摘要
通过动电位极化使LY12铝合金表面产生点蚀后分别涂刷富镁涂层和环氧涂层,利用电化学阻抗等方法研究了富镁涂层对于铝合金基体点蚀的作用。结果表明:富镁涂层使铝合金的开路电位发生明显的负移,并在较长时间保持稳定,基体发生腐蚀的时间显著延迟,说明富镁涂层对于铝合金具有明显的阴极保护作用;点蚀的存在使得富镁涂层中的镁粉溶解速率加快,能更有效地保护基体;富镁涂层试样的铝合金基体浸泡后点蚀无明显的发展,说明富镁涂层能够一定程度上抑制铝合金表面点蚀的生成及发展。
Mg-rich coating and epoxy coating were painted respectively on the surface of LY12 aluminum alloy with pits prepared through potentiodynamic polarization. The effect of Mg-rich coating on pitting corrosion of aluminum alloy substrate was studied with electrochemical impedance spectroscopy （EIS）. Results show that the Mg-rich coating could make the open circuit potential of aluminum alloy move negatively and maintained it stable for an extended period, showing good cathodic protection for aluminum alloy. The time for corrosion of the A1 suhstrate was significantly prolonged. On the A1 suhstrate with pits the dissolution rate of Mg particles in the coating increased, which would protect the substrate more effectively. The pits on the substrate surface showed no obvious changes for the Mg-rich coated sample, indicating that the Mg-rich coating could inhibit the generation and development of pitting corrosion on the aluminum alloy to some extent.
出处
《腐蚀与防护》
CAS
北大核心
2016年第8期648-652,共5页
Corrosion & Protection
关键词
铝合金
富镁涂层
点蚀
阴极保护
aluminum alloy
Mg-rich coating
pitting corrosion
cathodic protection
