Corrosion Behavior of Nitrided Ni₃Al Intermetallic Alloy in 0.5 M H₂SO₄

摘要

The effect of plasma nitriding on the corrosion behavior of Ni3Al intermetallic alloy in 0.5 M H2SO4solution at 60 0C has been investigated by using potentiodynamic polarization curves, electrochemicalimpedance spectroscopy (EIS) and linear polarization resistance (LPR) measurements. Specimens wereplasma nitrided at 500 and 6000C during 8, 16 and 24 hours and were characterized by x-ray diffractionand scanning electronic microscopy. Results have shown that the thickness of nitride layer increasedwith nitriding time and temperature. Passive film properties were improved by nitriding. The corrosionresistance of nitride specimens increased with an increase either in the nitriding time or temperature.Specimens were susceptible to both uniform and localized types of corrosion.