RPM Industries LLC

Overview of Aluminum Extrusions

The process of using a specific cross-sectional profile to transform aluminum alloy into objects is known as aluminum extrusions. The completed extrusions take full advantage of unique physical characteristics found in aluminum. As such, the metal becomes far more malleable, allowing it to be machined and cast more easily.

Because the aluminum extrusions have roughly 33 percent stiffness and density of steel, finished products are stable and strong, especially when other metals are alloyed. The outcome is aluminum extrusions that are used by many industries and for different applications.

The Making of Aluminum Extrusions

To create aluminum extrusions, certain steps are followed.

  • Die Shape and Design—Once the die shape and design are determined, aluminum alloy in the shape of a cylindrical billet is heated at anywhere between 800 and 925 degrees Fahrenheit.
  • Lubrication—From there, the billet is placed into a loader and a lubricant added. This prevents the aluminum from sticking to the machine, handle, or ram used to make extrusions.
  • Pressure—Next, a significant amount of pressure is applied using a ram to the dummy block. This ram pushes the billet into the container, followed by pushing it through the die.
  • Oxide Formation—To ensure that no oxides form, nitrogen in gaseous or liquid form is introduced. As this flows through the various parts of the die, an inert atmosphere is created. In addition, this lengthens the die’s life.
  • Extruded Part—The part then passes onto a runout table in an elongated piece that is the exact shape of the die opening. There it is pulled onto a cooling table and cooled by fans.
  • Cooled Extrusion—Once cooled, the extruded aluminum is straightened and work hardened on a stretcher.
  • Cutting—The aluminum extrusions are then cut by a table saw to the specified length.
  • Treatment—As the final step in creating aluminum extrusions, heat is used in special age ovens to speed up the aging process, thereby hardening the aluminum.

Depending on the customization required by the customer, other complexities may be added during the process of making aluminum extrusions. Because of the unique beneficial attributes, including ductility to conductivity, strength, recyclability, and non-magnetic properties, aluminum is considered a highly adaptable and viable solution for all types of manufacturing purposes.