Term and specification guide
What Is Aluminum Extrusion? A Buyer's Explanation
How aluminum extrusion works, what die, alloy, temper and tolerance labels mean, and what to verify when buying window profiles from Foshan.
Decision summary. Extrusion pushes aluminum through a die to create a fixed cross-section. For window profiles, the die, alloy, temper, wall thickness, tolerance and finish are separate things to specify and verify.
How the Component Works
A billet of aluminum is heated and pushed through a die whose opening has the shape of the desired cross-section. The resulting profile can be cut, machined, finished and assembled. Hollow sections, undercuts and thin walls require more complex dies and tighter process control than a simple solid shape.
For window profiles, extrusion produces the geometry, but it does not by itself deliver the window. Alloy, temper, wall thickness, straightness, surface finish and the fabricator's assembly all contribute to the final product.
Terms You May See in Supplier Listings
Extrusion listings mix process, material and commercial labels. Separate what the supplier can prove from what the page merely claims.
Alloy and Temper Labels
A label such as 6063-T5 combines an alloy family and a temper condition. 6063 is widely used for architectural extrusions, but the temper affects strength and cannot be inferred from the alloy name. A listing that says only "6063" leaves the temper, the actual wall thickness and the applicable tolerance open. Ask for the drawing, the temper and the lot certificate.
Die and Tolerance Claims
A die number identifies a specific cross-section. "Custom profile" does not. Ask whether the die already exists, who owns it, and which press will run it. Then define where wall thickness is measured, the allowed deviation, straightness and cut-length tolerance. A certificate that states the alloy but not the measured dimensions does not close the tolerance question.
What to Ask a Foshan Supplier
Ask for the die drawing, alloy and temper, wall thickness at named points, tolerance standard, finish specification, mill certificate and packing method. For a new die, ask for the tooling price, ownership, trial process and approval criteria. For an existing die, ask for the last production date and whether the die has been modified.
Common Misunderstandings
Extrusion is often described as if one number defines the whole profile. These corrections separate the variables.
- A thicker wall always means a better profile
- What is misleading: Alloy, temper, geometry, reinforcement and assembly also determine performance.
How to check: Specify all material and dimensional requirements and inspect them together. - "Custom profile" means a new die is included
- What is misleading: The seller may be using an existing die or a stock section.
How to check: Ask for the die number, its owner and the tooling line in the quotation. - An alloy certificate proves the dimensions
- What is misleading: A mill certificate may report composition and mechanical properties without the dimensional check the buyer needs.
How to check: Request a dimensional inspection record in addition to the material certificate.
Sources, Methodology and Research Limits
This page separates published source material from editorial recommendations. Supplier descriptions are treated as claims, not as verified capabilities. The research record below lists what was checked for Aluminum Extrusion.
Claims used on this page
public sourceverifiedExtrusion pushes material through a die to create a fixed cross-section; aluminum is the most commonly extruded metal and can form complex profiles.
Extrusion — Lead section and Materials section
Limits: General process description, not a supplier capability or tolerance statement; Die design, press size and alloy determine what a specific plant can produce.
analysisverifiedWindow and door frames are listed applications of 6063 aluminum extrusions; profile geometry, alloy, temper and wall thickness are separate variables.
6063 aluminium alloy — Uses section
Extrusion — Materials, aluminum
Limits: The sources establish general application, not the suitability of a particular profile for a particular window system; Wall thickness alone is not a quality verdict.
public sourceverified6063 is described as the most common alloy used for aluminium extrusion and is used for window and door frames; it is heat treatable and suitable for anodizing.
6063 aluminium alloy — Lead section and Uses section
Limits: Encyclopedia summary; alloy selection depends on the structural requirement and applicable standard; Other alloys such as 6061 or 6082 may be specified where higher strength is needed.
public sourceverifiedFor 6063 material up to 13 mm thick, published reference values give minimum ultimate tensile strength of 140 MPa for T5 and 190 MPa for T6, and minimum yield strength of 97 MPa for T5 and 160 MPa for T6.
6063 aluminium alloy — Mechanical properties, 6063-T5 and 6063-T6
Limits: Values are quoted from an encyclopedia summary of secondary sources, not from a mill certificate or the governing standard; Thickness, temper practice and the applicable product standard change the acceptance values; Do not use these figures as purchase acceptance limits without the cited standard.
Sources
- Extrusion. Wikipedia. Reference report. Accessed 10 November 2026.
What it supports: General explanation of extrusion, die cross-sections, hot extrusion and aluminum as a commonly extruded material.
Limits: Encyclopedia overview, not an extrusion tolerance or alloy standard; Process temperatures and equipment descriptions are general and not supplier-specific. - 6063 aluminium alloy. Wikipedia. Reference report. Accessed 10 November 2026.
What it supports: Overview of 6063 alloy composition, common extrusion use, window and door frame applications, and published T5 and T6 mechanical property values.
Limits: Encyclopedia summary of secondary sources, not the Aluminum Association standard itself; Property values depend on thickness, temper condition and product standard; they cannot be used as acceptance limits without the applicable specification.
Research limits
- Process description comes from a general encyclopedia article, not an extrusion standard.
- No die shop, press line or finishing line was visited.
- No supplier tooling quote or mill certificate was reviewed.
- No extrusion tolerance standard was reviewed.
- No tooling quote was collected.
Exclusions: Die cost quotes.; Plant audit.; Extrusion standard review..