Comparison of corrosion behaviour of nanocrystalline 2024-T4 Al alloy processed by surface mechanical attrition treatment with two different mediums

摘要

The pure nanocrystalline Al layer and Fe containing nanocrystalline layer were fabricated on the surface of 2024 Al alloy by surface mechanical attrition treatment (SMAT) with two different mediums, ceramic balls and steel balls, respectively. The corrosion behaviour of 2024 Al alloy before and after SMAT was investigated by potentiodynamic polarisation curves and electrochemical impedance spectroscopy (EIS). The electrochemical tests demonstrated that the nanocrystalline layer fabricated by SMAT with ceramic balls improved the corrosion resistance of 2024 Al alloy, while the Fe containing layer induced by SMAT with steel balls led to the diminution in the corrosion resistance.