Electro-deposition is an electrochemical method of metal film deposition on a solid surface contained an electrolyte [1], which was introduced by the Russian chemist Kistiakowsky in the early twentieth century [2]. This process is very used in industry for many types of applications [3, 4].

In this work, the nickel phosphorus coatings are elaborated on a steel substrate X52 by the electro-deposition method by varying the applied current and they are characterized by (X-ray diffraction, EDX and the micro-hardness) to study the corrosion phenomena.

The aim of this study is to find the optimal conditions that allow obtaining the better coatings that are more effective against the corrosion when they are submitted to an aggressive environment (3.5%NaCl). For this we use the technique of polarization as a method for characterization and evaluation of corrosion.

The results obtained by the stationary electrochemical method showed that the nickel phosphorus coating obtained at I = 0.10 presents a good corrosion resistance in the 3.5 % NaCl environment.