# Corrosion ## Microsim ### Live player <div class="microsim-player"> <iframe src="https://editor.p5js.org/sciencenibber/full/lzAm1zjcY" width="100%" height="620" frameborder="0" sandbox="allow-scripts allow-same-origin"></iframe> </div> <div class="microsim-fallback"> <img src="Microsims/thumbs/Corrosion.png" alt="Corrosion microsim poster" style="width:100%;border:1px solid #4445;border-radius:6px;"> <p><em>Live microsim (desktop) · <a href="https://editor.p5js.org/sciencenibber/sketches/lzAm1zjcY">open sketch in the p5.js editor</a></em></p> </div> **Editor URL:** https://editor.p5js.org/sciencenibber/sketches/lzAm1zjcY **Description (100 words):** A play-it-yourself corrosion cell. A steel piling sits in electrolyte while iron dissolves at an anodic pit (`Fe -> Fe2+ + 2e-`) and oxygen is reduced at cathodic sites; electrons stream up through the metal and `Fe2+` ions drift into solution. The Evans diagram on the right plots the anodic and cathodic Tafel branches, and their crossing fixes the corrosion potential `E_corr` and current `i_corr`, which Faraday's law turns into a live `mm/yr` rate. Drag salinity, temperature, and dissolved oxygen up and the rate climbs; deaerate the water or apply cathodic protection and the operating point slides down the anodic line until metal loss nearly stops. ← Back to [[Helium]] <!-- LOCAL-MEDIA-PASS:START --> ## Links (Wikipedia order) <!-- injected from _registry/childlinks/Corrosion.json (2026-07-30T02:09:12Z) --> `Achilles'_heel` · `Acidic_oxide` · [[Alloy]] · [[Aluminium]] · `Aluminium_alloy` · `Aluminium_oxide` · `Anaerobic_corrosion` · `Anode` · `Anodic_protection` · `Anodizing` · `Aqueous_solution` · `Bacterial_anaerobic_corrosion` · `Belay_device` · `Biogenic_sulfide_corrosion` · `Bolt_(fastener)` · `Boron_oxide` · `Borosilicate_glass` · `Bridge` · `Bubble_(physics)` · `Buckling` · [[Cadmium]] · `Calcium_oxide` · `Carbon_black` · `Carbon_dioxide` · `Carbon_monoxide` · `Carbonation` · `Carbonic_acid` · `Cast_iron` · `Cathode` · `Cathodic_protection` · `Cavitation` · `Ceramic` · `Chemical_bond` · `Chemical_industry` · `Chemical_kinetics` · `Chloride` · [[Chlorine]] · `Chromate_conversion_coating` · [[Chromium]] · `Compacted_oxide_layer_glaze` · `Concentration_cell` · `Concrete` · `Concrete_cover` · `Controlled_permeability_formwork` · `Corroded_(band)` · `Corrosion_(album)` · [[Corrosion_engineering]] · `Corrosion_fatigue` · `Corrosion_in_space` · `Corrosion_inhibitor` · `Creep_(deformation)` · `Crevice_corrosion` · `Crystallite` · `Cyclic_corrosion_testing` · `DNA` · `Deal–Grove_model` · `Depletion_region` · [[Diffusion]] · `Dimetcote` · `Direct_current` · `Duran_(glass)` · `Eifel_Aqueduct` · `Electrical_resistivity_measurement_of_concrete` · `Electrochemical_cell` · `Electrochemical_scanning_tunneling_microscope` · `Electrode_potential` · `Electrolyte` · [[Electron]] · `Electronegativity` · `Electropolishing` · [[Entropy]] · `Environmental_stress_fracture` · `Erosion` · `Extrinsic_semiconductor` · `Faraday_paradox_(electrochemistry)` · [[Fatigue_(material)]] · `Federal_Highway_Administration` · `Fibre-reinforced_plastic_tanks_and_vessels` · `Fluoride` · [[Forensic_engineering]] · `Fouling` · `Fracture` · `Frost` · `Galvanic_cell` · `Galvanic_corrosion` · `Galvanic_series` · `Galvanization` · `Getter` · `Glass_disease` · [[Gold]] · `Gold_nugget` · `Graphite` · `Gross_domestic_product` · `Hard_water` · `High-temperature_corrosion` · `Hot-dip_galvanization` · `Humidity` · `Hydrochloric_acid` · [[Hydrogen]] · `Hydrogen_analyzer` · `Hydrogen_embrittlement` · `Hydrogen_sulfide` · `Hydrolysis` · `Hydron` · `Hydronium` · `Impact_(mechanics)` · `Intergranular_corrosion` · `Ionizing_radiation` · [[Iron]] · `Iron_sulfate` · `Kelvin_probe_force_microscope` · `Liquid_metal_embrittlement` · `Litter` · [[Magnesium]] · `Marine_grade_stainless` · `Mechanical_overload` · [[Mercury_(element)]] · `Metal` · `Metal-induced_embrittlement` · `Metal_dusting` · `Mianus_River_Bridge` · `Microbial_corrosion` · `Microorganism` · `Natural_rubber` · `Neodymium_magnet` · [[Niobium]] · `Noble_metal` · `Nucleation` · `Oil_platform` · `Oxide` · `Oxidizing_agent` · [[Oxygen]] · `Ozone` · `Ozone_cracking` · `PH` · `Paint` · `Panel_edge_staining` · `Passivation_(chemistry)` · `Periodic_table` · `Phosphate` · `Phosphoric_acid` · `Pigment` · `Pitting_corrosion` · `Pitting_resistance_equivalent_number` · `Plastic_shopping_bag` · `Plasticizer` · `Plating` · [[Platinum]] · `Polyaniline` · `Polymer_degradation` · `Polyurethane` · `Polyvinyl_chloride