6063 Aluminum Round Tube

6063 alloy round tube is a magnesium-silicon forged aluminum alloy optimized for extrusion, offering a balanced combination of medium strength, excellent surface finish, and superior corrosion resistance, making it a preferred choice for architectural and structural applications.

6063 aluminum alloy round tube is an aluminum alloy tube with excellent extrudability, good surface treatment performance, and outstanding corrosion resistance. It is commonly used in architecture, decoration, and public infrastructure, especially suitable for structural elements such as balcony railings, window frames, and curtain walls. Due to its high surface finish, 6063 aluminum alloy is also well-suited for anodizing, thereby enhancing its weather resistance and aesthetics.

6063 alloy round tube is typically in T6 temper, and also performs well in thermal dissipation applications such as radiators and bus conductors. Its fine-grained microstructure allows for excellent anodizing quality—even hard coating—while maintaining good weldability and machinability for complex assemblies. Standard tolerances under AMS-QQ-A-200/9 ensure high precision in outer diameter and wall thickness, meeting the demanding requirements of applications in construction, transportation, and industrial systems.

6063 alloy belongs to the 6000 series aluminum-magnesium-silicon alloys and is standardized by the Aluminum Association of America as AA 6063. Due to its extensive use in exposed extrusions such as doors and windows, it is commonly referred to as the "architectural alloy."

6063 Aluminum Round Tube Characteristics

• Excellent extrudability: 6063 aluminum alloy has very good extrudability, making it suitable for the production of high-precision, complex-shaped aluminum profiles. After extrusion, the finished product has a high surface finish, which is ideal for further surface treatments such as anodizing, coating, etc.
• Corrosion resistance: 6063 aluminum alloy has excellent corrosion resistance, especially when exposed to humid environments, offering better resistance to corrosion. It is suitable for outdoor and marine applications and is particularly ideal for use in construction and decorative structures in damp climates and marine environments.
• Surface treatment performance: 6063 aluminum alloy tubes have excellent surface finish and can undergo various surface treatments such as anodizing, electroplating, and coating. These surface treatments not only enhance its corrosion resistance but also improve its appearance, making it widely used in high-end decoration and construction fields.
• Mechanical properties: Although 6063 aluminum alloy has relatively low strength, it possesses good formability and weldability, meeting the needs of various light structural and decorative applications. Its tensile strength is moderate, making it suitable for the manufacture of structural parts, but not ideal for high-load applications.
• Welding performance: 6063 aluminum alloy has excellent weldability, and can be subjected to common welding processes such as TIG welding (tungsten inert gas welding).
• Machining/grinding performance: 6063 aluminum alloy has good machinability, allowing for operations like cutting, drilling, and grinding. During processing, the material remains stable, ensuring dimensional accuracy and surface quality.
• Bending/formability: This alloy also has good bending and forming capabilities, making it suitable for producing tubes and frame structures that require bending.
• Abrasion resistance: 6063 aluminum alloy has poor abrasion resistance, meaning it performs poorly in high-wear applications. For applications requiring high abrasion resistance, other aluminum alloys are typically chosen.
• Strength and applications: 6063 aluminum alloy has lower strength compared to other high-strength aluminum alloys, but its unique advantages lie in its surface finish and corrosion resistance, making it suitable for lightweight structural applications and decorative uses. Common applications include balcony railings, window frames, stair handrails, curtain walls, marine and ship decorative structures, external piping, and power equipment enclosures.

6063 Aluminum Round Tube Chemical Composition

• Aluminum (Al): 97.5%–99.35% (by weight)
• Magnesium (Mg): 0.45%–0.90%
• Silicon (Si): 0.20%–0.60%
• Iron (Fe): ≤ 0.35%
• Trace elements (Copper, Manganese, Chromium, Titanium, Zinc): each ≤ 0.10% (Total ≤ 0.15%)

6063 Aluminum Round Tube Physical and Mechanical Properties

6063 Aluminum Round Tube Physical Properties

• Density: 2.69 g/cm³
• Thermal Conductivity: 201–218 W/m·K
• Coefficient of Thermal Expansion: 2.34 × 10⁻⁵ K⁻¹
• Melting Range: 616–654 °C

6063 Aluminum Round Tube Mechanical Properties in Different Tempers

• T6 (solution heat-treated and artificially aged): Ultimate Tensile Strength (UTS) ≥ 28, 000 psi (193 MPa), Yield Strength (Y) ≥ 23, 000 psi (158 MPa), Elongation (Y) ≥ 8% (≤ 0.124 inch) or ≥ 10% (> 0.124 inch).
• T5 (cooled and artificially aged): Ultimate Tensile Strength (UTS) ≥ 20, 000 psi (138 MPa), Yield Strength (Y) ≥ 13, 000 psi (90 MPa), Elongation (Y) ~ 8%.
• O (annealed): Ultimate Tensile Strength (UTS) ≤ 19, 000 psi (131 MPa), Elongation (Y) ~ 18%.

