6063 Extruded Aluminum Bar

1. Material Composition & Manufacturing Process

6063 aluminum alloy (AlMgSi0.5) is a medium-strength alloy with excellent extrudability, surface finish, and corrosion resistance. This popular architectural alloy combines good mechanical properties with superior formability and anodizing response:

• Primary Alloying Elements:
  • Magnesium (Mg): 0.45-0.90% (precipitation hardening)
  • Silicon (Si): 0.20-0.60% (forms Mg₂Si strengthening precipitates)
• Base Material:
  • Aluminum (Al): ≥98.0% (balance)
• Controlled Impurities:
  • Iron (Fe): ≤0.35% max
  • Copper (Cu): ≤0.10% max
  • Manganese (Mn): ≤0.10% max
  • Chromium (Cr): ≤0.10% max
  • Zinc (Zn): ≤0.10% max
  • Titanium (Ti): ≤0.10% max
  • Other elements: ≤0.05% each, ≤0.15% total

Premium Extrusion Manufacturing Process:

1. Billet Preparation:
   1. High-purity primary aluminum (99.7% minimum)
   1. Precise alloying element additions
   1. Degassing treatment (hydrogen < 0.2 ml/100g)
   1. Direct-chill (DC) semi-continuous casting
   1. Homogenization at 560-580°C for 4-8 hours
2. Billet Preheating:
   1. Computer-controlled heating to 450-480°C
   1. Temperature uniformity: ±5°C
   1. Oxide layer removal (scalping)
3. Extrusion:
   1. Breakthrough pressure: 35-45 MPa
   1. Running pressure: 20-35 MPa
   1. Ram speed: 5-15 mm/sec (profile-dependent)
   1. Exit temperature control: 510-540°C
   1. Die temperature: 480-500°C
4. Cooling:
   1. Air cooling or water quenching (temper-dependent)
   1. Controlled cooling rate for optimal properties
   1. Maximum distortion control
5. Stretching:
   1. 0.5-2.0% permanent deformation
   1. Straightening and stress relief
6. Artificial Aging (T5/T6):
   1. T5: 175-185°C for 2-4 hours
   1. T6: Solution heat treatment (520-530°C) + Artificial aging (175-185°C for 6-8 hours)
7. Finishing Operations:
   1. Cut-to-length precision: ±1mm
   1. Surface finish enhancement
   1. Final straightness check and correction

All manufacturing maintains digital process monitoring for complete traceability.

2. Mechanical Properties of 6063 Extruded Bar

Property	T5 (min)	T5 (typical)	T6 (min)	T6 (typical)	Test Method
Ultimate Tensile Strength	150 MPa	160-185 MPa	205 MPa	215-230 MPa	ASTM E8
Yield Strength (0.2%)	110 MPa	120-145 MPa	170 MPa	180-200 MPa	ASTM E8
Elongation (2 inch)	8%	10-14%	8%	10-12%	ASTM E8
Hardness (Brinell)	60 HB	65-75 HB	75 HB	80-90 HB	ASTM E10
Fatigue Strength (5×10⁸)	70 MPa	75-85 MPa	95 MPa	100-110 MPa	ASTM E466
Shear Strength	90 MPa	95-110 MPa	120 MPa	125-140 MPa	ASTM B769
Modulus of Elasticity	69.5 GPa	69.5 GPa	69.5 GPa	69.5 GPa	ASTM E111

Property Distribution:

• Longitudinal to transverse property ratio: 1.00:0.95
• Wall thickness effect: <5% variation for up to 10mm thickness
• Corner to flat section property variation: <10%
• Surface to core hardness variation: <5 HB

3. Surface Finish & Appearance

Surface Quality Classifications:

1. Architectural Grade (AA10):
   1. Ra ≤ 0.4μm surface roughness
   1. No visible defects at 1m viewing distance
   1. Suitable for decorative anodizing
   1. Consistent color after anodizing
2. Commercial Grade (AA20):
   1. Ra ≤ 0.8μm surface roughness
   1. Minor defects acceptable at >2m viewing distance
   1. Good anodizing response
3. Industrial Grade (AA30):
   1. Ra ≤ 1.6μm surface roughness
   1. Functional applications where appearance is secondary

Surface Treatment Compatibility:

