Compara????o do comportamento de corros??o da liga convencional AA2024-T351 e da liga Al-Li 2098-T351

• Autor(a) principal: MILAGRE, M.X.
• Data de Publicação: 2017
• Outros Autores: ARAUJO, J.V., QUEIROZ, F.M., MACHADO, C.S.C., COSTA, I., CONGRESSO BRASILEIRO DE ENGENHARIA E CIENCIA DOS MATERIAIS, 22.
• Tipo de documento: Artigo de conferência
• Título da fonte: Repositório Institucional do IPEN
• Texto Completo: http://repositorio.ipen.br/handle/123456789/27294
• topic: aluminium alloys; corrosion resistance; lithium alloys; optical microscopy; pitting corrosion; scanning electron microscopy; sodium chlorides

In this work, the localized corrosion behavior of an Al-Li alloy (AA2098-T351) was compared with that of the AA2024-T351 conventional alloy by immersion test in 0.01 mol L-1 NaCl solution. The evolution of localized corrosion in both alloys was monitored by optical microscopy and scanning electron microscopy after several test periods from 2h to 24h. The results showed high susceptibility of the two alloys to pitting from the early hours of immersion. The corrosion mechanism in the two alloys, however, was different. Localized corrosion in the AA2024 alloy was associated with the microcells generation between micrometric precipitates and the matrix leading to superficial attack homogeneously distributed throughout the surface exposed to the corrosive environment. In the AA2098 alloy, however, a severe localized corrosion ascribed in the literature to the presence of phase T1 was also observed besides the localized corrosion type similar to that observed in the AA2024 alloy.