Application of mixed method for selection of corrosion resistant materials in acidic and saline environments. Aplicación de una metodología mixta para la selección de materiales resistentes a la corrosión en medios ácidos y salinos

Abstract

Objective: This article presents a mixed materials selection methodology is presented to determine which material has the best balance between corrosion resistance, mechanical properties and costs. Methods: The work was realized using potentiodynamic tests of extrapolation (Tafel) and electrochemical impedance (EIS), subjecting the samples to corrosive media of NaCl (3%) and H2SO4 (5%). The samples used were zirconia, steel AISI 304L, AISI 316 and AISI 316L. Finally a mixed methodology was applied in the materials selection to choose the material that has better comportment in this type of electrolyte. Results: For Tafel extrapolation test with 5% sulfuric acid (H2SO4) was obtained that AISI 316 steel which has the lowest current corrosion and passivation at higher power. In the electrolytic medium with 3 % NaCl, shows that higher values for corrosion potential present in stainless steels, showing a lower corrosion rate in the steels of the 316 series. Conclusions: The results showed that steel AISI 316 used presents the best performance to corrosion resistance in saline and acid.