• Anodizing Response: Excellent
  • Type II (sulfuric acid): 5-25μm thickness
  • Type III (hard coat): 25-75μm thickness
  • Color consistency rating: Excellent
  • Architectural Class I: 18μm minimum coating
  • Architectural Class II: 10μm minimum coating
• Mechanical Finishing:
  • Brushing/Polishing: Excellent response
  • Bead blasting: Uniform matte finish
  • Bright dipping: High reflectivity achievable
• Painting/Coating:
  • Powder coating adhesion: Excellent
  • Wet paint compatibility: Good with proper pretreatment
  • Chromate conversion coating: Class 1A achievable

4. Dimensional Specifications & Tolerances

Parameter	Standard Range	Precision Tolerance	Commercial Tolerance	Test Method
Diameter (Round)	5-300 mm	±0.15mm up to 30mm	±0.25mm up to 30mm	Micrometer
		±0.3% above 30mm	±0.5% above 30mm
Width (Rectangle)	10-200 mm	±0.15mm up to 50mm	±0.25mm up to 50mm	Caliper
		±0.3% above 50mm	±0.5% above 50mm
Length	1000-6500 mm	±2mm	±5mm	Tape measure
Straightness	N/A	0.3mm/m	0.5mm/m	Straightedge
Twist (Rectangular)	N/A	1° max per meter	3° max per meter	Protractor
Corner Radius	N/A	±0.2mm	±0.5mm	Radius gauge

Standard Available Forms:

• Round Bar: Diameters 5-300mm
• Hexagonal Bar: Across flats 8-75mm
• Square Bar: Side dimensions 5-150mm
• Rectangular Bar: Width up to 200mm, thickness from 3mm
• Custom profiles available with appropriate tooling

5. Temper Designations & Heat Treatment Options

Temper Code	Process Description	Optimal Applications	Key Characteristics
T1	Cooled from extrusion and naturally aged	Non-critical applications	Moderate strength, excellent formability
T4	Solution heat treated and naturally aged	Forming applications	Good formability, moderate strength
T5	Cooled from extrusion and artificially aged	General purpose	Good strength, excellent extrudability
T6	Solution heat treated and artificially aged	Structural applications	Maximum strength and hardness
T52	Cooled from extrusion, stress relieved, artificially aged	Length-critical applications	Improved straightness, good strength
T83	Solution heat treated, cold worked, artificially aged	High-stress applications	Enhanced strength with good toughness

Temper Selection Guidance:

• T5: Most economical for standard applications
• T6: When maximum strength is required
• T4: When post-extrusion forming is needed
• T52: For applications requiring strict dimensional stability

6. Machining & Fabrication Characteristics

Operation	Tool Material	Recommended Parameters	Comments
Turning	HSS, Carbide	Vc=200-500 m/min, f=0.1-0.4 mm/rev	Excellent surface finish
Drilling	HSS, Carbide	Vc=80-150 m/min, f=0.15-0.3 mm/rev	Low cutting forces
Milling	HSS, Carbide	Vc=200-600 m/min, fz=0.1-0.25 mm	Excellent chip evacuation
Tapping	HSS, TiN coated	Vc=10-30 m/min	Excellent thread quality
Sawing	Carbide tipped	Vc=800-1500 m/min, medium pitch	Clean cuts with minimal burr
Threading	HSS, Carbide	Vc=150-300 m/min, fine feed	Excellent thread finish

Fabrication Guidance:

• Machinability Rating: 90% (1100 aluminum = 100%)
• Surface Finish: Excellent (Ra 0.5-1.6μm easily achievable)
• Chip Formation: Short chips with proper tooling
• Coolant: Water-soluble emulsion or minimal lubrication
• Tool Wear: Minimal with proper parameters
• Formability: Excellent in T1/T4 conditions
• Bendability: Minimum radius = 1× thickness (T1/T4), 2× thickness (T6)
• Weldability: Good with TIG/MIG methods
• Thread Rolling: Excellent results in T4 condition

7. Corrosion Resistance & Protection Systems

Environment Type	Resistance Rating	Protection Method	Expected Performance
Rural/Urban Atmosphere	Excellent	Mill finish or anodizing	15-20+ years
Industrial Atmosphere	Very Good	Anodizing Class I	10-15 years
Marine Environment	Good	Anodizing + sealing	5-10 years with maintenance
High Humidity	Excellent	Standard anodizing	10-15 years
Chemical Exposure	Moderate	Hard anodizing + sealing	Application specific
UV Exposure	Excellent	Clear anodizing	No degradation