6063 Aluminum Round Tube Specifications

• Outer Diameter (OD): Ranges from 1/4 inch (6.35 mm) to 3.5 inches, with common industrial sizes including 1.625-inch OD and 0.125-inch wall thickness.
• Wall Thickness: Extruded tubes typically range from 0.04 inch to 0.125 inch, with custom options available.
• Length: Standard lengths include 36 inches (for DIY) and 4 inches (industrial use) to 24 feet (industrial use).
• Surface Treatment: Suitable for uniform polishing, anodizing, chemical polishing, and dyeing.

Tolerances and Dimensions

According to AMS-QQ-A-200/9 standards, standard production tolerances for 6063-T6 round tubes are as follows:

• Outer Diameter Tolerance: Standard size ± 0.010 inch
• Wall Thickness Tolerance: ±10% of specified thickness
• Ovality: Typically ≤ 0.020 inch.

Special precision grades (e.g., drawn tubes) can achieve tighter controls, such as 1¾ inch OD, 0.058 inch wall thickness, and minimal ovality, suitable for pneumatic applications.

6063 Aluminum Round Tube Applications

• Construction industry: 6063 aluminum round tube is used in window frames, door frames, balcony railings, stair handrails, skylights, and other building decorative structures.
• Marine applications: Due to its corrosion resistance, 6063 aluminum alloy is also commonly used in shipbuilding, marine platforms, and other decorative structures.
• Public facilities: Used in power equipment enclosures, lamp posts, public facility frames, etc.
• Decoration industry: 6063 aluminum round tube is suitable for fine decorative strips, metal ornaments, display racks, and other applications.

Corrosion Resistance and Durability of 6063 Aluminum Round Tube

6063 aluminum tubes exhibit excellent corrosion resistance under most atmospheric conditions and perform well in many marine environments. Unlike alloys with higher magnesium content (such as 5083), the low magnesium content of 6063 aluminum tubes effectively mitigates stress corrosion cracking. Anodized coatings further extend their service life in corrosive environments.

Manufacturing and Processing of 6063 Aluminum Round Tube

Extrusion: Most 6063 tubes are formed through extrusion, which enables cost-effective production of uniformly shaped tubes.

Seamless and Structural Use:

• Seamless: Offers higher precision and better corrosion resistance, suitable for hydraulic or pneumatic systems.
• Structural: More cost-effective, used for framing and protective structures.
• Surface treatment: Options include mill finish, anodizing (to enhance corrosion resistance), and powder coating.

Extrusion and Tempering

The formulation of 6063 provides excellent extrudability, allowing for the production of smooth-surfaced, thin-walled, and complex profiles, which are ideal for anodizing. Typical tempers include T4 (natural aging) and T6 (for maximum strength), with heat treatment temperatures around 522°C, followed by quenching and aging.

Machinability and Weldability

This alloy demonstrates good machinability using standard tools. Its low alloy content enhances weldability, especially with TIG and MIG processes, although post-weld heat treatment may be required to restore T6 properties in the heat-affected zone.

Comparison of 6063 Aluminum Round Tube with 6061 Aluminum

• Strength: 6061 aluminum has higher strength (tensile strength around 45 ksi), but 6063 aluminum offers better formability.
• Machinability: 6063 aluminum is softer and easier to cut, drill, or weld, whereas 6061 aluminum is better suited for high-stress structural components.
• Aesthetic Applications: 6063 aluminum is preferred in architectural applications due to its superior anodizing results.

6063 aluminum round tubes combine medium strength, high surface quality, corrosion resistance, and extrudability, making them widely used in architectural, mechanical, and industrial fields.

6063 Aluminum Round Tube Advantages and Limitations

• Advantages: Good extrudability, excellent corrosion resistance, outstanding surface treatment performance, and good weldability and formability.
• Limitations: Relatively low strength and poor abrasion resistance.

6063 aluminum alloy round tube is a material suitable for construction, decoration, and lightweight structural applications, especially in environments requiring high surface quality and corrosion resistance.

6063 Aluminum Round Tube Stock List