The selective corrosion of one or more components of a solid solution alloy, usually in the form of ions. Also called parting or selective leaching. See also decarburization, decobaltification, denickelification, dezincification, and graphitic corrosion.

(1) Hardening suitable a = b alloys (most often certain copper or titanium alloys) by solution treating and quenching to develop a martensite-like structure. (2) In ferrous alloys, hardening by austenitizing and then cooling at a rate such that a substant ...

A treatment of metal in a solution of a hexavalent chromium compound to produce a conversion coating consisting of trivalent and hexavalent chromium compounds.

A strongly alkaline solution into which metal is immersed for etching. for neutralizing acid, or for removing organic materials such as greases or paints.

Provisional value for plane-strain fracture toughness.

The ability of a material to deform plastically without fracturing, measured by elongation or reduction of area in a tensile test, by height of cupping in an Erichsen test, or by other means.

A technique commonly used to prepare metallographic specimens, in which a high polish is produced by making the specimen the anode in an electrolytic cell, where preferential dissolution at high points smooths the surface.

The maximum anodic current density observed in the active region for a metal or alloy electrode that exhibits active-passive behavior in an environment.

Corrosion with gas as the only corrosive agent and without any aqueous phase on the surface of the metal. Also called dry corrosion.

Corrosion resulting from a cathodic condition of a structure usually caused by the reaction of an amphoteric metal with the alkaline products of electrolysis.

The minimum value of Kc for any given material and condition, which is attained when rapid crack propagation in the opening mode is governed by plane-strain conditions.

The maximum stress that can be sustained for a specified number of cycles without failure, the stress being completely reversed within each cycle unless otherwise staled.

An obsolete historical term denoting a form of stress-corrosion cracking most frequently encountered in carbon steels or iron-chromium-nickel alloys that are exposed to concentrated hydroxide solutions at temperatures of 200 to 250

Electrolytic pickling in which the work is the cathode.

The thermodynamic function 3G = 5H - TSS, where H is enthalpy, T is absolute temperature. and S is entropy. Also called free energy, free enthalpy, or Gibbs function.

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.

Plating with dummy cathodes.

Embrittlement of alloy steels caused by holding within or cooling slowly through a temperature range just below the transformation range. Embrittlement is the result of the segregation at grain boundaries of impurities such as arsenic, antimony, phosphoru ...

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.

An oil capable of conversion from a liquid to a solid by slow reaction with oxygen in the air.