The chemical or electrochemical reaction between a material, usually a metal, and its environment that produces a deterioration of the material and its properties.

Interfacial reaction equivalent to a transfer of charge between electronic and ionic conductors. See also anodic reaction and cathodic reaction.

One of the group of l5 chemically similar metals with atomic numbers 57 through 7l, commonly referred to as the lanthanides.

A measure of the acidity or alkalinity of a solution; The negative logarithm of the hydrogen-ion activity; it denotes the degree of acidity or basicity of a solution. At 25

Chromium plated for engineering rather than decorative applicactions.

A fracture, usually of' polycrystalline metal, in which most of the grains have failed by cleavage, resulting in bright reflecting facets. It is associated with low-energy brittle fracture.

See cathodic protection.

The maximum repeated stress that can he endured by a metal without failure under definite conditions of corrosion and fatigue and for a specific number of stress cycles and a specified period of time.

A list of metals and alloys arranged according to their relative corrosion potentials in a given environment. Compare with electromotive series.

(1) A molecular structure in which a heterocyclic ring can he formed by the unshared electrons of neighboring atoms. (2) A coordination compound in which a heterocyclic ring is formed by a metal bound to two atoms of the associated ligand. See also comple ...

An assembly, consisting of a vessel, electrodes, and an electrolyte, in which electrolysis can be carried out.

Corrosion which is increased because of the abrasive action of a moving stream; the presence of suspended particles greatly accelerates abrasive action.See erosion-corrosion.

See mixed potential.

The potential of a reversible oxidation-reduction electrode measured with respect to a reference electrode, corrected to the hydrogen electrode, in a given electrolyte.

Particles of foreign material in a metallic matrix. The particles are usually compounds (such as oxides, sulfides, or silicates), but may be of any substance that is foreign to (and essentially insoluble in) the matrix.

Modification of a corrosion system so that corrosion damage is mitigated.

Deterioration of metals as a result of the metabolic activity of microorganisms.

A chemical compound with one or more carboxyl radicals (COOH) in its structure; examples are butyric acid, CH3(CH2)2COOH; maleic acid, HOOCCH-CHCOOH; and benzoic acid, C6H5COOH.

An electrode immersed in a suitable electrolyte, designed for measurements of electrode potential; A pure metal in contact with a solution of known concentration of its own ion, at a specific temperature develops a potential which is characteristic and re ...

An equation that expresses the exact electromotive force of a cell in terms of the activities of products and reactants of the cell.