Usually refers to quenching or rapid cooling at the die, where large volumes of forced air, water or a combination thereof are directed against aluminum extruded sections as they emerge from the die.

Controlled rapid cooling of a metal from an elevated temperature by contact with a liquid, a gas, or a solid.

Abbreviation for Rigid Container Sheet.

The method of locating the apertures in a die so that the major axis of each profile lies along a circle of defined radius, giving each portion of bearing surface the same relationship to the center of the die as similar portions on other profiles.

The press component which applies force against the dummy block. Ram and stem are interchangeable terms describing any extension of the main cylinder in an extrusion press.

A mechanical device which moves an applicator along a determined path repeatedly.

The amount of saleable aluminum in the form of extrusions obtained from a press run. The recovery ratio is the proportion of such saleable metal to either the original ingot or to the ready-to-extrude billet, as the case may be.

In metallurgy, the electrochemical process by which purified alumina (aluminum oxide) is broken down into its constituents, freeing metallic aluminum.

The comparison of the cross-sectional billet area to total cross-sectional area of the resulting extrusions. This is determined by the cross-sectional area of the container or upset billet divided by the cross-sectional area of the combined die openings.

Aluminum of very high purity (99.950 percent or higher) obtained by special metallurgical treatments.

The ability of a surface to reflect light and other electromagnetic radiation. Aluminum has high reflectivity: 80% or more for visible light, and 90% or more for infrared radiation.

Sheet suitable for the manufacture of reflectors.

Heating metal again to hot-working temperature. In general no structural changes are intended.

Aperture or opening in a die where its entrance is smaller than the exit.

Oil put on the sheet after cleaning and before coiling for shipment to prevent water stain.

A semi-finished rolled product of rectangular cross section is coil formed suitable for further rolling.

Those stresses set up within a metal as the result of non-uniform plastic deformation which may be caused by drastic temperature gradients in quenching.

The ability of a material to regain its original shape after distortion. Aluminum is a resilient material.

The smallest unit of measure that an instrument is capable of accurately and repeatedly indicating.

A bulge or hump in the die's metal flow area serving as a means of controlling the flow or feed of metal.

An elongated projection on a shape, forging or casting to provide stiffening.

A cylindrical sleeve that holds the die and backer in axial relationship to each other.

(1) To connect two or more pieces of material by inserting in a hole through them a metal pin with a head on one end of it, and then forming a second head on the other end; (2) The connecting pin itself.

See Hardness, Rockwell.

A solid wrought product, long in relation to its cross-section, which is not less than 0.375 inch in diameter. (Smaller sizes are classified as wire.)

Rod having on its surface a metallurgically bonded aluminum or aluminum alloy coating that is anodic to the core alloy to which it is bonded, thus electrolytically protecting the core alloy against corrosion.

Rod brought to final dimensions by cold working to obtain improved surface finish and dimensional tolerances.

Rod produced by cold working extruded rod.

Rod produced by cold working rolled rod.

Rod of a quality suitable for use in the manufacture of cold-headed products such as rivets and bolts.

Rod produced by hot extruding.

Rod produced by hot rolling.

The length of extrusion rod from each billet.

The uniform ground finish on the work rolls which is imparted to the sheet or plate during rolling.

An extraneous chip or particle of metal rolled into the surface of the

A rectangular semi-finished product, produced by hot rolling fabricating ingot and suitable for further rolling.

Coiled of flat sheet in specific tempers, widths, and thicknesses suitable for the manufacture of corrugated or V-crimp roofing.

A rope-like appearance in the rolling direction after the metal has undergone severe deformation.

This term is not recommended. The term Ovality is preferred.

A surface area showing a scratch or abrasion resulting from contact of the hot extrusion with the press equipment or tooling or, in the case of multi-hole dies, with others sections as they exit the press.

A consecutive number of points consistently increasing or decreasing, or above or below the central line. Can be evidence of the existence of special causes of variation.

Table at immediate exit of press leadout equipment which helps to guide and support the extrusion.

Downward flow of a paint film as a result of its being applied too heavily or too wet. Also called Runs.

Corrosion test using salt sprayed as a mist in a heated humidity chamber to simulate seashore conditions, or to accelerate corrosion at a controlled rate.

The simultaneous extrusion of two layers of metal failing to weld because of film impurities between them.

