pa) using different plasma spray parameters is reported and discussed. Deposition with Ar-He plasma leads always to formation of coatings containing a mixture of LSFC perovskite, SrLaFeO₄, FeCo and metal oxides. Coatings deposited at higher oxygen partial pressures by addition of oxygen into the vacuum chamber contain more than 85% perovskite and only few percent Fe₃O₄ and/or CoO. The microstructures of the investigated LSFC coatings depend sensitively on the oxygen partial pressure, the substrate temperature and the deposition rate.