CORROSION PROTECTION OF STEEL 1020 BY FILMS OF CONDUCTORS ELETRODEPOSITATED IN METHANOSULFONIC ACID

Alex Fernandes De Souza,Liu Yao Cho,Andrea Santos Liu

doi:10.30609/jeti.v1i1.5303

Abstract

1020 steel is widely used in the industrial sector, however it is a reactive metal and susceptible to corrosion, being necessary to use surface coatings to corrosion protect the metal in corrosive means. The polyaniline and polypyrrole are conductive polymers that have the ability to inhibit corrosion when deposited electrode in organic media. In this work, corrosion protection was investigated through polyaniline and polypyrrole films electrodeposited in methanesulfonic acid medium. The films were electrodeposited by chronoamperometry and the corrosion tests were performed by potentiodynamic polarization in aggressive sodium chloride medium. The surface of the films was analyzed by scanning electron microscopy. From the polarization it was observed that the polypyrrole film, in relation to the polyaniline film, showed better performance against corrosion. The MEV indicated that the polypyrrole film is homogeneous and adherent, while the polyaniline film showed flaws, allowing the interaction of the metal with the corrosive medium

Highlights

Steel is a metal widely used in the industrial sector, mainly made up of iron and carbon
The electrodeposition of PPy and PAni films were performed by chronoamperometry applying the potential of 1.2 V vs Ag / AgCl, established from the voltammogram of pyrrole, for 30 minutes that completely covered the working electrodes, resulting in the formation of both black and homogeneous films for polypyrrole and polyaniline
The PAni presented current values of approximately 0.033 A.cm-2, while PPy remained in the current range of approximately 0.005 A.cm-2

Summary

1- Introduction

Steel is a metal widely used in the industrial sector, mainly made up of iron and carbon. Research groups seek an alternative to the phosphating processes and the use of Cr +6, presenting as substitutes the conducting polymers [3] Conductive polymers, such as polypyrrole (PPy) and polyaniline (PAni), have a wide range of applications in their doped or partially oxidized state, and present interesting results in the corrosion protection effect of steel [4]. These polymers are electrically conductive and may be called active coatings, as chemical or electrochemical interactions may occur with active metals [5].

3- Results and Discussion

4- Conclusions

5- References