The aim of this work is to study the effect of chloride ions in the performance of LDX 2003 alloy and to characterize the interface formed in simulated concrete and simulated concrete-pore solutions. In order to have a baseline for analyzing LDX 2003 performance, this alloy is compared with two commonly used materials, AISI 1008 and SAE 316L. Electrochemical techniques such as potentiodynamic scan and electrochemical impedance spectroscopy are used to analyze the qualitative characteristics of the passive layer in four different chloride concentrations for the simulated concrete solutions: 0, 0.05, 0.7, and 3.5 wt%; and four different ratios of [Cl-]/[OH-] for the simulated concrete-pore solution: 0, 0.1, 1.0, and 10. For long-term experimental condition, equivalent circuits analogs were applied and the results were analyzed to describe and quantify meaningful parameters for corrosion performance. The electrochemical techniques are complemented by high resolution techniques, such as scanning electron microscopy, atomic force microscopy, and 3D optical microscopy.