TSA anodising voltage effects on the near-surface coarse intermetallic particles in the AA2024-T3 and AA2198-T8 alloys

In this study, the behaviour of the micrometric particles of the AA2198-T8 alloy during anodising at various voltages and the effect of anodising voltage on the anodised surface morphology have been investigated in a tartaric-sulfuric acid anodising solution. The results were compared with that of the AA2024-T3 alloy. For the AA2198-T8 alloy, partial dissolution of these particles occurred at 0, 3 and 4 V. Besides, for potentials above 5 V, there is a preferential dissolution of the intermetallic particles. For the AA2024-T3 alloy, the results indicated a total dissolution of the micrometric particles at 0 V and a partial dissolution at 3 V, whereas above 4 V total dissolution occurred. Between 1 and 2 V, no dissolution was observed for both alloys. The preferential dissolution of the micrometric particles resulted in defects in the anodic film and cavities on the anodised surfaces.

Automated summary

The behavior of micrometric particles in the AA2198-T8 and AA2024-T3 alloys during anodizing at different voltages was investigated in this study. The results showed that the dissolution of particles varied with voltage, and the dissolution process resulted in the formation of defects and cavities on the anodized surfaces.