Interaction of Ce(dbp)3 with surface of aluminium alloy 2024-T3 using macroscopic models of intermetallic phases

The mechanism of corrosion inhibition by cerium(III) dibutylphosphate [Ce(dbp) 3 ] on aluminium alloy 2024-T3 (AA2024-T3) has been investigated using macroscopic models of the intermetallic (IM) phases in the alloy. Polished specimens of pure Al (99?999%) and the macroscopic IM phases Al 2 CuMg, Al 7 Cu 2 Fe and Al 3 Fe were each coupled to a large surface area of AA2024-T3 to simulate the interaction they experience in the alloy. Samples were immersed in 0·1M NaCl with 200 ppm Ce(dbp) 3 for 24 h, and the resulting surfaces characterised by scanning electron microscopy, X-ray photoelectron spectroscopy, Rutherford backscattering spectroscopy and Raman spectroscopy. Ce(dbp) 3 was found to interact differently with each of the different phases examined, providing evidence for a multifunctional corrosion inhibition mechanism. © 2009 Institute of Materials, Minerals and Mining.