Abstract

BARON, Yliana S; NAVAS, Gladys  and  RUIZ, Augusto. Mecanismo de oxidación de un acero 1,25Cr-0,5Mo Wt% en aire a 600ºC. Rev. LatinAm. Metal. Mater. [online]. 2010, vol.30, n.1, pp.40-45. ISSN 0255-6952.

The mechanism of oxidation of a 1,25Cr-0,5Mo steel at 600 ºC was evaluated. The characterization of the crosssections of oxidized samples was performed with scanning electron microscopy (SEM-EDX). It was found that there is an immobile interface marked by the presence of chromium. This chromium oxide is formed by internal oxidation of this element present in the steel. It also was found that wustite and magnetite are formed due to outward cationic diffusion, but hematite is formed by the reaction between interstitial iron ions and oxygen. Thus, the oxidation rate depends of the stability of the magnetite. These results were also evaluated by the weight gain curve obtained with a thermo-balance.

Keywords : oxidation; 1,25Cr-0,5Mo steel.