6063 Aluminum Round Bar

6063 aluminum round bar is a wrought aluminum alloy material in the Al-Mg-Si series, with magnesium (Mg) and silicon (Si) as its primary alloying elements. It is a heat-treatable strengthening alloy that possesses excellent comprehensive properties.

6063 aluminum round bar is a widely used extruded product, highly praised for its balance of formability, corrosion resistance, and surface finish. The following is a brief overview of its chemical composition, properties, manufacturing process, treatment methods, applications, and standards.

The extruded surface of 6063 round bar is smooth, with moderate strength and excellent anodizing response. Common tempers include T5, T52, and T6. Standard dimensions range from 1/4 inch to 6 inches in diameter, with dimensional tolerances up to ±0.008 inch. Specifications conform to ASTM B221 and AMS QQ-A-200/9 standards.

6063 aluminum round bar belongs to the 6xxx series, primarily composed of magnesium and silicon. Through optimization, it can be extruded into complex shapes with excellent surface quality. Typical tempers for bars include T5 (cooled after high-temperature forming and then artificially aged), T52 (an improved version of T5 with special strength/toughness), and T6 (solution heat-treated and then artificially aged).

6063 Aluminum Round Bar Chemical Composition

The nominal composition of 6063 aluminum is:

• Magnesium (Mg): 0.45 – 0.90 wt %
• Silicon (Si): 0.20 – 0.60 wt %
• Iron (Fe): ≤ 0.35 wt %
• Copper (Cu): ≤ 0.10 wt %
• Manganese (Mn): ≤ 0.10 wt %
• Chromium (Cr): ≤ 0.10 wt %
• Titanium (Ti): ≤ 0.10 wt %
• Zinc (Zn): ≤ 0.10 wt %
• Others (each): ≤ 0.05 wt % (total ≤ 0.15 wt %)
• Remainder: Aluminum (Al).

6063 Aluminum Round Bar Mechanical Properties

Typical properties vary by temper:

6063 Aluminum Round Bar Physical and Thermal Properties

• Density: 2.69 g/cm³ (0.098 lb/in³)
• Melting Range: 615 °C (1, 139 °F)
• Thermal Conductivity: 201–218 W/m·K
• Coefficient of Thermal Expansion: ~23.5 × 10⁻⁶ /K
• Modulus of Elasticity: ~69 GPa (10, 000 ksi)
• Electrical Resistivity: ~0.035 × 10⁻⁶ Ω·m
• Specific Heat Capacity: ~900 J/kg·K

6063 Aluminum Round Bar Tempers and Heat Treatment

6063 aluminum is typically available in T5, T52, and T6 tempers:

• T6 Temper: Undergoes solution heat treatment followed by artificial aging, resulting in approximately 30% higher strength compared to untreated temper.
• T5/T52: Naturally aged after extrusion, providing moderate strength and better formability.

6063 Aluminum Round Bar Dimensions and Tolerances

Diameter range: 3 mm (0.1 inch) to 600 mm (24 inches), with standard lengths from 1 to 12 meters (custom cutting available).

Tolerances:

• Diameter: ±0.002 inches for precision applications.
• Straightness: 0.013 inches per foot.

6063 Aluminum Round Bar Surface Treatments

• Surface finishes: Bright, polished, anodized (silver, black, bronze), brushed, or sandblasted.
• Anodizing: 6063 is highly responsive, forming a uniform oxide layer ideal for decorative and protective surface treatments; commonly uses Type II anodizing or hardcoat Type III anodizing.
• Powder coating and painting: Pre-treatment with chromate conversion enhances adhesion and durability.
• Mechanical surface processing: Prior to coating, customizable textures can be achieved through polishing, grinding, or shot blasting.

6063 Aluminum Round Bar Standards and Specifications

ASTM B221 — "Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes."

AMS QQ-A-200/9 and AMS 4156 — Aerospace material specifications for 6063 extruded profiles.

BS EN 755-2 — European extrusion tolerance and performance standards (applicable for profiles with maximum Ø150 mm).

Surface tolerance (extruded):

• Ø 0.250–0.499 inches: ± 0.008 inches
• Ø 0.500–0.749 inches: ± 0.009 inches

6063 Aluminum Round Bar Standards and Equivalent Standards

Standards: ASTM B221, AMS 4156, ASME SB221, EN AW-6063, DIN AlMgSi0.5.

International equivalent standards:

• UNS A96063 (USA)
• EN AW-6063 (Europe)
• AlMg0.7Si (ISO)

6063 Aluminum Round Bar Applications

Due to its various characteristics, 6063 round bar can be used in:

• Architecture: Window frames, railings, signage, decorative trims.
• Marine: Fittings, railings, light structural components.
• Furniture and fixtures: Legs, brackets, and tubing in modular furniture.
• Heat sinks and electrical: Bus bars, connectors, small heat-dissipating profiles.
• Piping and tubing: Fluid transport applications where corrosion resistance and appearance are critical.

6063 Aluminum Round Bar Manufacturing and Processing Properties

• Extrudability: Excellent, capable of thin-wall and complex shapes, with smooth surfaces.
• Machinability: Supports cutting, welding, forging, and extrusion into complex shapes; compatible with standard dies but may require lower feed speeds.
• Weldability: Suitable for gas welding, arc welding, and resistance welding; proper filler use can maintain joint strength during fusion processes.
• Heat Treatment: Solution treatment (~525°C), quenching, and artificial aging (~175°C) are used for T6 temper to optimize mechanical properties.
• Brazing/Soldering: Good; anodized surfaces may need to be cleaned to ensure brazing quality.
• ‌Excellent hot formability‌: Suitable for high-speed extrusion or forging of complex thin-walled and hollow structures, ideal for precision profile processing.
• ‌Outstanding surface treatment performance‌: Excellent anodizing and coloring performance, with high surface finish after processing.

HC 6063 Aluminum Round Bar Availability and Sizes

Stock diameter ranges from 6 mm (1/4 inch) to 150 mm (6 inches), with standard lengths from 1 foot to 20 feet (300 mm to 6 meters); custom cut-to-length service available. Custom diameters and lengths are also widely offered, and delivery times depend on extrusion dies.

6063 aluminum round bar combines excellent corrosion resistance, good formability, and attractive surface treatment, making it a preferred alloy for architectural, marine, and electrical applications. Its balanced mechanical and thermal properties, along with broad specification coverage (ASTM B221, AMS QQ-A-200/9), ensure consistency and reliability across various projects.

6063 Aluminum Round Bar Stock List