Papers by Keyword: FeCrAl Steel

Abstract: The investigations were aimed to characterize the oxide films (Al₂O₃) in terms of the crystal structure development and their impact on increase in mechanical distribution of Pt in volume of the film, as a system predisposed to carry out catalytic processes. The morphology and phase composition of oxide films formed on the surface of FeCrAl steel foil coated with Al and Pt films and Al/Pt composition films after oxidation at high temperature were investigated. All samples with films were oxidized in an atmosphere containing 67% O₂/Ar at 850 ° C in a period of 24 h. As a result of the oxidation processes there were formed θ-Al₂O₃ oxides of whisker structure of a considerable size, while whiskers of θ-Al₂O₃ oxides formed on the samples coated with Pt films were smaller but with higher density. There was also α-Al₂O₃ phase in the form of solids in the immediate vicinity of the steel substrate.

Abstract: Good dispersion of active catalytic elements, their uniform distribution on the carrier’s surface and availability for neutralised combustion gases are key factors that determine the usability of catalyst cartridges for automotive catalytic reactors. By examining the morphology of oxide films, with SEM/STEM method, obtained by oxidation of foil coated with Pt/Al two-layered system (like laminate), where an Al nanofilm is situated between steel foil and a Pt nanofilm, one can observe forked and plate whiskers growing directly of substrate. Oxide films obtained from Pt+Al composite nanofilms were formed differently (where components are intermixed). These films are marked by chaotic, mutually penetrating fine equiaxed solids and whiskers. In case of composite nanofilms the grain system obtained in the course of deposition contributed to good Pt grain refining, and due to that mostly particles from 3 to 9 nm in conventional diameter were formed. Direct contact between Pt particles and Al particles caused the partial occlusion of Pt particles with oxide in the process of Al oxidation to be effected.