Revista Ion (Jun 2014)
Oxidación en vapor de agua del acero inoxidable AISI 316 recubierto con Al-Si por deposición química de vapor en lecho fluidizado
Abstract
Stainless steel AISI 316 was coated with aluminum-silicon by Chemical Vapor Deposition in Fluidized Bed Reactor (CVD-FBR) to 540°C and subsequently heat treated to improve its mechanical properties and its behavior against oxidation, by inter diffusion of the alloying elements. Later, oxidation was performed austenitic stainless steel aluminum-silicon coated at temperatures of 700 and 750°C, in an environment with 100% steam, to evaluate their performance. Mass gain graphs were made and oxide films were analyzed by SEM and X-ray diffraction to observe the morphology of the oxides. Thermodynamic simulation was carried out during oxidation in water vapor of the substrates for possible solid phases which could be formed. The form of attack at 750°C is similar to 700°C, although the rate of oxidation is increased, because the diffusion of the alloying elements and the oxidation reactions are faster. These coatings have good resistance to oxidation in water vapor and forming an alumina surface layer which protects the substrate from corrosion attack.
