Behaviour of Ni and Ni oxide thin films obtained by different techniques for the prevention of corrosion in sour media

Abstract

Purpose

The purpose of this paper is to evaluate the use of nickel and nickel oxide thin films as anticorrosive protection for low‐carbon steel when expose to sour media. The purpose of this paper is also the study of a superior oxide nickel thin film over the nickel thin film.

Design/methodology/approach

Nickel thin films are applied on steel AISI 1018 (UNS G 10180) by magnetron sputtering and electrolytic techniques. The films are tested after deposition on low‐carbon steel. A massive nickel electrode also is evaluated as a reference. In order to evaluate the protective properties of films in sour media, electrochemical techniques are employed, but also scanning electron microscopy in order to identify the difference in porosity and surface of the films coated by both techniques.

Findings

Micrographs of thin films deposited by magnetron sputtering reveal a homogeneous surface whereas the electrolytic films show many micro‐crevices and expose the substrate even on the oxide films. These results indicate that localize corrosion on the film surface diminishes the corrosion resistance, even if the film itself has a superior corrosion resistance.

Practical implications

These kinds of nickel thin films deposit by magnetron sputtering and their oxides are an excellent anticorrosion alternative even for mild carbon steel exposed on sour media.

Originality/value

The sputtered nickel deposit is consistently more protective against corrosion than an electrolytic deposit of the same thickness. The nickel oxide benefits the steel by displacement of the corrosion potential towards more positive values. The electrochemical performance of solid nickel oxide is superior compared to the nickel metallic film on the steel substrate.

Citation

Magaña‐Zavala, C.R., Angeles‐San Martín, M.E. and Rodríguez‐Gómez, F.J. (2009), "Behaviour of Ni and Ni oxide thin films obtained by different techniques for the prevention of corrosion in sour media", Anti-Corrosion Methods and Materials, Vol. 56 No. 5, pp. 255-260. https://doi.org/10.1108/00035590910989543