Iron Pourbaix Diagram 2D: Corrosion, Immunity & Passivation

Every electrochemical corrosion problem comes down to two numbers: the electrode's potential and the solution's pH. This simulator draws a real potential-pH (Pourbaix) diagram for the iron-water system, with every boundary line derived on the fly from the Nernst equation and the solubility product of Fe(OH)₂ rather than hard-coded, and links it to a rotatable 2D cross-section of an iron electrode that actually dissolves into Fe²⁺ ions in the corrosion region, sits inert in the immunity region, and grows a protective oxide ring in the passivation region. Drag the diagram or the pH/potential sliders to explore why cathodic protection, alkaline treatment and passivating coatings all work by moving the operating point into a different region of the same diagram, and drag the electrode view itself to rotate it and watch the corrosion history strip below track the rate and film coverage over time.