Corrosion Behavior of Layered Ternary Carbide Ti_2AlC in Acidic Solution

High-purity,fully dense Ti2AlC samples were synthesized by hot pressing process.Their corrosion rate and corrosion type after immersed in concentrated and dilute HNO3,HCl and H2SO4 were obtained.The corrosion potential,corrosion current and potentiodynamic polarization curves were measured by electrochemical methods.Corrosion process is pitting at first,then intergranular corrosion,while exfoliation at last.The corrosion rate increases with time.The corrosion rate reaches the biggest in concentrated HNO3 while reaches the slowest in dilute HCl.The corrosion rate in the concentrated solution is faster than that in dilute solution,except in H2SO4.Electrochemical test shows the corrosion current reaches the biggest in the dilute H2SO4 and reaches the smallest in dilute HNO3.Ti2AlC shows passive behavior in all acid solution,and the passivation interval is the widest in dilute H2SO4.