6061 aluminum alloy is one of the most widely used aluminum alloys in the world. It offers an excellent combination of strength, corrosion resistance, and machinability. Whether you are sourcing 6061 aluminum alloy for structural parts, marine applications, or precision machining, this guide covers everything you need to know — from chemical composition and mechanical properties to pricing and supplier advantages.
What Is 6061 Aluminum Alloy?
6061 aluminum alloy belongs to the 6xxx series, which uses magnesium and silicon as primary alloying elements. It is a heat-treatable alloy that can be significantly strengthened through artificial aging. The most common temper is T6, producing a high-strength product known as 6061-T6 aluminum alloy. The T651 variant (stress-relieved plate) is also widely specified for precision machining applications.
This alloy is sometimes called 6061 grade aluminum alloy in procurement documents. It meets ASTM B209, AMS 2770, and ISO 6361 standards.
Chemical Composition of 6061 Aluminum Alloy
The chemical composition of 6061 aluminum alloy is tightly controlled to ensure consistent mechanical performance. The alloy is 97.9% aluminum by weight, which answers the common question: What percent of 6061 aluminum alloy is actually aluminum?
| Element | Min (%) | Max (%) | Typical (%) |
|---|---|---|---|
| Aluminum (Al) | Balance | Balance | ~97.9 |
| Silicon (Si) | 0.40 | 0.80 | 0.60 |
| Magnesium (Mg) | 0.80 | 1.20 | 1.00 |
| Copper (Cu) | 0.15 | 0.40 | 0.28 |
| Iron (Fe) | — | 0.70 | 0.50 |
| Chromium (Cr) | 0.04 | 0.35 | 0.20 |
| Zinc (Zn) | — | 0.25 | 0.10 |
| Manganese (Mn) | — | 0.15 | 0.05 |
| Titanium (Ti) | — | 0.15 | 0.05 |
| Other (each) | — | 0.05 | — |
| Other (total) | — | 0.15 | — |
What does silicon add to 6061 aluminum alloy? Silicon improves fluidity during casting and combines with magnesium to form Mg₂Si precipitates during heat treatment. These precipitates are the primary source of strength in the T6 temper. The 6061 aluminum silicon content (0.40–0.80%) is carefully balanced to maximize age-hardening response.
The aluminium alloy 6061 composition also includes chromium, which refines grain structure and improves resistance to stress corrosion cracking.
6061 Aluminum Alloy Properties
Mechanical Properties of 6061 Aluminum Alloy
The mechanical properties of 6061 aluminum alloy vary by temper. The T6 and T651 tempers are the most commonly specified.
| Property | 6061-O (Annealed) | 6061-T6 / T651 | Unit |
|---|---|---|---|
| Tensile Strength | 124 | 310 | MPa |
| Yield Strength (0.2% offset) | 55 | 276 | MPa |
| Elongation (2 in gauge) | 25 | 12 | % |
| Hardness (Brinell) | 30 | 95 | HB |
| Shear Strength | 83 | 207 | MPa |
| Fatigue Strength | 62 | 97 | MPa |
The 6061 aluminum alloy yield strength in the T6 temper is 276 MPa — high enough for structural applications. The tensile strength of 6061 aluminum alloy reaches 310 MPa in T6 condition, which provides significant safety margins in engineering design.
Is 6061 aluminum alloy strong? Yes. Compared to other aluminum alloys, 6061-T6 is considered strong. Its yield strength of 276 MPa outperforms 1100, 3003, and 5052 alloys by a wide margin. While it is not as strong as 7075-T6, it offers a far better balance of strength, weldability, and corrosion resistance for most applications.
6061 Aluminium Alloy Properties — Physical Data
| Property | Value | Unit |
|---|---|---|
| Density | 2.70 | g/cm³ |
| Melting Range | 582 – 652 | °C |
| Thermal Conductivity | 167 | W/m·K |
| Electrical Conductivity | 43 | % IACS |
| Coefficient of Thermal Expansion | 23.6 | µm/m·°C |
| Specific Heat Capacity | 896 | J/kg·K |
6061 Aluminum Alloy Density
The 6061 aluminum alloy density is 2.70 g/cm³ (0.0975 lb/in³). This is the same density value for both O and T6 tempers — heat treatment changes strength but not density. This lightweight characteristic makes 6061 aluminum alloy approximately one-third the weight of steel, which is a major reason it is chosen over steel in weight-sensitive designs.
