Aluminum suppliers make many aluminum shapes available to their clients. Patrons of aluminum suppliers make use of aluminum shapes for many purposes. Because of this diversity of products and applications, it is impossible to arrest an all-encompassing definition of an aluminum bar and its applications. Generally speaking, an aluminum bar is any simple aluminum shape that is characterized by a longer length than width.
Such a shape can be round or polygonal; an aluminum bar’s shape depends on its intended application. For example, an aluminum bar that has just emerged from a primary supplier is not likely to be ready for use. Instead, it is likely to be shipped to a metalworking or forging operation where it will be shaped into something usable. On the other hand, aluminum bars that have emerged from metal shaping processes can be useful; such products are often used to make railings, stakes and tines. Such bars are often referred to as rods.
The word “billet” is more commonly used to refer to raw industrial ingredients. Billets made from aluminum, which are semi-finished bar stock, go through extrusion to become bar-shaped. They are heated to 900°F, placed in an extrusion press and drawn. Drawing refers to pushing the billet through a steel die by a large, hard metal ram under pressure. They are often pushed through consecutively smaller dies multiple times in order to reduce their cross section a little at a time.
Larger bars may only be extruded once, while small bars are often put through the process more than twice. Liquid nitrogen is often poured after the bar is extruded to cool the material. Once the material has cooled, it can be shipped to customers or sent for further processing. Although many bars require no sort of cold working, those that are often exhibit an improved surface finish and dimensional tolerances.