Corrosion behaviour of laser remelted aluminium alloy

摘要

The laser surface melting of AA2024-T3 alloy modifies a structure of surface layer resulting in cells and/or cellular dendrites of very fine microstructure. There are mainly two phases, i.e. primary solid solution and precipitated Al_2Cu phase, around the cell boundaries. Some minor traces of Fe and Mn are also present. The estimated decrease of Cu content in precipitates is approximately 25%. The susceptibility to pitting corrosion of laser melted AA2024-T3 surfaces characterised by pitting potential was not improved in comparison with as-received material, mainly due to non-uniform structure at subsequent laser tracks.