Mechanical removal of the surface layer from a fabricating ingot or semi-finished wrought product so that surface imperfections will not be worked into the finished product.

(1) For rolled products, a sharp indentation in the surface usually caused by a machine or during handling. (2) For extrusions, a synonym for handling mark. See Mark, Handling.

A scratch occurring during the fabricating process and subsequently drawn over, making it relatively smooth to the touch.

A scratch caused by relative motion between two contacting surfaces.

A more severe form of rub mark. See Mark, Rub.

An indentation which is straight, is in the rolling direction and is caused by contact with a sharp projection on equipment.

Minor indentations at an angle to the rolling direction that result

A scratch which is caused by moving contact of coating against a non-moving object in an oven.

A scratch which is subsequently rolled. It will then appear as a grayish white ladder (distinct transverse lines within the longitudinal indentation).

A short longitudinal indentation parallel to the rolling direction.

A provision on some extrusion presses for moving the die in a horizontal plane with respect to the container.

The part of the die or mandrel bearing used to make screw holes in the extrusion.

The pressure which locks the container and die face during the extrusion cycle.

The junction line of metal that has passed through a hollow die, separated and rejoined at the exit point. Seams are present in all extruded hollows produced from the extrusion process and in many cases are not visible.

An unbonded fold or lap on the surface of the metal, which appears as a crack, usually the result of a defect in casting or working that has not bonded shut.

See Seam, Weld.

The junction line of metal that has passed through a hollow die, separated and rejoined at the exit point. Seams are present in all extruded hollows produced from the direct extrusion process and in many cases are not visible.

A hollow product which does not contain any line junctures resulting from method of manufacture.

Aluminum recovered primarily from scrap, segregated by alloy, and resmelted. Aluminum scrap is widely recycled and supports a large secondary aluminum production industry.

(1) A drawing showing an imaginary view through an item as though it had been cut by a plane (2) To cut through a piece of metal to expose an internal area for metallurgical examination.

The number assigned to an extruded or drawn profile for identification and cataloging purposes, usually the same number assigned for the same purpose to the die from which the profile is made.

An engineering drawing depicting the extrusion profile's cross-section.

A hardened screw with a sharp point, so designed that its threads cut their own mating threads when inserted and rotated in an appropriately-sized hole.

An extruded profile, any part of whose cross section partially encloses a void, the area of which is substantially greater than the square of the width of the gap.

Surface discoloration.

A bridge die that is recessed in a ring so that the butt can be sheared without any die stripping.

The device which separates or removes the extrusion residue or discard (billet butt) at the end of each cycle.

The leading (entry side) edge of a mandrel or die cap bearing.

A condition where the mandrel shear edge is offset from the die cap bearing edge.

The maximum stress that a material is capable of sustaining in shear. In practice, shear strength is considered to be the maximum average stress computed by dividing the ultimate load in the plane of shear by the original area subject to shear. Shear strength is usually determined by inserting a cylindrical specimen through round holes in three hardened steel blocks, the center of which is pulled (or pushed) between the other two so as to shear the specimen on two planes. The maximum load divided by the combined cross-sectional area of the two planes is the shear strength.

A rolled product that is rectangular in cross section with thickness less than 0.250 inch but not less than 0.006 inch and with slit, sheared or sawed edges.

See Reroll, Stock.

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

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

Composite sheet having on both surfaces (if on one side only, Clad One Side Sheet) a metallurgically bonded metal coating, the composition of which may or may not be the same as that of the core.

Sheet in coils with slit edges.

Circles cut from coiled sheet.

Sheet cut to specified length from coils and which has a lesser degree of flatness than flat sheet.

Sheet with sheared, slit, or sawed edges, which has been flattened or leveled.

Circles cut from flat sheet.

Sheet having a non-uniform finish that may vary from sheet to sheet and within a sheet, and may not be entirely free from stains or oil.

Sheet having a moderate degree of brightness on one side and a mill finish on the other.

Sheet, one or both sides of which has a factory-applied paint coating of controlled thickness.

Sheet having a uniform bright finish on one side and a mill finish on the other.

Sheet having a uniform bright finish on both sides.

Uneven walls caused by core (mandrel) movement.

A condition in an extrusion die where a very slight chamfer is created on the edge formed by the bearing surface and die face which is much shorter than regular choke. This tends to slow metal flow.

For plate, sheet and forgings, the direction through the thickness perpendicular to both longitudinal and long transverse directions.

