What are the 5 steps of aluminum extrusion?

When buyers ask how aluminium profiles achieve tight tolerances and consistent finish, the answer is a repeatable five-step extrusion flow. Below is a plain-English breakdown you can share with engineers and procurement, plus exactly how Ghonor's China + Vietnam plants execute each stage for tile trims, hollow sections, L-/T-/square trims, frames, and other custom profiles.

 

 

Aluminium extrusion heats a solid billet and pushes it through a precision die to create a long profile with a constant cross-section. After it leaves the die, the profile is quenched (cooled), straightened and cut, then aged/finished to reach final properties and appearance. Extrusion is a solid-state forming process-the metal is hot and plastic, but not melted.

 

1) Design for extrusion + prepare the billet & die

What happens: You finalize the geometry; the die is manufactured and preheated. Billets are selected by alloy/temper and heated to the correct plastic-working range (commonly ~450–500 °C for 6xxx series). Die preheat and billet temperature control flow and surface quality.

Quality signal: Good suppliers confirm alloy, target tolerances (OD/width/height, wall), and critical radii before cutting metal.

How Ghonor does it: Our engineering team in China and Vietnam reviews drawings/targets and proposes DFM on wall, corner radii, bridge/tongue for hollows, and slot geometry (for trims). We maintain a 5,000+ mold library to shorten lead time when a near-match exists.

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2) Extrude (pressing through the die)

What happens: A hydraulic ram pushes the heated billet through the die; the profile emerges continuously with the die's shape-think "toothpaste from a tube," but with controlled metal flow and press speeds.

Quality signal: Stable press speed and bearing design help minimize die lines and dimensional drift.

How Ghonor does it: Our Vietnam base runs 12+ extrusion lines (600–2500 T) with a monthly 4,000–4,500 t capacity; China runs additional lines for regional programs. This spread lets us size the press to the section and maintain predictable queues for trials and mass production.

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3) Quench & cool (lock in properties)

What happens: The just-formed profile is sheared to the runout table and rapidly cooled-by air, water spray, bath, or mist-to "freeze" the alloying elements in solution and set up for the T5/T6 temper path. Proper quench is essential to final strength.

Quality signal: The supplier should be able to explain their quench method and why it fits your alloy/section thickness.

How Ghonor does it: We select air/mist/water quench modes by alloy and wall thickness, and we log quench parameters for the lot record used in your inspection pack.

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4) Stretch (straighten) & cut to length

What happens: After cooling, profiles go to a stretcher to relieve residual stress, correct bow/twist, and bring the section back into tight straightness; then they're saw-cut to exact lengths. This combination protects downstream machining and assembly fit.

Quality signal: Look for documented straightness/twist targets and evidence of calibrated stretch equipment.

How Ghonor does it: We specify straightness/twist per profile family (e.g., trims vs. structural tubes) and keep cut-length tolerances aligned to your install method (±0.5–1.0 mm typical for trims).

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5) Age, finish, inspect & pack

What happens: Heat-treat (natural or artificial aging) to reach the specified temper (e.g., T5/T6). Then apply the surface finish (anodize or powder coat), perform dimensional/coating/color inspections, and pack with damage control for long transit. Aging after quench is what delivers the final mechanical properties.

Quality signal: Coating thickness and ΔE color records, adhesion checks, and AQL cosmetics before pack-out.

How Ghonor does it:

Finishing in-house: automatic anodizing (including bright anodize), multiple powder-coating lines, and wood-grain thermal transfer.

Documentation: lot-linked material/heat data, coating thickness and color reports, photos.

Packaging: film wrap, separators, corner guards; cartons labeled with SKU/finish/length/lot/barcode.

 

 

It aligns drawings, tolerances, and inspection with how extrusions are actually made.

It clarifies where properties come from (quench + aging), not just alloy names.

It highlights the few checkpoints that most affect surface grade and assembly fit (die/bearing design, quench plan, stretch + length control). Industry primers from Hydro and technical notes on quench/aging echo the same sequence.

 

 

• Integrated Vietnam campus: one-stop flow from alloy verification → extrusion → anodizing/powder → punching/CNC → lab tests → kitting. The site covers ~140,000 m² and operates 12 extrusion lines (600–2500 T) with documented output and finishing cells designed for high cosmetic consistency.
• China factory for regional programs: established in 2007, 12,000 m² workshop with aluminium extrusion lines and independent stainless/PVC departments-ideal for Asia, Africa, and Middle East programs that need flexible MOQs and fast changes.
• R&D + mold library: 5,000+ molds, rapid DFM, and near-match proposals shorten sampling and reduce tooling risk for custom profiles.
• Quality system & certificates: ISO 9001/14001 and other audits; documented quality-inspection process from incoming to final AQL.
• Duty-smart origin: For U.S./EU/UK/AU/MX/CA buyers, our Vietnam origin can help legally avoid China-related anti-dumping exposure when the product and production path qualify; we provide origin documentation alongside your inspection pack.

 

 

 

• Profile + alloy/temper (e.g., 6063-T5/T6 or 6061-T6) and tolerance class (width/height/wall; straightness/twist).
• Surface: anodize (thickness, color/ΔE) or powder coat (film thickness, adhesion).
• Critical step controls you want reported: die preheat/billet temp range, quench method, stretch target, ageing schedule (T5/T6).
• Pack & labels for your channel: inner bundles, barcode, color chip, drop-test/ECT expectations.
• Origin & documents (Vietnam/CN) needed for your import program.

 

Send your CAD or target sizes. We'll return a step-linked control plan (die/billet settings → quench → stretch → age → finish), the inspection checklist we'll use on your lot, and a price/lead-time option from Vietnam (duty-optimized where applicable) and China (fast MOQs) so you can choose the best route for your market.