An obsolete historical term usually applied to stress-corrosion crackling of brass.

An electrolytic cell, the electromotive force of which is caused by a difference in concentration of some component in the electrolyte. This difference leads to the formation of discrete cathode and anode regions.

Localized corrosion frequently observed in oilwell tubing in which a circumfrential attack is observed near a region of metal "upset".

Introducing nitrogen into the surface layer of a solid ferrous alloy by holding at a suitable temperature (below Ac1 for ferritic steels) in contact with a nitrogenous material, usually ammonia or molten cyanide of appropriate composition. Quenching is no ...

A potential more cathodic (positive) than the standard hydrogen potential.

The electric current that flows between metals or conductive nonmetal in a galvanic couple.

A galvanic cell resulting from inhomogeneities between areas on a metal surface in an electrolyte. The inhomogeneities may be of physical or chemical nature in either the metal or its environment.

The force or load that produces elongation.

An alloy of lead containing 3 to l5% Sn, used as a hot dip coating for steel sheet or plate. Terne coatings, which are smooth and dull in appearance, give the steel better corrosion resistance and enhance its ability to be formed, soldered, or painted.

The maximum stress that a material can withstand for an infinitely large number of fatigue cycles. See also fatigue strength.

See embrittlement.

Any of several processes in which both nitrogen and carbon are absorbed into the surface layers of a ferrous material at temperatures below the lower critical temperature and, by diffusion, create a concenteration gradient. Nitrocarburizing is performed p ...

A metal which because of its relative position in the galvanic series, provides sacrificial protection to metals that are more noble in the series, when coupled in an electrolyte.

Forming an adherent phosphate coating on a metal by immersion in a suitable aqueous phosphate solution. Also called phosphatizing. See also conversion coating.

The formation of localized corrosion products scattered over the surface in the form of knoblike mounds called tubercles.

The ratio, expressed as a percentage, of the amount of water vapor present in a given volume of air at a given temperature to the amount required to saturate the air at that temperature.

A compound that causes reduction, thereby itself becoming oxidized.

(1) The formation at high temperatures of thick corrosion product layers on a metal surface. (2) The deposition of water-insoluble constituents on a metal surface.

A protective or decorative nonmetallic coating produced in silo by chemical reaction of a metal with a chosen environment. It is often used to prepare the surface prior to the application of an organic coating.

(1) Formation of a new, strain free grain structure from that existing in cold worked metal, usually accomplished by heating. (2) The change from one crystal structure to another, as occurs on heating or cooling through a critical temperature.