Contraction that occurs when metal cools from the hot-working temperature.

A semihollow die where the die plate (cap) and the mandrel overlap each other at or near the tongue. The interior profile surface is formed by the mandrel and the outside surface by the die cap. The two tooling components mate together with an overlapping condition to crate the semihollow profile.

A difference in thickness between the two edges of plate, sheet or foil.

A nonsymmetric distribution is said to be skewed.

An area of uncoated sheet which is frequently caused by equipment malfunction.

A residual buildup of aluminum alloy from preceding billets that adhere to the container liner wall. The thickness is determined by difference in container I.D. and circumference of dummy block. See Cleanout Block.

A joint assembled by sliding two mating parts together in the direction of their length.

Thin fragment of aluminum which is part of the material but only partially attached. Surface damage or residual liquation which is subsequently rolled are typical causes.

A metal blank for forging or impacting.

To fuse or melt ore, to extract or refine the metal it contains.

A dark film of debris, sometimes covering large areas, deposited on the sheet during rolling.

A series of reversing lateral bows in coil products. This condition is caused by a weaving action during an unwinding or rewinding operation.

A self-locking joint whose mating parts exert a cam action, flexing until one part slips past a raised lip on the other part, preventing their separation.

A mark or blemish left on the surface of the extrusion caused by any sudden die or extrusion tooling movement.

In metallurgy: the prolonged heating period during several methods of heat treating metals, soaking allows the heat to penetrate completely the mass of metal, and so permits the required metallurgical changes to take place.

A general term loosely describing most alloys of the 1xxx, 3xxx, or 6xxx series.

Joining metals by flowing a molten filler metal between the connecting surfaces at a melting range below an arbitrary temperature, usually about 800ºF. (At higher temperatures, the process is call brazing.) The filler metal, called solder, may have any of a variety of compositions formulated for the different metals to be joined; the so-called soft, or low-melting, solders are primarily of tin and lead.

A steel disk with one or more orifices or apertures of the same cross-sectional area and contour as the desired product, through which metal is forced. Such dies are generally employed where profiles other than hollow are required. If solid dies are used for hollow profiles (as opposed to the use of hollow dies of the bridge, porthole or spider type containing a fixed stub mandrel as an integral part of the die) then a mandrel actuated by the action of the ram must be employed. These may be fixed or floating mandrels which require hollow (cast or bored) billets. An exception is the piercing type mandrel, which needs no cored billet.

Any profile other than a hollow or semihollow.

Heating an alloy at a suitable temperature for sufficient time to allow soluble constituents to enter into solid solution where they are retained in a supersaturated state after quenching.

Blistering caused by entrapped solvent during baking, possibly caused by short flashoff or improper solvent balance.

The ability of cured paint film to resist attack by a particular solvent. Often used as an indication of cure.

The engineering requirement for judging acceptability of a particular characteristic. A specification is never to be confused with a control limit.

That portion of a sample taken for evaluation of some specific characteristic or property.

Is a reduction in the effective bearing length and is the opposite correction technique to choke. See Relieved, Back Taper.

A series of surface cracks perpendicular to the extruding direction. Speed tearing normally occurs in corner radii or extremities of a section and is caused by localized high temperature.

An extrusion die for producing hollow shapes, whose mandrel is supported by multiple legs attached to the cap. Metal flows between the spider's legs and reunites before emerging through the die aperture.

The end joint uniting two webs.

A non-uniform extraneous deposit of lube on the coated sheet.

An auxiliary tool sometimes attached to the end of the container to produce an effective billet of greater size than the I.D. of the container. Use of a spreader permits the extruding of sections considerably wider than container I.D., but only under definitely limited operating conditions.

A bearing surface exactly perpendicular to the die face and ideally to the metal flow.

(1) The measure of a bearing being perpendicular to the die face which can be accomplished with a toolmaker's square or equivalent techniques. (2) Characteristic of having adjacent sides or planes meeting at 90 degrees.

A low temperature thermal treatment designed to prevent age-softening in certain strain hardened alloys containing magnesium.

A discoloration due to non-uniform oxidation of the metal surface during heat treatment.

Surface discoloration which may vary from dark brown to white and is produced during thermal treatment by incomplete evaporation and/or oxidation of lubricants on the surface.

