Aluminum extrusion dies are specialized, thick steel disks?typically made from H-13 tool steel?used to shape preheated aluminum billets into specific, continuous cross-sectional profiles. By utilizing hydraulic presses that apply up to 15,000 tons of pressure, softened aluminum is forced through the die's custom-machined openings to create everything from simple solid rods to complex hollow tubes.
How the Die Works in the Extrusion Process
The interaction between the die and the metal involves intense physical and thermal dynamics:
Heating: The die is preheated in a die oven to 750 degree - 900 degree F (400 degree - 500 degree C) to withstand the thermal shock and ensure even metal flow.
Pressing: A preheated aluminum billet (around 370 C degree - 500 degree C) is loaded into the press and forced through the stationary die by a hydraulic ram.
Shaping: The aluminum acts like a highly viscous fluid, flowing through the die apertures and taking the exact shape of the machined profile.
Cooling & Finishing: As the newly shaped aluminum emerges, it is quenched (cooled), straightened, and cut to desired lengths before secondary aging and surface treatments.
