Aluminum extrusion shapes profiles by forcing heated billets through a die, with material extending only in the cross-sectional direction to form constant-profile products. Its key advantages include high efficiency, excellent material utilization, and low tooling/unit costs—ideal for long lengths, large volumes, and fast turnaround.

A main limitation is that it only produces uniform cross-section parts (direct 3D geometry changes are difficult). However, combining it with secondary operations (CNC machining, drilling/tapping, cutting, welding) enables complex structures and high-precision assemblies while keeping extrusion’s cost benefits.

Extruded aluminum offers diverse cross-sections: solid, hollow, multi-cavity, and open structures (C-shaped, hat-shaped). It supports tailored stiffness-to-weight ratios and functional features (snap-fits, tracks, cable channels).

Optimizing wall thickness, corner radii, and rib placement helps balance strength, weight, and manufacturability—while ensuring stable extrusion flow.

Direct extrusion: Billet and ram move in the same direction relative to a fixed die.

Indirect extrusion: Die moves toward a stationary billet; metal flows opposite to ram travel.

Indirect extrusion reduces friction, enabling uniform flow, tighter tolerances, and better surface finish. It also produces seamless tubes—eliminating welded tube’s longitudinal weld lines for superior pressure integrity and fatigue performance.

Magnesium can also be extruded. Compared with aluminum extrusion, it has a weight advantage but requires stricter process control:

Narrower temperature range for processing

Higher sensitivity to oxidation and flow stability

More rigorous demands on equipment, tooling, and safety protocols

Aluminum extrusion dies are precision tools that shape heated aluminum billets into continuous profiles with fixed cross-sections. A standard die set includes the die (with profile orifice), backer, bolster, and support tooling.

Hollow profiles use porthole/bridge dies (with spider legs and mandrel) for internal voids.

Solid profiles rely on flat dies.

Die performance depends on steel grade/heat treatment, optimized flow channels, bearing lengths, and balanced ports—ensuring uniform metal flow, dimensional accuracy, surface finish, and long die life. Proper maintenance (nitriding, polishing, alignment, refurbishment) directly boosts productivity, cuts scrap rates, and maintains consistency.

Dies are built from customer-provided drawings or samples. For faster, more accurate engineering, supply native CAD or neutral 3D files (e.g., CAD, STEP/STP), plus key details: tolerances, alloy/temper, finish needs (e.g., anodizing), and expected press tonnage.

High-quality digital models enable quicker die design iterations, flow/bearing simulation, and smoother sample approval before mass production.

ensuring long-lasting performance in any environment.

On the extrusion press, preheated aluminum billets are pressed through a precision die under high pressure to form continuous profiles. Press capacity is measured in tons: larger or thicker profiles demand higher-tonnage presses to deliver enough extrusion force, ensuring stable material flow and consistent dimensions.

Preheat the die set, backer, bolster, and container to stabilize their dimensions and facilitate uniform metal flow. Heat billets to the target extrusion temperature—this achieves the required plasticity without causing incipient melting, reducing flow marks and initial production defects.

Load the heated billet into the container and conduct an upsetting process. This step ensures full contact between the billet and container, removes surface oxides, and prevents metal backflow. Proper upsetting minimizes defects like laps, pick-ups, and seams at the start of extrusion.

The ram pushes the billet through the die orifice: flat dies are used for solid profiles, while porthole/bridge dies with mandrels are applied for hollow ones. During this stage, control ram speed and metal exit temperature. Optimize flow via bearing lengths and port design to maintain dimensional accuracy, smooth surface finish, and strong weld lines.

Support the extruded profile on the runout table using pullers. This prevents the profile from sagging and vibrating (chatter) as it emerges.