6061 Aluminum Alloy Young’s Modulus
The 6061 aluminum alloy Young’s modulus is 68.9 GPa (10,000 ksi). This elastic modulus value is consistent across all tempers. Engineers rely on this value for deflection and stiffness calculations in structural and mechanical components.
| Elastic Property | Value | Unit |
|---|---|---|
| Young’s Modulus (Modulus of Elasticity) | 68.9 | GPa |
| Shear Modulus | 26 | GPa |
| Poisson’s Ratio | 0.33 | — |
| Bulk Modulus | 67.6 | GPa |
The 6061 T6 aluminum alloy modulus of elasticity is the same as other tempers: 68.9 GPa. Temper designation does not affect elastic modulus.
Difference Between 6061-T6 and 6061 Alloy (Other Tempers)
A common question: What is the difference between 6061-T6 and 6061 alloy?
6061 refers to the base alloy composition. The temper designation (O, T4, T6, T651, etc.) describes the thermal and mechanical treatment applied after casting or extrusion.
| Temper | Process | Yield Strength | Tensile Strength | Key Use |
|---|---|---|---|---|
| 6061-O | Annealed (fully soft) | 55 MPa | 124 MPa | Forming, deep drawing |
| 6061-T4 | Solution heat treated + naturally aged | 145 MPa | 241 MPa | Moderate strength, formable |
| 6061-T6 | Solution heat treated + artificially aged | 276 MPa | 310 MPa | Structural, machined parts |
| 6061-T651 | T6 + stress relieved by stretching | 276 MPa | 310 MPa | Precision plate, tight tolerances |
The 6061 T651 aluminum alloy is preferred for plate applications where residual stress must be minimized — such as mold tooling, aerospace ribs, and precision fixtures.
Does 6061 Aluminum Alloy Rust?
Does 6061 aluminum alloy rust? No — aluminum does not rust. Rust is iron oxide, and 6061 contains no iron as a primary alloying element. Instead, aluminum forms a thin, stable aluminum oxide (Al₂O₃) layer on its surface that protects against further oxidation.
However, 6061 aluminum alloy can suffer from other forms of corrosion in aggressive environments:
- Pitting corrosion — in chloride-rich environments (seawater)
- Galvanic corrosion — when in electrical contact with dissimilar metals
- Crevice corrosion — in tight joints with moisture
The chromium content in 6061 (0.04–0.35%) specifically helps resist stress corrosion cracking. For marine or outdoor applications, anodizing or coating provides additional protection.
6061 Alloy vs Steel: Key Comparison
| Property | 6061-T6 Aluminum | Mild Steel (A36) | Stainless Steel 304 |
|---|---|---|---|
| Density | 2.70 g/cm³ | 7.85 g/cm³ | 8.00 g/cm³ |
| Tensile Strength | 310 MPa | 400 MPa | 515 MPa |
| Yield Strength | 276 MPa | 250 MPa | 207 MPa |
| Young’s Modulus | 68.9 GPa | 200 GPa | 193 GPa |
| Corrosion Resistance | Excellent | Poor (rusts) | Good |
| Weight (relative) | 1× | ~2.9× heavier | ~3× heavier |
| Machinability | Excellent | Good | Fair |
| Weldability | Good | Excellent | Good |
| Specific Strength | High | Moderate | Moderate |
6061 alloy vs steel: While steel has higher absolute strength, 6061-T6 aluminum offers a better strength-to-weight ratio and far superior corrosion resistance. Its yield strength of 276 MPa actually exceeds mild steel (250 MPa), while weighing only one-third as much. This makes 6061 aluminum the preferred choice for aerospace frames, automotive components, and marine structures.
What Is 6061 Aluminum Alloy Used For?
What is 6061 aluminum alloy used for? The applications are extremely broad due to its excellent all-around properties.
Structural & Engineering Applications
- Structural frames and trusses
- Bridges and walkways
- Machine parts and fixtures
- Hydraulic manifolds and fittings
Aerospace & Defense
- Aircraft fuselage skins and ribs
- Helicopter components
- Military vehicle armor panels
- Missile fin assemblies
Marine Applications
- Boat hulls and deck fittings
- Docks and marine hardware
- Submarine pressure housings
Automotive & Transportation
- Truck chassis components
- Suspension arms
- Rail car structures
- EV battery enclosures
Consumer & Industrial
- Electronic chassis and heat sinks
- Sporting goods (skis, climbing gear)
- Architectural extrusions
- Piping and pipeline fittings
6061 Aluminum Alloy Product Forms
We supply 6061 aluminum alloy in the following product forms:
| Product Form | Available Tempers | Thickness / Size Range |
|---|---|---|
| Sheet & Plate | O, T4, T6, T651 | 0.3 mm – 200 mm thick |
| Coil | O, T4, H tempers | 0.2 mm – 6.0 mm |
| Extrusion (Bar, Rod, Profile) | T5, T6 | Custom cross-sections |
| Tube & Pipe | T6 | OD 6 mm – 600 mm |
| Forging | T6, T652 | Custom dies available |
6061 Aluminum Alloy Price
The 6061 aluminum alloy price depends on several factors: LME aluminum spot price, alloy premium, temper processing cost, product form (sheet vs. plate vs. extrusion), and order quantity.
