6061 Aluminum Sheet and Plate

What Is 6061 Aluminum?

6061 is a heat-treatable Al-Mg-Si wrought alloy — the most widely used aluminum alloy in the world. With magnesium (0.8–1.2%) and silicon (0.4–0.8%) forming the strengthening phase Mg₂Si, plus a small copper addition (0.15–0.4%) for enhanced age-hardening, 6061 delivers a rare combination of:

Often called the "all-purpose aluminum alloy", 6061 is the default choice for structural parts, CNC-machined components, jigs/fixtures, and general engineering where a good balance of strength, corrosion resistance, machinability, and cost is needed.

Equivalent Designations

Product Specifications

Temper Selection Guide

Quick Comparison

Quick rule: O for maximum forming → T4 for form-then-age → T6 for general-purpose strength → T651 for thick plate and precision machining stability.

Temper Details

6061-O — Maximum Formability

• Fully annealed: lowest strength but highest ductility (≥25% elongation).
• Ideal for deep drawing, spinning, and complex cold forming.
• Can be subsequently solution-treated and aged to T6 strength.

6061-T4 — Form Then Age

• Solution treated at ~530°C (water quenched) + naturally aged at room temperature.
• Retains high ductility (≥22% elongation) for complex forming, then can be artificially aged to T6.
• Use when: Parts require severe forming that T6 cannot tolerate.

6061-T6 — The Standard

• Solution treated + artificially aged (160–175°C for 8–18 hr).
• UTS ≥290 MPa, Yield ≥241 MPa — the benchmark for structural aluminum.
• Excellent machinability, good anodizing response.
• Best for sheet-gauge parts (≤6 mm) and general CNC machining.

6061-T651 — Precision Plate

• T6 aging + 1–3% controlled stretching to relieve residual stress.
• Near-identical strength to T6 but with superior dimensional stability during machining.
• Mandatory for: Thick plate (≥6 mm), precision molds, jig plates, optical benches, aerospace tooling.

Heat Treatment Parameters

Chemical Composition (per ASTM B209)

Physical Properties

Mechanical Properties

Notes:

• Values per ASTM B209 for standard thicknesses. Very thick plate (>100 mm) may have slightly lower yield.
• Fatigue strength: ~97 MPa at 5 × 10⁸cycles (T6, R =−1).
• T651 has identical strength to T6 but superior dimensional stability for precision machining.

Processing & Fabrication

Machining

6061-T6/T651 is one of the most machinable aluminum alloys — a primary reason for its popularity.

Tip: Always machine in T6 or T651 temper. O temper produces long, stringy chips and poor surface finish.

Forming

Welding

Critical: Unlike 5xxx alloys, 6061 loses significant strength in the HAZ when welded in T6 condition. Design weld joints for O-temper strength unless PWHT is planned.

Surface Treatment

6061 vs. Other Alloys

When to Choose 6061

Applications

Aerospace & Defense

• Tooling & jigs: T651 plate for molds, fixtures, optical benches (superior dimensional stability)
• Structural parts: Wing ribs, fuselage frames, landing gear brackets (AMS 4027 / 4117 certified)
• UAV frames: Lightweight + machinable

Marine & Offshore

• Structural fittings: Masts, deck hardware, porthole frames (anodized T6)
• Desalination equipment: Housings and frames with Type III hard anodizing

Note: For structural marine hull plate in seawater, 5083-H116 is the classification-required alloy. 6061 is used for fittings and above-waterline structures.

Transportation

• Automotive: Bumper beams, battery trays, structural reinforcements (T6)
• Bicycle & motorcycle: Frames, swingarms, handlebar stems
• Rail: Interior structural members, equipment racks

Electronics & Electrical

• Heat sinks: Thermal conductivity 167 W/m·K (T6); CNC-machined fin arrays
• Enclosures: 5G base station housings, instrument cases, laptop chassis
• Battery trays: EV battery pack structural frames

Precision Machining & Industrial

• Mold bases: T651 with flatness ≤0.1 mm/m
• Hydraulic manifolds: CNC-machined from T651 plate
• Robotic components: Arm links, end-effector plates
• Pressure vessels: ASME-coded (moderate pressure/temperature)

Stock Inventory (Excerpt)

We stock 6061 in T6 (sheet) and T651 (plate) across a comprehensive thickness range. Contact us for full availability and custom cutting.

