THE EFFECT OF LSM CORROSION PROTECTION ON AL ALLOYS

Laser surface treatment has been recognized as a useful method for corrosion protection of surfaces as a result of improved microstructure/phase formation and compositions. Therefore, Laser surface treatment techniques, including laser surface melting (LSM) has been the subject of considerable interest as a means of enhancing the corrosion performance of aluminum alloys. In this research, disc samples of (7075, 6061 and 5083) aluminum alloys have been prepared, polarization tests were carried out under static condition in a different concentration of NaCl solution (1.5, 2.5, 3.5) %wt at 25oC. The experiments were carried out before and after laser surface melting by (Nd: YAG, MED-810) pulse laser, system (Q-Switched Nd: YAG 1064/532nm) After the laser melting, the surface showed a significant reduction in the number of large intermetallic particles and relatively homogenous melted layer generated that provided significant improvement in the resistance of the alloy against corrosion, as assessed by corrosion test and X-RAY Diffract (XRD) test.