Direct current supplied by a device employing a power source external to the electrode system of a cathodic protection installation.

Corrosion that occurs under some coatings in the form of randomly distributed threadlike filaments.

Coal tar or asphalt-based coating.

(1) Producing a chromate conversion coating on magnesium for temporary protection or for a paint base. (2) The solution that produces the conversion coating.

Separation of a solid accompanied by little or no macroscopic plastic deformation. Typically, brittle fracture occurs by rapid crack propagation with less expenditure of energy than for ductile fracture.

Corrosion in which cobalt is selectively leached from cobalt-base alloys, such as Stellite

Foreign substance which comes from the environment, adhering to a surface of a material

Plating wherein fine metal powders are peened onto the work by tumbling or other means.

The maximum compressive stress a material is capable of developing. With a brittle material that fails in compression by fracturing, the compressive strength has a definite value. In the case of ductile, malleable, or semiviscous materials (which do not f ...

A change in any part of the corrosion system caused by corrosion.

Any of the elements of the halogen family, consisting of fluorine, chlorine, bromine, iodine, and astatine.

Aging induced by rapid cooling after solution heat treatment.

The net transfer of electric charge per unit time. Also called electric current. See also current density.

The maximum current density that can be used to obtain a desired electrode reaction without undue interference such as from polarization.

A cell in which chemical change is the source of electrical energy. It usually consists of two dissimilar conductors in contact with each other and with an electrolyte. or of two similar conductors in contact with each other and with dissimilar electrolyt ...

A state of resistance to corrosion or anodic dissolution of a metal caused by thermodynamic stability of the metal.

Heating a ferrous alloy to a suitable temperature above the transformation range and then cooling in air to a temperature substantially below the transformation range.

See inhibitor

The potential of a corroding surface in an electrolyte, relative to a reference electrode. Also called rest potential, open circuit potential, or freely corroding potential.

Rapid cooling of metals (often steels) from a suitable elevated temperature. This generally is accomplished by immersion in water, oil, polymer solution, or salt, although forced air is sometimes used.