6061-T6 Sheet

6061-T651 Plate

All material supplied with mill test reports. O and T4 tempers available on request.

Packaging & Shipping

Pricing

FOB Price = SMM A00 Ingot Price + Processing Fee

Transparent formula; quoted in USD / EUR / CNY. 72-hour rush delivery available.

Why Choose Us for 6061?

When precision matters, the quality of your raw material dictates the success of your final product.

• State-of-the-Art German Mills: Rolled on an SMS Group 4500mm hot rolling line and a 2800mm CVC cold rolling mill. This guarantees ultra-low thermal deformation and surface roughness (Ra ≤ 0.8μm).
• Certified for the Skies: We operate under strict ISO 9001, AS9100 (Aerospace), Nadcap, and TS16949 (Automotive) quality management systems.
• Flawless Delivery: All T6/T651 plates are laminated with protective PVC film in dust-free workshops and shipped on IPPC fumigated wooden pallets to ensure zero transit damage.

Ready to start your next machining or structural project?
Contact our engineering sales team today for rapid quoting, custom cutting requirements, and full material test reports (MTRs).

FAQ

What is the tensile strength of 6061-T6?

Per ASTM B209, the minimum tensile strength of 6061-T6 is 290 MPa (42 ksi), with a typical value of ~310 MPa. Minimum yield strength is 241 MPa (35 ksi). These values apply to standard sheet and plate thicknesses; very thick plate (>100 mm) may have marginally lower minimums.

What is the difference between 6061-T6 and T651?

Mechanical properties are essentially identical (UTS ≥290 MPa, Yield ≥241 MPa). The difference is stress relief: T651 is stretched 1–3% after quenching to eliminate residual internal stresses. This makes T651 the correct choice for thick plate (≥6 mm) and any part requiring precision machining — it resists warping and distortion during material removal.

Can 6061 be welded?

Yes — 6061 is weldable with TIG or MIG using ER4043 (general purpose) or ER5356 (higher weld strength, better corrosion resistance) filler. However, the heat-affected zone (HAZ) reverts to near-O temper strength (~124 MPa) — a ~57% loss from T6. Post-weld re-aging at ~175°C can recover HAZ strength to approximately T4 level (~205 MPa). Full T6 recovery requires complete re-solution treatment + aging.

6061 vs 7075 — which should I choose?

6061-T6 is the all-purpose choice: good strength (290 MPa), excellent machinability, weldable, anodizable, moderate cost. 7075-T6 offers ~75% more strength (510+ MPa) but is harder to machine, essentially unweldable, less corrosion-resistant, and significantly more expensive. Choose 7075 only when maximum strength is the overriding requirement (aerospace primary structure, high-load military components).

Is 6061 suitable for marine use?

Yes — for above-waterline fittings, masts, deck hardware, and structural brackets, 6061-T6 with anodizing performs well. For submerged or splash-zone hull plating on classified vessels, 5083-H116 is required by class societies (DNV, ABS). 6061 contains Cu (0.15–0.4%), which makes bare 6061 more susceptible to pitting in seawater than Cu-free 5xxx alloys.

What is the minimum bend radius for 6061-T6?

Approximately 3× material thickness (bend ⊥ to rolling direction). For tighter bends, use O or T4 temper (min. radius ~1.5t), then age to T6 after forming.

Can 6061 be anodized?

Yes — 6061 is one of the best aluminum alloys for anodizing. Type II (5–25 μm) provides corrosion protection and accepts decorative dyes. Type III hard anodize (25–75 μm) delivers high wear resistance (HV 350–500) for aerospace and industrial applications.