Catalytic behavior of plasma-sprayed Al-Al2O3 coatings doped with metal oxides

Reactive plasma spraying of aluminum and Al(OH)(3) powders with oxide addit ives, CuO and Cr2O3, was investigated. An arc-plasma spray gun was construc ted with the injection of powders into the plasma torch both internally and externally. The spraying was done at atmospheric pressure in a working gas comprising an argon/air mixture. The resulting oxide-doped Al-Al2O3 coatin gs, which were 30-50 mu m thick, were investigated by X-ray diffraction and scanning electron microscopy. Their catalytic behavior was identified obse rving by the combustion effect of propane in a tube furnace. (C) 2000 Elsev ier Science S.A. All rights reserved.