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This non-galvanic form of corrosion can occur when a metal is subjected to a hot atmosphere containing oxygen, sulfur ("sulfidation"), or other compounds capable of oxidizing (or assisting the oxidation of) the material concerned. For example, materials used in aerospace, power generation, and even in car engines must resist sustained periods ...
In other cases, such as mixed metals in piping (for example, copper, cast iron and other cast metals), galvanic corrosion will contribute to accelerated corrosion of parts of the system. Corrosion inhibitors such as sodium nitrite or sodium molybdate can be injected into these systems to reduce the galvanic potential. However, the application ...
The vast majority of corrosion resistant metals and alloys used in engineering (stainless steels, titanium, aluminium etc.) fall into this category. These metals are thermodynamically unstable in the presence of oxygen or water, and they derive their corrosion resistance from the presence at the surface of a thin oxide film, called the passive ...
Depending on the environment developed in the crevice and the nature of the metal, the crevice corrosion can take a form of: pitting (i.e., formation of pits), but note pitting and crevice corrosion are not the same phenomenon, [8] filiform corrosion (this type of crevice corrosion that may occur on a metallic surface underneath an organic ...
Pitting corrosion, or pitting, is a form of extremely localized corrosion that leads to the random creation of small holes in metal. The driving power for pitting corrosion is the depassivation of a small area, which becomes anodic (oxidation reaction) while an unknown but potentially vast area becomes cathodic (reduction reaction), leading to ...
For example, using an epoxy coating on the interior surface of a pipeline can reduce the likelihood of SCC. [7] Cathodic Protection: Cathodic protection is a technique used to protect metals from corrosion by applying a small electrical current to the metal surface.
High-temperature corrosion is a mechanism of corrosion that takes place when gas turbines, diesel engines, furnaces or other machinery come in contact with hot gas containing certain contaminants. Fuel sometimes contains vanadium compounds or sulfates, which can form low melting point compounds during combustion.
Erosion corrosion is a form of corrosion damage usually on a metal surface caused by turbulence of a liquid or solid containing liquid and the metal surface. [67] Aluminum can be particularly susceptible due to the fact that the aluminum oxide layer which affords corrosion protection to the underlying metal is eroded away. [68] [69]