Aluminum extrusion can be defined as the process or technique of transforming aluminum alloys into finished products with a cross-sectional profile for a wide variety of uses and applications. Die casting companies who perform the process of aluminum extrusion put in extra efforts to make the most of the unique physical characteristics of aluminum and its alloys. This in turn allows them to produce high-quality finished products with excellent physical properties.
The best thing about aluminum alloys is that they are easily malleable when compared to other metal alloys. The excellent malleability of these alloys enables die casters to easily machine and cast them without any difficulties. The stiffness and density of aluminum is almost one-third when compared to steel, which means that the products obtained through the aluminum extrusion process have greater stability and strength.
During the process of aluminum extrusion, die casters heat a cylindrical billet of aluminum alloy to 800 to 925°F after designing and deciding the shape of the die. The billet is moved to a loader, where die casters add a lubricant into it, which prevents the billet from sticking to the handle, ram, or the extrusion machine.
A ram is used to apply substantial amounts of pressure to a dummy, which in turn pushes the cylindrical aluminum billet to the container to form the die. Nitrogen is then introduced in gaseous or liquid form to avoid oxide formation during the process. Die casters allow nitrogen to flow through different sections of the die for the sole purpose of extending its life.
The extruded piece of aluminum alloy is passed through a run-out table and later transferred to a cooling table where fans are used to cool the final product. Once the cooling process is completed, a stretcher is used to straighten the extruded aluminum. In some cases, the extruded aluminum may also be cut to match the desired dimensions.
In the final step of the aluminum extrusion process, the newly extruded pieces of aluminum alloys are treated by subjecting them to high-temperature. This considerably speeds up the aging process of the extruded aluminum and hardens it. Die casters often incorporate additional techniques or processes to customize the extruded aluminum pieces in order to meet the requirements of their customers. Aluminum extrusions are used for a wide variety of applications such as in construction and transportation industries.