On the severe localized corrosion susceptibility of the AA2198-T851 alloy

The time dependent susceptibility of AA2198-T851 Al-Cu-Li alloy to severe localized corrosion in 0.01 mol L-1 NaCl solution has been investigated by immersion and SVET tests. The results reveal that the propagation of severe localized corrosion, in the alloy, is crystallographic and it is associated with the slip bands in the individual grains of the alloy. The slip bands caused uneven precipitation of the active T1 particles. Also, oscillations in SVET current density values associated with deposition and detachment of corrosion products were observed. Furthermore, the intensity of corrosion activities increased over time for open or partially covered pits.