` · `Pourbaix_diagram` · `Pyrex` · `Radical_(chemistry)` · `Rebar` · `Redox` · `Reduction_potential` · `Reinforced_concrete` · `Rivet` · `Rouging` · `SAE_304_stainless_steel` · `Salinity` · `Salt_(chemistry)` · `Salt_spray_test` · `Scanning_vibrating_electrode_technique` · `Seawater` · `Shrink_wrap` · [[Silicon]] · `Silver_Bridge` · `Soda–lime_glass` · `Sodium_oxide` · `Sodium_silicate` · `Solder` · `Spall` · `Stainless_steel` · [[Steel]] · `Stress_concentration` · `Stress_corrosion_cracking` · `Sulfidation` · `Sulfide_stress_cracking` · `Sulfuric_acid` · `Surface_states` · `Surfactant` · `Suspension_bridge` · `Temperature` · `Thermal_oxidation` · `Thermal_shock` · [[Thermodynamics]] · [[Titanium]] · `Titanium_dioxide` · `Tribocorrosion` · `Ultraviolet` · `Vitreous_enamel` · `Water_vapor` · [[Wayback_Machine]] · `Wear` · `Welding` · `West_Virginia` · `Yield_(engineering)` · [[Zinc]] ## From the vault media library !Corrosion thumb.png *Corrosion — from the vault's own media holdings, placed 2026-07-09. MTN / Wikitube.io original · CC BY-SA 4.0.* <!-- LOCAL-MEDIA-PASS:END --> > **Room:** [[Helium]] · **Status:** ✅ shipped ## Overview **Corrosion** is the electrochemical degradation of a metal as it reverts toward a lower-[[Energy|energy]] oxidized state, and on a [[Steel|steel]] surface in water it proceeds as two coupled half-reactions sharing the same piece of metal: an **anodic** reaction in which iron dissolves (`Fe -> Fe2+ + 2e-`) and a **cathodic** reaction that consumes the liberated electrons — in aerated neutral water this is oxygen reduction (`O2 + 2H2O + 4e- -> 4 OH-`). Because the two must proceed at equal rates, the metal floats to a **mixed corrosion potential** `E_corr` where the anodic and cathodic current densities are equal; that shared value, the **corrosion current** `i_corr`, sets the metal-loss rate through Faraday's law, `CR(mm/yr) = 3.27e-3 * i_corr * EW / rho`. Plotted as potential against the logarithm of current — an **Evans diagram** — Tafel kinetics render each half-reaction a straight line, while oxygen reduction bends to a vertical **[[Diffusion|diffusion]]-limited plateau** fixed by the dissolved-oxygen supply. The rate is therefore tunable: higher **salinity** (electrolyte conductivity), **temperature** (Arrhenius kinetics), and **dissolved oxygen** all push `i_corr` up, whereas removing oxygen (**deaeration**) or applying **cathodic protection** — polarizing the steel below `E_corr` so the anodic dissolution current collapses — push it down. This is why protection is engineered, not assumed: the same surface that rusts in months under warm aerated brine can be held nearly inert by a few hundred millivolts of impressed potential. **Helium connection:** the helium economy is built largely from carbon and stainless steel living in corrosive service — the coastal and offshore natural-gas wells and gathering lines (including those of the Babbitt, Minnesota helium field) that carry wet, sometimes sour gas before helium is ever separated, the pressure vessels and cryogenic-plant piping of liquefaction trains, and their seawater-cooled heat exchangers and buried lines — so the integrity and the cathodic-protection budget of that hardware are governed by exactly the electrochemical rate this microsim lets you tune. <!-- CRAFT-LINK:START g12 --> *Built to the [[WT!P5_js_Microsim_Master_Class|p5.js Master Class]].* <!-- CRAFT-LINK:END --> <!-- SPINEPATH:BEGIN g20 — shortest chain of Wikipedia links between local articles to a Compendium Main article; do not hand-edit inside --> *Connected to the Apex Spine:* Corrosion → [[Cavitation|Cavitation]] — [[WT!Thury_Hydrodynamics_Compendium|Compendium]] section 29, *Cavitation*. <!-- SPINEPATH:END --> <!-- MATTERSIM:BEGIN g33 — Matter & Energy Cluster microsim (framework build, specs/sims/Corrosion.json); do not hand-edit inside --> **Microsim — three.js (Wikitube framework):** *Corrosion* <div class="wt-sim" data-src="https://wikitube-3d-microsims.netlify.app/matter/Corrosion.html" data-title="Corrosion"></div> *Built from `MICROSIM_GUIDE/specs/sims/Corrosion.json`; part of the [[PORTAL_Matter|Matter portal]] spine (section sims and See-also variants).* <!-- MATTERSIM:END --> ## Wikipedia : Wikitube **Strict pair:** [Wikipedia](https://en.wikipedia.org/wiki/Corrosion) : [Wikitube](https://en.wikitube.io/wiki/Corrosion) ## Previous hub tags Tree parents: [[Oxygen]] · [[Reliability_engineering]]. Legacy hubs: none. --- *Sources: 1 legacy note. Minted wave 1, 2026-07-30 (v1.6 order).*