Avaliação da resistência à corrosão dos aços 1032 e 1035 em solução de água do mar sintética na presença de CO₂.

Abstract

Carbon steels represent one of the most widely used classes of engineering materials worldwide, standing out as essential components in offshore structures and in hydrocarbon exploration and transportation systems, especially due to their high economic efficiency. However, in marine environments, characterized by high salinity and the presence of CO₂, they are subject to intense corrosive processes that can seriously compromise structural integrity, making studies that seek to understand and mitigate such mechanisms indispensable. These steels have a carbon content that can reach approximately 1.5% and contain elements such as manganese (Mn), phosphorus (P), and sulfur (S), being classified as low (≤0.25%), medium (0.25–0.70%), and high carbon (0.70–1.05%) steels. Given this scenario, the present study aimed to evaluate the corrosion resistance of AISI 1032 and 1035 steels in a synthetic seawater solution, in accordance with ASTM D1141, subjected to carbon dioxide (CO₂) dissolution under simulated conditions typical of the offshore environment. To this end, electrochemical techniques were applied, including open circuit potential (OCP), linear polarization resistance (LPR), and electrochemical impedance spectroscopy (EIS), complemented by morphological analysis using optical microscopy. The results demonstrated that, although they present distinct microstructures, both materials exhibited similar corrosive performance, indicating that the microstructural differences did not significantly affect their corrosion behavior under the evaluated conditions.