(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.

A metal that readily combines with oxygen at elevated temperatures to form very stable oxides, for example, titanium, zirconium, and beryllium. Reactive metals may also become embrittled by the interstitial absorption of oxygen, hydrogen, and nitrogen.

In tensile testing, the ratio of maximum load to original cross-sectional area. Also called ultimate tensile strength.

Current that flows through the earth from an anodic to a cathodic area of a continuous metallic structure. Usually used only where the areas are separated by considerable distance and where the current results from concentration-cell action.

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

The slope (dE/di) at the corrosion potential of a potential (E)/current density (i) curve. Also used to describe the method of measuring corrosion rates using this slope.

Deterioration of wood in contact with iron-based alloys.

The structure of a prepared surface of a metal as revealed by a microscope at a magnification exceeding 25x.

A compound that causes reduction, thereby itself becoming oxidized.

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.

The accelerated deterioration at the interface between contacting surfaces as the result of corrosion and slight oscillatory movement between the two surfaces; Deterioration at the interface between two contacting surfaces accelerated by relative motion b ...

Short, discontinuous internal fissures in wrought metals attributed to stresses produced by localized transformation and decreased solubility of hydrogen during cooling after hot working. In a fracture surface. flakes appear as bright silvery areas; on an ...

Pitting resulting from ablation, outgassing or meteor contact.

Spontaneous aging of a supersaturated solid solution at room temperature. See also aging. Compare with artificial aging.

A metallurgical term describing the formation of graphite in iron or steel, usually from decomposition of iron carbide at elevated temperatures. Not recommended as a term to describe graphitic corrosion.

A surface-active agent; usually an organic compound whose moleculei contain a hydrophilic group at one end and a lipophilic group at the other.

A hard, brittle, nonmagnetic intermediate phase with a tetragonal crystal structure, containing 30 atoms per unit cell, space group P42mnm, occurring in many binary and ternary alloys of the transition elements. The composition of this phase in the variou ...

Corrosion due to the action of "local cells," that is, galvanic cells resulting from inhomogeneities between adjacent areas on a metal surface exposed to an electrolyte.

Areas on a steel fracture surface having a characteristic white crystalline appearance.

Catastrophic brittle failure of a normally ductile metal when in contact with a liquid metal and subsequently stressed in tension.