Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《中国腐蚀与防护学报》
Abstract: The synergistic corrosion inhibition effect related with inhibitors and synergistic agents was firstly introduced. Then the research progress of synergistic corrosion inhibition effect worldwide in recent years was summarized. The different synergistic combinations were classified into nine categories according to the sorts of corrosion inhibitors and synergistic agents, while the synergistic mechanisms were discussed. Furthermore, the research directions in the future on synergistic inhibition effect were prospected as well.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract: Corrosion behaviour of four cast magnesium alloys (ZK60, AM60, AZ31 and AZ91D) was investigated in a simulated body fluid (SBF) for 72 h by weight-loss method, as well as electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization measurements. Their surface morphology after immersion tests was observed by scanning electron microscopy (SEM). The results show that among the four alloys, AZ91D exhibits uniform corrosion with the lowest corrosion rate; AZ31 suffers serious pitting corrosion with the highest corrosion rate; while AM60 and ZK60 alloys exhibit similar corrosion behavior.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《腐蚀科学与防护技术》
Abstract: The synergistic inhibition effect of MoO42- and NO2- on pitting corrosion of mild steel was studied by polarization curve, electrochemical impedance spectroscopy (EIS), Mott-Schottky plot, and X-ray photoelectron spectroscopy (XPS). The results showed that the metastable pitting potential (Em) and the pitting breakdown potential (Eb) of the mild steel shift significantly to much positive and the value of (Eb-Em) increased markedly when MoO42- and NO2- were applied at the same time, indicating that the combined application of MoO42- and NO2- not only restrained the initiation of metastable pits but also prevented the transition from metastable pits to stable pits, correspondingly where a composite passive film Fe2O3+Fe2(MoO4)3 could form on the mild steel surface. The impedance of the composite passive film Fe2O3+Fe2(MoO4)3 formed in the solution containing MoO42- and NO2- was larger than that of the single passive films formed in the solutions with individual MoO42- or NO2-, while the defects of the former was less than that of the later one, therefore, the composite passive film could provide better protectiveness for the mild steel.