This study explores stability and variations of a mercaptobenzimidozole-inhibitor-based film upon the surface of Al alloy AA6022 and its contribution to the long-term corrosion inhibition in 0.1 M NaCl. Results provide a deeper insight and understanding of the mechanisms of combined inhibitor film formation and oxide layer growth, up to 240 h exposure, and the effect that the intermetallic particles have on the resultant film stability within these regions. Electrochemical impendence spectroscopy (EIS), potentiodynamic polarization (PDS) and X-ray photoelectron spectroscopy (XPS) studies reveal the formation of a porous, defective oxide layer on the alloy surface under uninhibited conditions. The addition of inhibitors results in the creation of a cathodically controlled system and the formation of a thin inhibitor-oxide mixed film, through the chemical absorption of inhibitor molecules to the substrate via S atom in association with O, thus reducing the corrosion rates. Focus ion beam scanning electron microscopy further confirms the presence of a combined oxide layer and inhibitor film, which covered both the alloy matrix and intermetallic regions. In addition, activity reduction of the Fe rich IMPs is thought to have occurred.

这项研究探索了在铝合金AA6022表面上巯基苯并咪唑抑制剂基薄膜的稳定性和变化及其对0.1 M NaCl中长期腐蚀抑制的贡献。结果提供了对抑制剂膜形成和氧化物层生长的组合机理（长达240小时的曝光）的更深刻的了解和理解，以及金属间颗粒对这些区域内所得膜的稳定性的影响。电化学阻抗谱（EIS），电势极化（PDS）和X射线光电子能谱（XPS）研究表明，在不受抑制的条件下，合金表面上会形成多孔的有缺陷的氧化物层。抑制剂的加入导致抑制剂控制的体系的建立，并通过抑制剂分子通过与O结合的S原子将吸收剂分子化学吸收到基底上，从而形成了阴极-氧化物混合薄膜，从而降低了腐蚀速率。聚焦离子束扫描电子显微镜进一步证实了覆盖了合金基体和金属间区域的复合氧化物层和抑制剂膜的存在。另外，据认为已经发生了富铁IMP的活性降低。