T5 vs T6 Aluminum Temper for Extrusions
Specify material condition and evidence without treating temper as a universal performance rating.
Start with the purchase requirement
A quote for an aluminum profile should identify the alloy and temper together. T5 and T6 describe material treatment conditions; they are not coating names, product grades or automatic approvals for a load-bearing assembly. Keep the specified condition tied to the drawing and product standard, then request evidence for the delivered material. This guide focuses on understanding procurement labels rather than prescribing a furnace or quenching procedure.
Understand the material or process
AEC describes T5 as cooling from elevated temperature followed by artificial aging, and T6 as solution heat treatment followed by artificial aging. Its alloy-temper example joins the two labels, such as 6063-T5. A complete purchase requirement also needs the relevant product standard, geometry and acceptance evidence. The treatment label alone does not supply every property limit.
What to compare
| Field | T5 proposal | T6 proposal |
|---|---|---|
| Material identity | State the alloy as well as T5. | State the alloy as well as T6. |
| Treatment description | Cooling from elevated temperature followed by artificial aging. | Solution heat treatment followed by artificial aging. |
| Acceptance basis | Name the applicable product specification and required properties. | Use the applicable specification for this alloy and condition. |
| Fabrication state | Identify material condition before and after the quoted operations. | Identify material condition before and after the quoted operations. |
| Evidence | Link the required results and documents to the delivered lot. | Link the required results and documents to the delivered lot. |
| Alternative review | Record who accepts a change from the specified condition. | Record who accepts a change from the specified condition. |
Separate the label from the acceptance limits
Ask the requirement owner to identify the material condition and applicable product specification. A statement such as "T6 is stronger" is not enough to release an order: the alloy, product form, section and applicable limits must be known. When suppliers propose different conditions, put them in separate alternatives and ask which requirements change. Keep an unresolved value marked for clarification rather than filling it from an unrelated internet table.
Review operations after the extrusion
The quoted route may include bending, machining, joining, treatment and assembly. Ask the supplier to list these operations in order and explain whether they affect the specified material condition or the evidence required for the finished component. Do not assume a document for the starting extrusion establishes the state of every fabricated part. If joining is involved, have the responsible designer define the necessary review and acceptance requirements.
A practical quote clarification
A buyer requests a frame section with a drawing that specifies one alloy-temper combination. A supplier returns a price that names the alloy but omits the temper. Record this as missing information before comparing the offer. Ask the supplier to identify the proposed condition, controlling specification, supplied state and material document. If the supplier instead offers an alternative temper, keep its commercial and technical terms separate from the compliant quotation.
Plan sample and lot review
Define which trial pieces represent the proposed production route and which features are reviewed on them. Retain the sample identifier, drawing revision and any material or inspection reports. For the production order, agree how lot identification is maintained through cutting, finishing and packing. A sample review is useful only when the accepted scope and unresolved items are recorded; it should not erase missing production evidence.
Build your procurement checklist
- Alloy, required temper and designation system
- Record the controlled requirement, supplier proposal or unresolved question for this item.
- Product drawing revision and section reference
- Record the controlled requirement, supplier proposal or unresolved question for this item.
- Operations and material condition at delivery
- Record the controlled requirement, supplier proposal or unresolved question for this item.
- Product standard, property requirements and lot documents
- Record the controlled requirement, supplier proposal or unresolved question for this item.
- Supplier alternatives and responsible review decision
- Record the controlled requirement, supplier proposal or unresolved question for this item.
- Trial and production quantities
- Record the controlled requirement, supplier proposal or unresolved question for this item.
Continue from the requirement
Research supplier scope and source evidence, then confirm the exact material, operations and current commercial terms. The inquiry center prepares a draft addressed to Tony; it does not automatically send requests to directory companies. Add the downloaded checklist and drawings manually. Record a real acknowledgement separately from opening an email link.
Buyer questions
Does T6 mean a finished part is approved?
No. It identifies a treatment condition. The geometry, design, fabrication, inspection and applicable requirements still need review.
Can I order only by T5 or T6?
Include the alloy and relevant product specification. A temper label without material identity is incomplete.
Does the same temper guarantee the same properties in every alloy?
No. Determine the applicable limits for the alloy, product form and relevant section or thickness range.
Is a hardness result sufficient acceptance evidence?
Use the agreed inspection plan and product specification. Do not replace required documents or tests with an unrelated measurement.
Sources and review scope
AEC: alloy and temper descriptions · The Aluminum Association: designation systems and standards resources
Primary sources reviewed 3 October 2026. The comparison tables, examples and procurement checklists are AlumHome editorial guidance. Source organizations do not endorse these pages or linked suppliers. Use the applicable product documents and responsible design review for order acceptance.