Abrasion

The process of rubbing, grinding, or wearing away by friction.

Abrasive

A substance capable of grinding away another material.

The changing of the passive surface of a metal to a chemically active state. Contrast with passivation.

Precipitation from solid solution resulting in a change in properties of an alloy, usually occurring at room temperature (natural aging), or at elevated temperature (artificial aging).

Cooling of the heated metal, intermediate in rapidity between slow furnace cooling and quenching, in which the metal is permitted to stand in the open air.

Composite sheet produced by bonding either corrosion-resistant aluminum alloy or aluminum of high purity to base metal of structurally stronger aluminum alloy. The coatings are anodic to the core so they protect exposed areas of the core electrolytically during exposure to corrosive environment.

Composite plate comprised of an aluminum alloy core having both surfaces (if on one surface only, Alclad One Side Plate) a metallurgically bonded aluminum or aluminum alloy coating that is anodic to the core, thus electrolytically protecting the core against corrosion.

Alodizing

A proprietary term that applies to the application of an Amchem Products solution known as Alodine-merely one of several types of conversion coatings. Alodizing is included here because it is often confused with a very different process--ANODIZING.

Alligatoring

An internal crack or separation aligned parallel to the direction of major metal flow and, in the case of plate, sheet or foil, parallel to the rolled surfaces. In extrusions, it can be caused by contaminants that feed into the metal flow before it reaches the die opening or cracked billets.

Alloy

A substance having metallic properties and composed of two or more chemical elements of which at least one is a metal.

Alloying Element

An element added to a metal, and remaining in the metal, that effects changes in structure and properties.

Aluminizing

Forming an aluminum or aluminum alloy coating on a metal by hot dipping, hot spraying, or diffusion.

(Chemical symbol Al)

Element No. 13 of the periodic system; Atomic weight 26.97; silvery white metal of valence 3; melting point 1220 (degrees) F; boiling point approximately 4118 (degrees) F.; ductile and malleable; stable against normal atmospheric corrosion, but attacked by both acids and alkalis. Aluminum is used extensively in articles requiring lightness, corrosion resistance, electrical conductivity, etc. Its principal functions as an alloy in steel making; (1) Deoxidizes efficiently. (2) Restricts grain growth (by forming dispersed oxides or nitrides) (3) Alloying element in nitriding steel.

AMS

Abbreviation for Aerospace Material Specification.

Angulation

The deliberate departure from a horizontal passline on the entry side of a rolling mill used for one-side bright rolling.

Anisotropy

The characteristics of exhibiting different values of a property in different directions with respect to a fixed reference system in the material.

Annealing

Heating to and holding at a suitable temperature and then cooling at a suitable rate, for such purposes as reducing hardness, improving machinability, facilitating cold working, producing a desired microstructure, or obtaining desired mechanical, physical, or other properties. When applied to nonferrous alloys, the term annealing implies a heat treatment designed to soften an age-hardened alloy by causing a nearly complete precipitation of the second phase in relatively coarse form. Any process of annealing will usually reduce stresses, but if the treatment is applied for the sole purpose of such relief, it should be designated stress relieving.

Annealing Partial

Thermal treatment (-H2X temper nomenclature) given cold worked metal to reduce strength and increase ductility to controlled levels other than annealed temper.

(Aluminum Adic Oxide Coating)

A process of coating aluminum by anodic treatment resulting in a thin film of aluminum oxide of extreme hardness. A wide variety of dye colored coatings are possible by impregnation in process.

Anodizing Sheet

Sheet with metallurgical characteristics and surface quality suitable for the development of protective and decorative films by anodic oxidation processes.

ANSI

Abbreviation of American National Standards Institute.

Arbor Break

Bend, crease, wrinkle, or departure from flat, occurring perpendicular to the slit edge of a coil and which are repetitive in nature, with severity decreasing as the distance increases in the coil from the original source. Normally, it is found on the ID of a coil but can appear on the coil OD as a result of a prior winding operation.

Artifact

In microscopy, a false structure introduced during preparation of a specimen.

Artificial Aging

An aging treatment above room temperature.

ASME

Abbreviation for American Society of Mechanical Engineers.

ASTM

Abbreviation for American Society For Testing Material. An organization for issuing standard specifications on materials, including metals and alloys.

AWS

Abbreviation for American Welding Society.