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

Substance formed as a result of corrosion

(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.

Intergranular fracture of maraging steels with decreased toughness resulting from improper processing after hot working. Thermal embrittlement occurs upon heating above l095

A metal having an extremely high melting point, for example, tungsten, molybdenum, tantalum, niobium, chromium, vanadium, and rhenium. In the broad sense, this term refers to metals having melting points above the range for iron, cobalt, and nickel.

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

(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.

Deterioration of gray cast iron in which the metallic constituents are selectively leached or converted to corrosion products leaving the graphite intact. The term graphitization is commonly used to identify this form of corrosion, but is not recommended ...

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.

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

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

The wires, connectors, measuring devices, current sources, etc., that are used to bring about or measure the desired electrical conditions within the test cell. It is this portion of the cell through which electrons travel.

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.

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 ...

Deterioration of wood in contact with iron-based alloys.

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

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 ...

A narrow zone in a metal corresponding to the transition from one crystallographic orientation to another, thus separating one grain from another; the atoms in each grain are arranged in an orderly pattern; the irregular junction of two adjacent grains is ...

(1) An isothermal reversible reaction in which a solid solution is converted into two or more intimately mixed solids on cooling, the number of solids formed being the same as the number of components in the system. (2) An alloy having the composition ind ...

Pitting resulting from ablation, outgassing or meteor contact.