采用动电位电化学阻抗谱技术研究了不同电位条件下S22053不锈钢在6%（质量分数）FeCl₃溶液中的点蚀行为。结果表明，电位为0.3~0.9 V（SCE，下同）时，S22053不锈钢处于稳定的钝化状态；电位为1.0 V时，钝化膜上诱导点蚀；电位为1.1~1.2 V时，蚀坑持续扩展，且以向蚀坑深处扩展为主；电位为1.3~1.4 V时，新的点蚀在钝化部位诱导产生。点蚀发生后，电化学阻抗谱主要表征蚀坑处的特征。

Pitting behavior of S22053 stainless steel in 6% (mass fraction) FeCl₃ solution under different potential conditions was studied by potentiodynamic electrochemical impedance spectroscopy. The results show that when the potential was 0.3~0.9 V (SCE, the same below), S22053 stainless steel was in a stable passivation state; and when the potential was 1.0 V, pitting was induced on the passivation film. When the potential was 1.1~1.2 V, the etch pit continued to expand, and mainly expanded to the depth of etch pit; and when the potential was 1.3~1.4 V, new pitting was induced at the passivation site. After pitting occurred, the electrochemical impedance spectroscopy mainly characterized the characteristics of etch pit.