Aluminium 6061-T6
The default Indian structural aluminium — strength, machinability, weldability balance.
6061-T6 is a precipitation-hardened Al-Mg-Si alloy. UTS ~310 MPa, excellent corrosion resistance, anodisable, and the most widely-stocked aluminium across Hindalco, Balco, and Jindal in India. It's the default choice for general-purpose structural parts, mould bases, marine fixtures, and aerospace fittings up to 6 mm thickness.
Equivalent Designations
| Standard | Designation |
|---|---|
| UNS | A96061 |
| Werkstoff Nr. | 3.3211 |
| EN | EN AW-6061 |
| ISO | AlMg1SiCu |
| AA | AA6061 |
| BS (old) | HE20 |
Standards
ASTM B211 / ASME SB211 — rolled or cold-finished bar/rodASTM B221 / ASME SB221 — extruded bar/rodASTM B209 / ASME SB209 — sheet/plateAMS 4102, 4117, 4128, 4150, 4160 — aerospace temper-specificEN 2089 / 2395 (T6/T62/T4/T42 tempers)
Chemical Composition (% by mass)
| Si | 0.4–0.8 |
| Fe | 0.7 max |
| Cu | 0.15–0.40 |
| Mn | 0.15 |
| Mg | 0.8–1.2 |
| Cr | 0.15–0.35 |
| Zn | 0.25 |
| Ti | 0.15 |
| Al | Remainder |
| Other (each / total) | 0.005 / 0.15 |
Mechanical Properties
| Ultimate Tensile Strength | 310 MPa (45 000 psi) |
| Yield Strength (0.2%) | 276 MPa (40 000 psi) |
| Shear Strength | 214 MPa (31 000 psi) |
| Elongation in 2″ | 12 % |
| Brinell Hardness | 95 HB |
Physical Properties
| Density | 2.82 g/cm³ |
| Melting Point | 535 °C |
| Modulus of Elasticity | 71 GPa |
| Thermal Conductivity | 138 W/m·K |
| Thermal Expansion | 23×10⁻⁶ /K |
| Electrical Resistivity | 0.045×10⁻⁶ Ω·m |
Available Forms & Sizes
| Form | Size Range | Notes |
|---|---|---|
| Round Bar | Ø6 mm to Ø200 mm | Tempers T3, T4, T5, T6, T651, T6511 |
| Square Bar | 16 mm to 100 mm side | — |
| Flat Bar | 5 mm to 500 mm width | — |
| Plate/Sheet | 0.2 mm to 300 mm thick × 500–2500 mm width × 500–10000 mm length | — |
| Hex Bar | On request | — |
Tempers Available
Finishes Available
Use Cases
Mould bases (low-volume tooling)
Default for cavity/core blocks where pre-hardened steel is overkill. Machinability and dimensional stability post-anneal.
Aerospace structural fittings
Brackets, stringer fittings, fairing supports. Specify T651 plate (stress-relieved by stretching) for thicknesses > 6 mm to control machining-induced warpage.
Marine fixtures, hulls, sailboat masts
Corrosion-resistant in salt-water exposure when properly anodised. Compatible with epoxy primer for added protection.
Drone airframes, gimbal housings, rover chassis
Strength-to-weight balance and easy anodising for cosmetic finish.
Optical / scientific bench plates
Flatness can be machined to ±0.05 mm/m on T651 with proper fixturing.
Heat exchangers, EV battery cooling plates
Good thermal conductivity (138 W/m·K) and weldability (TIG with 4043 or 5356 filler).
Design Notes
- Welded HAZ loses ~50% strength — design joints to put welds in low-stress zones, or specify post-weld heat treatment.
- Anodises consistently to silver/gold — preferred over 2024 (which yellows due to copper) for cosmetic anodised parts.
- T651 vs T6: T651 plate has been stress-relieved by stretching after solution treatment. Always specify T651 for machined plate >6 mm to avoid warp.
Indian Sourcing
Hindalco and Balco often supply 6061 and 6082 interchangeably. If your application is genuinely sensitive to alloy composition (welded structure or stress-bearing aerospace), specify the heat-number lot and demand a chemical-analysis MTC. Otherwise 6082 is a perfectly acceptable substitute for 6061 in ~95% of Indian use cases.