| Factor | Typical Impact on Price |
|---|---|
| Base metal (LME Al) | ~60–70% of total cost |
| Alloy premium (Mg, Si, Cu) | +3–5% |
| T6 heat treatment | +8–15% vs. O temper |
| Precision plate (T651) | +15–25% vs. T6 sheet |
| Minimum order quantity | Discounts from 2MT+ |
| Certification (aerospace) | +10–20% |
For current 6061 aluminum alloy price quotations — including aluminum 6061 T6 prices per kg for different thicknesses and quantities — please contact our sales team directly. We offer competitive ex-works pricing with LME-linked transparency.
Note: Prices fluctuate with LME aluminum. We provide firm quotations valid for 7–14 business days.
Our Advantages as a 6061 Aluminum Alloy Manufacturer
As a direct manufacturer of 6061 aluminum alloy products, we offer:
Production Capabilities
- In-house casting, rolling, and heat treatment lines
- ISO 9001:2015 quality management system
- Full traceability from melt to finished product
- Mill test certificates (MTC) with every order
Technical Support
- Material selection assistance (alloy and temper)
- Custom thickness and width tolerancing
- Third-party testing coordination (SGS, Intertek, BV)
- Full PDF data sheets: aluminium 6061 T6 properties PDF available on request
Competitive Pricing
- Direct factory pricing — no middlemen
- Volume discounts starting at 2 metric tons
- LME-linked pricing with full cost transparency
Quality Assurance
- Tensile testing per ASTM E8
- Hardness testing (Brinell and Rockwell)
- Chemical analysis by OES spectrometer
- Dimensional inspection with CMM
Export Markets & Delivery
We regularly export 6061 aluminum alloy to:
North America: USA, Canada, Mexico
Europe: Germany, Netherlands, Italy, Spain, Poland
Middle East: UAE, Saudi Arabia, Turkey, Israel
Asia-Pacific: Australia, South Korea, Japan, Vietnam, Thailand
South America: Brazil, Chile, Colombia
Standard lead time: 15–25 days for stock items; 30–45 days for custom specifications. We work with major freight forwarders for sea, air, and rail shipments. Export documentation including CO, fumigation certificate, and SGS inspection reports are available.
Frequently Asked Questions
Q: What percent of 6061 aluminum alloy is actually aluminum?
A: Approximately 97.9% by weight. The remaining ~2.1% consists of alloying elements: primarily magnesium (1.0%), silicon (0.6%), copper (0.28%), iron (0.5%), and chromium (0.20%).
Q: Is 6061 alloy good?
A: Yes — 6061 aluminum alloy is widely regarded as one of the best general-purpose aluminum alloys. It combines high strength (especially in T6 temper), excellent corrosion resistance, good weldability, and outstanding machinability. It is cost-effective and available in many product forms globally.
Q: What is the difference between 6061-T6 and 6061 alloy?
A: “6061” refers to the alloy composition. “T6” is a temper designation meaning the alloy was solution heat treated and then artificially aged to peak strength. T6 has significantly higher strength (310/276 MPa tensile/yield) compared to the annealed O temper (124/55 MPa).
Q: Does 6061 aluminum alloy rust?
A: No. Aluminum does not rust. It forms a protective aluminum oxide layer. However, it can corrode under certain conditions (chloride exposure, galvanic coupling). Anodizing or coating extends service life in harsh environments.
Q: What is 6061 aluminum silicon content?
A: Silicon content in 6061 is 0.40–0.80%, with a typical value of ~0.60%. Silicon combines with magnesium during T6 heat treatment to form Mg₂Si strengthening precipitates.
Request a Quote for 6061 Aluminum Alloy
Ready to source 6061 aluminum alloy for your project? We supply sheet, plate, coil, extrusion, and custom-cut parts in all standard and non-standard tempers. Our team responds within 24 hours.
Contact us with your requirements:
- Alloy & temper (e.g., 6061-T6, 6061-T651)
- Product form (sheet / plate / bar / tube)
- Dimensions (thickness × width × length)
- Quantity (kg or metric tons)
- Destination port
We look forward to being your trusted 6061 aluminum alloy supplier.