IFISUR   23398
INSTITUTO DE FISICA DEL SUR
Unidad Ejecutora - UE
artículos
Título:
Corrosion of Fe-25Cr-20Ni-0.40C alloy: an experimental and computational Study
Autor/es:
C. LANZ; G. BRIZUELA; S. SIMONETTI
Revista:
International Journal of Research in Advanced Engineering and Technology
Editorial:
IJRAET
Referencias:
Año: 2016 vol. 2 p. 7 - 9
Resumen:
The investigation combines microstructural characterization analyses and atomistic modeling to elucidate the mechanism ofcarburization embrittlement of an iron-nickel-chromium alloy exposed to high temperature. It was studied an austenitic Fe-25Cr-20Ni-0.40C stainless steel obtained of the tubes of the industrial cracking furnace after 25,000 h of service at 900-1200 ºC. Theservice-exposed material presented bigger carbides in the austenitic matrix comparing with the as-cast material, cavities betweenthe grains and micro fissures in grain edges, indicating that the material present damage by creep. The theoretical calculations helpus to interpret the changes in the alloy electronic structure and the chemical bonding. The atomic orbital occupations of themetallic bonds are affected during carburization. The strengths of the, Cr-Ni, Fe-Cr, Fe-Ni and Ni-Ni bonds nearest neighbors tothe carbon atoms are the most affected. The metallic bond weakening is mainly a consequence of the new C-Ni, C-Fe and C-Crinteractions formed after carburization phenomena.