Copper planes of thicknesses between 0.006″ and 0.250″ with a width of 24″ or more are typically considered to be sheets, though regulations and categories may vary among manufacturers.
Though the copper sheets themselves are rarely finished products, they and products made from them are extremely versatile and widely employed across the industrial sector. Malleable and ductile copper sheets are easily formed into components such as flashing for roof tops, decorative paneling, plumbing fixtures, lighting, architectural features, heat exchanger parts, base plates and more. Many of these uses take advantage of the beneficial attributes of the base material, copper. Copper, and its alloys to varying degrees, is the best known economical conductor of electricity and heat.
It is also non-magnetic, durable and non-sparking making the use of copper sheeting within the petrochemical, chemical, automotive, architectural, building, construction, electronics, food processing, marine, aerospace, wiring, power generation, waste treatment, lighting and telecommunications industries very common. The particular range of thickness, or gauges, in which copper sheets are available make them a popular choice as they are easily formed to specific shapes, but sturdy enough to hold a solid form after processing.
The material choice of copper is economic both in terms of the material itself and in the cost of processing. Because the metal is soft and malleable, it is extremely energy efficient to process unlike some other sheet metals which require a great deal of pressure or heat to process. Several different processes such as extrusion, casting, cold rolling and drawing may be used, but roll forming is the most common method of sheet metal production. This involves heating copper billets, ingots or other raw forms to increase formability. The shapes are then fed through a pair of rollers that compress the metal into a thin sheet.
In some cases several rollers or several passes through the same rollers may be needed to reach the desired thickness which should be uniform throughout the sheet. In addition to thickness or gauge, length and width should also be taken into consideration. The purity of the copper used in sheet fabrication should also be considered as many popular alloys, such as bronze or brass, will have different mechanical properties. Hardness and surface properties of copper sheets can be altered during the rolling process as well as through intentional cross rolling. Regulatory bodies such as the American Society for Testing and Materials (ASTM) and the Copper Development Association (CDA) are good sources for information on copper sheets and most copper suppliers will also be able to help determine the proper specifications for a given application.