A powerfully oxidizing allotropic form of the element oxygen. The ozone molecule contains three atoms (O3). Ozone gas is decidedly blue, and both liquid and solid ozone are an opaque blue-black color, similar to that of ink.

A black finish on a metal produced by immersing it in hot oxidizing salts or salt solutions.

Electrode reaction equivalent to a transfer of negative charge from the electronic to the ionic conductor. A cathodic reaction is a reduction process. An example common in corrosion is: Ox + ne s Red.

Pitting corrosion resulting from deposits on a metal surface which cause concentration cells.

A pattern of parallel surface cracks that are formed by alternate rapid heating and cooling of the extreme surface metal, sometimes found on forging dies and piercing punches. There may be two sets of parallel cracks one set perpendicular to the other.

Pertaining to the body-centered cubic crystal structure (BCC) of many ferrous (iron-base) metals.

(1) A metal corroding under the control of a surface reaction product. (2) The state of the metal surface characterized by low corrosion rates in a potential region that is strongly oxidizing for the metal. (3) The state of a metal when its behavior is mu ...

The electroplating of zinc upon iron or steels

(1) A cell, the emf of which is due to the potential difference between a metal in an active state and the same metal in a passive state. (2) A corrosion cell in which the anode is a metal in the active state and the cathode is the same metal in the passi ...

Embrittlement of stainless steels upon extended exposure to temperatures between 400 and 510

A type of inhibitor that appreciably changes the potential of u metal to a more noble (positive) value.

The algebraic ratio of two specified stress values in a stress cycle. Two commonly used stress ratios are: (1) the ratio of the alternating stress amplitude to the mean stress. A = Sa/Sm and (2) the ratio of the minimum stress to the maximum stress. R =Sm ...

Cracking that occurs in the weld metal. See also cold cracking, hot cracking, lamellar tearing, and stress-relief cracking.

The electrolyte adjacent to the cathode of an electrolytic cell.

The ratio of the electric current density to the electric field in a material. Also called electrical conductivity or specific conductance.

See gaseous corrosion.

A measure of proportion by weight, equivalent to one unit weight of a material per billion (109) unit weights of compound. One part per billion is equivalent to 1 mg/kg.

An electrode commonly used in polarization studies to pass current to or from a test electrode, usually made of noncorroding material

The range of the stress-intensity factor during a fatigue cycle.

Localized corrosion of a metal surface at, or immediately adjacent to, an area that is shielded from full exposure to the environment because of close proximity between the metal and the surface of another material.