Electrochemical Behavior of Steels Hastelloy C2000 and SAF 2205 Heat Treated and Inhibition Effect of SO42- Against their Corrosion in 1 M H3PO4

Amri, Afaf; Essahli, Mohamed; Lamsalmi, Moncef; Chtaini, Abdelilah; Hafid, Abderrafia; Ibnlfassi, Amina; Saad, El Madani

Electrochemical Behavior of Steels Hastelloy C2000 and SAF 2205 Heat Treated and Inhibition Effect of SO42- Against their Corrosion in 1 M H3PO4

Document Type : Original Article

Authors

Afaf Amri ¹^{, 2}

Mohamed Essahli ³

Moncef Lamsalmi ³

Abdelilah Chtaini ⁴

Abderrafia Hafid ⁴

Amina Ibnlfassi ¹

El Madani Saad ²

¹ Laboratory of Environmental Sciences and Development, University Hassan 1st, Faculty of Sciences and Technogies, Settat, Morocco

² Laboratory of Physical Chemistry of Process and Materials, University Hassan 1st, Faculty of Sciences and Technogies, Settat, Morocco

³ Laboratory of Applied Chemistry and Environment, University Hassan 1st, Faculty of Sciences and Technogies, Settat, Morocco

⁴ Laboratory of Molecular Electrochemistry and Inorganic Materials, University Sultan Moulay Slimane, Faculty of Sciences and Technogies, Béni Mellal, Morocco

Abstract

This work continues to focus on evaluating the electrochemical behavior of the steels Hastelloy C2000 and SAF 2205, after heat treatment in 700 °C and 900 °C in 1 M phosphoric acid. In addition, it reports on the effect of sulfate as a corrosion inhibitor of the two steels by using two electrochemical methods Tafel polarization and Electrochemical Impedance Spectroscopy (EIS). The electrochemical characterization of the two steels showed that the corrosion resistance decrease with the elevation of temperature from 700 °C to 900 °C in 1 M H3PO4. This decrease is about 76.21% for SAF 2205 and 19.37% for Hastelloy C2000. From these results, SAF 2205 is less resistant to corrosion than Hastelloy C2000 after heat treatment in acid environment. The comparison of the behavior of the two steels in the presence of sulfate showed that the corrosion current intensity of SAF 2205 is higher than that of the Hastelloy C2000. However, the separate analysis of each steel showed, an inhibitory efficiency of 99.99% with the addition of 0.1 g/l of SO42- for Hastelloy C2000 and about 91.06% for 0.2 g/l of SO42- for SAF 2205 as optimums concentrations.

Keywords

Hastelloy C2000, SAF 2205

Heat treatment

Corrosion inhibitor

Sulfate

Subjects