Commercial Forms of Aluminum Alloys: Part Two


Abstract:
Wrought product of aluminum alloys are divided in several groups on the bases of it form of production, usability and sizes.
Aluminum alloy sheet and plate are available in very large sizes. These large sizes are not furnished in all alloys, tempers, and finishes and cannot be procured from all suppliers. Generally, however, sheet and plate sizes obtainable in aluminum alloy exceed those available in other nonferrous metals and approximate those produced in steel.
Commercial aluminum foil ranges in thickness from 0.00017 to 0.0059 in. and in width from 0.250 to 61 in. It is produced with two sides bright or one side bright and one satin finished.

Sheet and Plate

Aluminum that is 0.250 in (6.35 mm) or thicker is classified as plate; sheet is 0.006 to 0.249 in. thick. Sheet is supplied either flat rolled or in coils. Sheet and plate are also available in circular and odd-shaped blanks that are sheared, blanked, sawed, or routed to size or specified configuration.

Aluminum alloy sheet and plate are available in very large sizes. These large sizes are not furnished in all alloys, tempers, and finishes and cannot be procured from all suppliers. Generally, however, sheet and plate sizes obtainable in aluminum alloy exceed those available in other nonferrous metals and approximate those produced in steel. Tolerances are about the same as those in other metals.

Alloys used in the production of sheet and plate can be divided into non-heat-treatable and heat treatable.

The standard non-heat-treatable alloys in which sheet and plate are supplied are EC metal, 1060, 1100, 3003, alclad 3003 3004, alclad 3004, 3105, 5005, 5050, 5052, 5082, 5083, 5086 5154, 5252, 5254, 5257, 5357, 5454, 5456, 5457, 5557, 5652 5657,6011, and 8280.

The standard heat treatable alloys regularly supplied as sheet and plate are: 2014, alclad 2014, 2024, alclad 2024,2219, alclad 2219,6061, alclad 6061, 6070, X7005, 7039, 7075, alclad 7075 7079, alclad 7079, 7139, 7178 and alclad 7178.

Protective Coatings. Interleaving paper is often used in shipping sheet and plate products. Standard interleaving is an anti-tarnish, non-corrosive kraft paper.

Oiling is employed as an alternate method to protect sheet and plate.

Gummed protective tape is sometimes applied to flat sheet and plate as surface protection during transit and subsequent handling.

A transparent vinyl strippable coating, applied during mill fabrication, affords a practical finish protection for a number of sheet products in transit and during plant handling and fabricating operations.

Specialty Products

Many special grades of sheet and plate are supplied to meet the requirements of specific applications.

Anodizing Sheet. For the application of protective and decorative coatings by the anodizing process.

Prepainted Sheet. A baked synthetic resin enamel finish is applied to one or both sides over a chemical conversion coating.

Reflector Sheet. For use in the manufacture of reflectors.

Lighting Sheet. Reflector sheet (either diffuse or specular) is prefinished for use in trough-type reflectors and other reflector applications where severe forming is not required.

Recording Sheet Circles. Used by the recording industry to produce master-copy recordings and high-quality transcription records, and for data recording and storage in memory units.

Brazing Sheet. Nonclad or special clad sheet for brazing purposes. Clad brazing sheet is coated on one or both surfaces with an alloy having a distinctly lower melting point than the parent or core alloy. The unclad product is furnished in alloys having a low melting temperature. It is used in furnace brazing applications as an alternative to a brazing alloy cladding and has the same function.

Litho Sheet. One side has optimum freedom from surface imperfections; supplied with a maximum degree of flatness, for use as a plate in offset printing.

Patterned Sheet. Raised or indented pattern on one or both surfaces affords a broad range of designs and textures for decorative purposes; available in both coiled and flat sheet forms.

Vinyl-Coated Sheet. Permanently bonded laminate of aluminum sheet and vinyl film.

Porcelain Enameling Sheet. Specifically designed to provide maximum porcelain enamel adherence.

Trailer Roof Sheet. Wide, relatively light-gage 3003 or 5052 alloy sheet used by the truck-trailer industry for one-piece roofs.

Rural Roofing Sheet. Standard sizes of formed or corrugated sheet for roofing or siding on farm and light commercial buildings. Usually pattern is embossed.

Decorative Panel Sheet. Standard sizes of embossed-and-formed 0.0215-in. sheet with trapezoidal corrugations. Prepainted in many different colors, for industrial and residential building applications.

Industrial Roofing Sheet. Standard sizes of formed sheet, plain or embossed, for use as roofing or siding on general industrial buildings. It is available in prepainted colors.

Tapered Sheet and Plate. A rolled or machined product with the thickness tapered from one end to the other in the direction of rolling. Important uses include aircraft wing skin and large storage tanks.

Armor Plate. Wrought aluminum alloy plate for military vehicle armor.

Tread Plate. Sheet or plate with a raised, figured pattern on one surface to provide improved traction, or with abrasive granules imbedded in the surface.

Stainless-Clad Aluminum. Although it has other applications, this product was designed to provide a stainless steel inner liner for cooking utensils. It is produced in 3004 alloy with a 0.010-in. layer of 18-8 stainless steel roll bonded to one or both sides.

Boral Sheet and Plate. This product is a composite material with a core of boron carbide (B4C) dispersed in commercially pure aluminum and clad on both sides with aluminum, and it is employed as a neutron-shielding medium. It can replace large amounts of concrete or earth as a shielding medium and is therefore used where space and weight are factors.

Tooling Plate. A wrought or cast plate product for tool and jig applications.

Traffic and Street Sign Blanks. Standard sign blanks are precut from 6061-T6 alloy sheet in configurations and thickness established by the United States Bureau of Public Roads.

Tube-in-Sheet. By inserting long strips of resist (carbon-plastic-plaster "cores") in a sheet ingot, parallel passages are obtained in a sheet rolled from this ingot.

Roll-Bond Evaporator Sheet. Internal pressure is also applied to expand the maze of complicated passages in refrigerator evaporator sheet. This product is produced by bonding two sheets together under roll pressure after a stop-off has been printed on one of the sheets. This is done hot after both sheets have been wire brushed.

Foil

Commercial aluminum foil ranges in thickness from 0.00017 to 0.0059 in. and in width from 0.250 to 61 in. It is produced with two sides bright or one side bright and one satin finished. The latter, common for thickness less than 0.001 in., is produced by pack rolling: Two sheets of foil are passed through the rolling mill at the same time. The faces in contact with the rolls have a bright, specular finish, while the mating faces have a satin finish. Foil more than 0.001 in. thick is normally rolled in single sheets and is available with two sides bright.

Most foil applications are confined to 1145 alloy and to the 0 and H19 tempers. Household foil and other flexible packaging materials are almost always in the 0 temper, and various types of heat-and-serve rigid containers are in the H19 temper; 3003- H19 is also used in rigid containers. The ease with which foil can be coated, printed or combined by laminating with many flexible and rigid materials has greatly broadened the range of applications. It is available with heat-seal coatings, decorative lacquers, and a wide selection of protective coatings, films, and adhesives of varied compositions and thickness.


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