关键词: Ti₂AlC, 点腐蚀, 晶间腐蚀, 剥蚀, 极化曲线

Abstract: 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.

Key words: Ti₂AlC, pitting, intergranular corrosion, exfoliation, polarization curves