Surface Protection Options:

• Anodizing:
  • Clear (natural): Excellent clarity and transparency
  • Color anodizing: Consistent color development
  • Hard anodizing: Superior wear resistance
  • Sealing options: Hot water, nickel acetate, PTFE
• Conversion Coatings:
  • Chromate per MIL-DTL-5541
  • Non-chromium alternatives
• Mechanical Finishing:
  • Brushed finish: Uniform directional pattern
  • Polished finish: Mirror-like appearance achievable
  • Sandblasted: Consistent matte texture
• Organic Coatings:
  • Powder coating: Excellent adhesion and durability
  • Liquid paint: Good with proper pretreatment
  • Clear protective coatings: UV and abrasion protection

8. Physical Properties for Engineering Design

Property	Value	Design Consideration
Density	2.70 g/cm³	Weight calculation for components
Melting Range	615-655°C	Thermal processing limitations
Thermal Conductivity	200-220 W/m·K	Heat sink applications
Electrical Conductivity	50-55% IACS	Electrical applications
Specific Heat	900 J/kg·K	Thermal mass calculations
Thermal Expansion (CTE)	23.4 ×10⁻⁶/K	Thermal expansion allowances
Young’s Modulus	69.5 GPa	Structural calculations
Poisson’s Ratio	0.33	Structural analysis parameter
Reflectivity	80-85% (polished)	Optical/lighting applications

Design Considerations:

• Operating Temperature Range: -80°C to +175°C
• Property Retention: Excellent below 100°C
• Electrical Conductivity: Higher than many aluminum alloys
• Magnetic Properties: Non-magnetic
• Recyclability: 100% recyclable, high scrap value
• Environmental Impact: Low carbon footprint compared to steel

9. Quality Assurance & Testing

Standard Testing Procedures:

1. Chemical Composition:
   1. Optical emission spectroscopy
   1. Verification of all major elements and impurities
2. Mechanical Testing:
   1. Tensile testing (longitudinal)
   1. Hardness testing (Webster/Brinell)
3. Dimensional Inspection:
   1. Diameter/dimensions at multiple locations
   1. Straightness verification
   1. Surface finish measurement
4. Visual Inspection:
   1. Surface defects assessment
   1. Die line evaluation
   1. Surface appearance uniformity
5. Specialized Testing (When Required):
   1. Anodizing response test
   1. Grain structure evaluation
   1. Conductivity testing

Standard Certifications:

• Mill Test Report per EN 10204 2.1/3.1
• Chemical analysis certification
• Mechanical properties certification
• Dimensional inspection report
• Heat treatment certification (for T6 temper)

10. Applications & Design Considerations

Primary Applications:

• Architectural components:
  • Window and door frames
  • Curtain wall systems
  • Railings and balustrades
  • Decorative trim and moldings
• Transportation:
  • Automotive trim and components
  • RV and trailer components
  • Bicycle frames and components
• Electrical:
  • Heat sinks and thermal management
  • Electrical enclosures and housings
  • LED lighting fixtures and profiles
• Consumer goods:
  • Furniture components
  • Appliance trim and parts
  • Shower enclosures and bathroom accessories
• Industrial components:
  • Pneumatic cylinder tubes
  • Machine guards and frames
  • Conveyors and material handling

Design Advantages:

• Excellent surface finish for aesthetic applications
• Superior extrudability for complex profiles
• Good strength-to-weight ratio
• Excellent corrosion resistance
• Outstanding anodizing response
• Ease of fabrication and joining
• Cost-effective compared to higher-strength alloys
• Consistent properties and quality
• Readily available in diverse shapes and sizes
• Sustainable material with high recycled content potential

Design Limitations:

• Lower strength compared to 6061/6082 alloys
• Not recommended for highly stressed structural applications
• Limited weldability compared to 6061
• Reduced mechanical properties in weld heat-affected zones
• Temperature limitations above 175°C

Economic Considerations:

• Excellent balance of cost and performance
• Lower processing costs than higher-strength alloys
• Reduced machining costs due to excellent machinability
• Long service life with minimal maintenance
• High scrap value at end of life cycle