INFLUENCE OF LASER TREATMENTS ON THE CORROSION BEHAVIOUR OF TITANIUM ALLOYS

摘要

Due to their high strength, low density and excellent resistance to corrosion and oxidation, titanium and titanium alloys are widely employed in different fields, such us medical, aerospace, automotive, petrochemical, nuclear and power generation industries. The heat treatments are known to modify the properties of these alloys. In the present contribution, the influence of different laser treatments on the properties of two titanium alloys (TiG2 and T16AI4V) is studied. The influence of experimental variables, as the laser power and the processing rate, on the microstructure, microhardness and the corrosion behaviour of the samples was investigated. The laser treatments were performed with a High Power Diode Laser. Several parallel laser scans were made over the samples, with the objective of having enough affected area to perform the corrosion tests. Not treated samples were also studied for comparative purposes. The corrosion behaviour of the samples was analysed by means of linear polarisation tests, which allowed the estimation of the polarisation resistance parameter (R_p).