Influence of Ti and Cu on the corrosion properties of laser-deposited high entropy alloys

Abstract

In this study, AlCoCrFeNiCu (Cu-based) and AlCoCrFeNiTi (Ti-based) high entropy alloys were fabricated using laser additive manufacturing. The influence of the alloying elements and the laser processing parameters, the laser power and scanning speed on the corrosion behaviour of high entropy alloys for improved corrosion resistance were examined. The corrosion resistance in 1 mol/L sodium hydroxide solution was investigated using potentiodynamic polarization in experimental conditions at ambient temperature. Results indicate that the scan speed and laser power are two interactive factors that influence the corrosion rates, however, the laser power had more influence. Optimization occurred at 1400 W laser power and a scan speed of 10 mm/s. The Cu-based alloy with a corrosion rate of 0.00197 mm/yr was more resistant to corrosion than the Ti-based alloy with corrosion rates of 0.002635 mm/yr under optimum conditions.