CeCl3和苯并三唑对自然时效和人工时效AA2024铝合金耐蚀性的协同效应(英文)

分析自然时效和人工时效AA2024铝合金在0.5 mol/dm³ NaCl溶液中的腐蚀行为,溶液中分别加入环境友好的缓蚀剂:10 mmol/dm³ CeCl₃,10 mmol/dm³ BTA和5 mmol/dm³ CeCl₃+5 mmol/dm³ BTA混合缓蚀剂。本研究的目的是确定混合缓蚀剂的协同效应水平,并解释这种效应的本质。采用电化学阻抗谱(EIS)研究缓蚀剂层的腐蚀性能,通过动电位极化试验研究其抑制点蚀形成和点蚀生长的能力。扫描电子显微镜(SEM/EDS)的结果表明,自然时效铝合金中形成的点蚀尺寸小于人工时效合金中形成的点蚀尺寸。在自然时效合金测试的96 h内以及在人工时效合金测试的后期,均观察到混合缓蚀剂对腐蚀性能的协同效应,但没有发现混合缓蚀剂对点蚀形成和点蚀生长的协同效应。

Synergistic effect of CeCl3 and benzotriazole on corrosion resistance of naturally aged and artificially aged AA2024 aluminium alloy

The corrosion behaviours of naturally aged and artificially aged AA2024 aluminium alloys in 0.5 mol/dm³ NaCl solution in the presence of environmentally friendly corrosion inhibitors of 10 mmol/dm³ CeCl₃, 10 mmol/dm³ BTA and the inhibitor mixture (5 mmol/dm³ CeCl₃ + 5 mmol/dm³ BTA) were analyzed. The goal of this work was to determine the level of the synergistic effect of the inhibitor mixture and to explain the nature of this effect. Corrosion properties of the inhibitor layer were studied using the electrochemical impedance spectroscopy (EIS), while the resistance to pit formation and pit growth was studied by applying potentiodynamic polarisation tests. The results of scanning electron microscopy (SEM/EDS) showed that the size of pits formed in naturally aged aluminium alloy was smaller than that formed in artificially aged alloy. The synergistic effect of the inhibitor mixture on corrosion properties of naturally aged alloy was observed throughout 96 h, and in later phases of testing of artificially aged alloy. The synergistic effect of the inhibitor mixture was not noticed on pit formation and pit growth.