A yellow to brown area of surface discoloration at the ends of the extruded length. It is the residue of certain types of saw lubricants if they are not removed from the metal prior to the thermal treatment.

See Corrosion, Water Stain.

An established dimensional tolerance for a certain class of product.

Aluminum extrusions are produced to standard dimensional tolerances, unless otherwise specified.

Non-uniform coating application which results in absence of coating in certain areas.

Light walls on the extruded profile caused by a restricted flow of metal before the bearing entry.

An extrusion having one or more abrupt changes in cross section at intervals in its length.

A process similar to the conventional extrusion process producing an extrusion with abrupt changes in dimension. In this process the extrusion press is stopped when the billet is only partially extruded, the split dies are removed and replaced with dies of larger opening or orifice. Extrusion is then resumed. The result is an extrusion which has an abrupt change in cross section. The first portion extruded having the smaller cross section is called the minor section while the second portion having the larger cross section is called the major section.

Adherence of foil surfaces sufficient to interfere with the normal ease of unwinding.

The absence of divergence from a right (straight) line in the direction of measurement.

A measure of the change in size or shape of a body under stress, referred to its original size or shape. Tensile or compressive strain is the change, due to force, per unity of length in an original linear dimension in the direction of the force. It is usually measured as the change (in inches) per inch of length.

Modification of a metal structure by cold working, resulting in an increase in strength and hardness with loss of ductility.

A superficial band or elongated mark which produces a non-uniform surface appearance. A streak is often described by source.

A longitudinal discoloration that can occur where there are large changes in wall thickness as a result of uneven cooling. These streaks usually appear lighter than the surrounding metal.

A bright superficial band or elongated mark which produces a non-uniform surface appearance.

A dull continuous streak caused by smudge buildup on a buff used at shearing or other operations.

A bright region on the sheet caused by excessive roll surface wear.

A banded condition caused by non-uniform adherence of roll coating to a work roll. It can be created during hot and/or cold rolling. If generated in the hot rolling process, it is also called Hot Mill Pick-up.

Surface discoloration which may vary from gray to brown and found only on Alclad products.

Surface discoloration which may vary from gray to black, is parallel to the direction of rolling, and contains rolled in foreign debris. It is usually extraneous material from an overhead location that drops onto the rolling surface and is shallow enough to be removed by etching or buffing.

A narrow discontinuous streak caused by rolling over an area containing grossly excessive lubricant drippage.

A streak with a helical pattern appearance transferred to a rolled product from a work roll.

Milky colored band(s) parallel to the rolling direction which vary in both width and exact location along the length.

Elongated alternately bright and dull chevron markings.

A streak on the sheet surface in the rolling direction caused by transfer from the leveler rolls.

A non-uniform surface appearance parallel to the rolling direction.

A non-uniform appearance on an etched or anodized surface caused by heterogeneities (variabilities) remaining in the metal from the casting, thermal processes or hot working stages of fabrication.

The relationship between the structural strength of a material and its weight. the strength-to-weight ratio of structural aluminum alloys is about twice that of mild steel.

Force per unit of area. Stress is normally calculated on the basis of the original cross-sectional dimensions. The three kinds of stresses are tensile, compressive, and shear.

The reduction of the effects of internal residual stresses by thermal or mechanical means.

The process of stretching extruded sections beyond the yield strength of the alloy to achieve longitudinal straightness.

A process of removing bow and warpage where an extrusion is gripped between jaws and subjected to a stress higher than its yield strength and is elongated a definite amount to establish a permanent set.

In extrusion: straightening an aluminum member by pulling. An average stretch increases the length by about one-half of one percent, and produces correspondingly a slight decrease in the cross-sectional dimensions, called stretch-down.

Longitudinal non-uniform coating thickness caused by uneven application of the liquid coating.

A structural finish is a standard finish where surface imperfections are acceptable and appearance is not a requirement. This finish could be characterized by the term non-exposed.

An aluminum section, now usually extruded, of any design accepted as standard by the structural industry. Such shapes include I-beams, wide flange or H-beams, channels, angles, tees and zees.

A hardened alloy steel disk often employed when the bolster does not fill the die stack. See Bolster.

The Layer below the paint; that is, the substance being painted.

A defect caused when one face of a forging is sucked in to fill a projection on the opposite side.

Minute surface cracks on rolled products which can be caused by insufficient ingot scalping.

A document used to extract opinions or other information from a person or group of persons.