High power diode laser treatments for improving corrosion resistance of A380/SiCp aluminium composites

Laser surface melting (LSM), using a high power diode laser, was used to modify the electrochemical behaviour of A380/SiC/xxp aluminium composites in aerated 3.5 wt.% NaCl solution. Corrosion mechanism was determined by potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), scanning Kelvin probe force microscopy (SKPFM) and low-angle X-ray diffraction (XRD). Laser-treated surface revealed a refined microstructure with homogeneous microdendrites, good matrix/reinforcement bonding and absence of cathodic intermetallic compounds. As a result, laser treatment increased the surface hardness and reduced localised corrosion attack.