(See related pages)
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| Corrosion | the deterioration of a material resulting from chemical attack by its environment. (See page(s) 721; Sec. 12.1) |
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| Anode | the metal electrode in an electrolytic cell that dissolves as ions and supplies electrons to the external circuit. (See page(s) 721; Sec. 12.2) |
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| Cathode | the metal electrode in an electrolytic cell that accepts electrons. (See page(s) 721; Sec. 12.2) |
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| Electromotive force series | an arrangement of metallic elements according to their standard electrochemical potentials. (See page(s) 721; Sec. 12.3) |
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| Galvanic cell | two dissimilar metals in electrical contact with an electrolyte. (See page(s) 721; Sec. 12.3) |
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| Ion-concentration cell | galvanic cell formed when two pieces of the same metal are electrically connected by an electrolyte but are in solutions of different ion concentrations. (See page(s) 721; Sec. 12.3) |
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| Oxygen-concentration cell | galvanic cell formed when two pieces of the same metal are electrically connected by an electrolyte but are in solutions of different oxygen concentration. (See page(s) 721; Sec. 12.3) |
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| Cathodic polarization | the slowing down or the stopping of cathodic reactions at a cathode of an electrochemical cell due to (1) a slow step in the reaction sequence at the metal-electrolyte interface (activation polarization) or (2) a shortage of reactant or accumulation of reaction products at the metal-electrolyte interface (concentration polarization). (See page(s) 721; Sec. 12.4) |
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| Passivation | the formation of a film of atoms or molecules on the surface of an anode so that corrosion is slowed down or stopped. (See page(s) 721; Sec. 12.4) |
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| Galvanic (seawater) series | an arrangement of metallic elements according to their electrochemical potentials in seawater with reference to a standard electrode. (See page(s) 721; Sec. 12.4) |
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| Pitting corrosion | local corrosion attack resulting from the formation of small anodes on a metal surface. (See page(s) 721; Sec. 12.5) |
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| Intergranular corrosion | preferential corrosion occurring at grain boundaries or at regions adjacent to the grain boundaries. (See page(s) 721; Sec. 12.5) |
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| Weld decay | corrosion attack at or adjacent to a weld as the result of galvanic action resulting from structural differences in the weld. (See page(s) 721; Sec. 12.5) |
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| Stress corrosion | preferential corrosive attack of a metal under stress in a corrosive environment. (See page(s) 721; Sec. 12.5) |
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| Selective leaching | the preferential removal of one element of a solid alloy by corrosion processes. (See page(s) 721; Sec. 12.5) |
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| Pilling-Bedworth (P.B.) ratio | the ratio of the volume of oxide formed to the volume of metal consumed by oxidation. (See page(s) 721; Sec. 12.6) |
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| Cathodic protection | the protection of a metal by connecting it to a sacrificial anode or by impressing a DC voltage to make it a cathode. (See page(s) 722; Sec. 12.7) |
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| Anodic protection | the protection of a metal that forms a passive film by the application of an externally impressed anodic current. (See page(s) 722; Sec. 12.7) |