Glossary CorrosionRSS

Glossary Corrosion

Forming austenite by heating a ferrous alloy into the transformation range (partial austenitizing) or above the transformation range (complete austenitizing). When used without qualification, the term implies complete austenitizing.

In electroplating, a supplementary anode positioned so as to raise the current density on a certain area of the cathode and thus obtain better distribution of plating.

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

Material placed in a drilled hole to fill space around anodes, vent pipe, and buried components of a cathodic protection system.

A metastable aggregate of ferrite and cementite resulting from the transformation of austenite at temperatures below the pearlite range but above M

A segregated structure consisting of alternating nearly parallel bands of different composition, typically aligned in the direction of primary hot working.

A chemical substance that yields hydroxyl ions (OH ) when dissolved in water. Compare with acid.

(1) The metal present in the largest proportion in an alloy; brass, for example, is a copper-base alloy. (2) An active metal that readily oxidizes, or that dissolves to form ions. (3) The metal to be brazed, cut, soldered, or welded. (4) After welding, th ...

Macroscopic progression marks on a fatigue fracture or stress-corrosion cracking surface that indicate successive positions of the advancing crack front. The classic appearance is of irregular elliptical or semielliptical rings, radiating outward from one ...

See principal stress (normal).

(Galvanic Corrosion) Corrosion resulting from dissimilar metal contact.

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

An electrode in an electrolytic cell that is not mechanically connected to the power supply, but is so placed in the electrolyte, between the anode and cathode, that the part nearer the anode becomes cathodic and the part nearer the cathode becomes anodic ...

Coal tar or asphalt-based coating.

The liquid material remaining from pulpwood cooking in the soda or sulfate paper-making process.

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

A raised area, often dome shaped, resulting from (1) loss of adhesion between a coating or deposit and the base metal or (2) delamination under the pressure of expanding gas trapped in a metal in a near-subsurface zone. Very small blisters may be called p ...

(1) Injection of air or water under high pressure through a tube to the anode area for the purpose of purging the annular space and possibly correcting high resistance caused by gas blocking. (2) In connection with boilers or cooling towers, the process o ...

Brittleness exhibited by some steels after being heated to a temperature within the range of about 200 to 370

Whitening and loss of gloss of a usually organic coating caused by moisture. Also called blooming.