6063
The most extruded alloy in the world, preferred for its superior surface finish and excellent anodizing response.
6063 is the most commonly extruded aluminum alloy in the world, known as "architectural aluminum." It offers the best combination of extrudability, surface finish, and corrosion resistance in the 6xxx series.
International Nomenclature
| Standard | Designation |
|---|---|
| AA (USA) | 6063 |
| EN (Europa) | EN AW-6063 · AlMg0.7Si |
| DIN (Alemania) | AlMgSi0.5 / 3.3206 |
| ISO | AlMg0.7Si |
| JIS (Japón) | A6063 |
| BS (Reino Unido) | H9 |
Chemical Composition
| Element | Symbol | Percentage |
|---|---|---|
| Aluminum | Al | Balance |
| Silicon | Si | 0.20–0.60% |
| Magnesium | Mg | 0.45–0.90% |
| Iron | Fe | ≤0.35% |
| Copper | Cu | ≤0.10% |
| Manganese | Mn | ≤0.10% |
| Chromium | Cr | ≤0.10% |
| Zinc | Zn | ≤0.10% |
| Titanium | Ti | ≤0.10% |
Physical Properties
| Property | Value |
|---|---|
| Density | 2.70 g/cm³ |
| Melting Range | 616–654 °C |
| Thermal Conductivity | 200 W/m·K |
| Electrical Conductivity | ~53% IACS |
Mechanical Properties
| Property | Value |
|---|---|
| Tensile Strength (UTS) | 190–240 MPa (T6) |
| Yield Strength | 160–214 MPa (T6) |
| Elongation | 8–12% |
| Hardness | ~73 HB |
Key Characteristics
- The most commonly extruded aluminum alloy in the world
- Excellent anodizing response producing smooth, attractive finishes
- Superior corrosion resistance vs. 6061 (lower copper content)
- Excellent formability and extrudability into complex cross-sections
- Self-healing Al₂O₃ protective oxide layer
Compared to Similar Alloys
6061 vs 6063
Both are heat-treatable 6xxx (AlMgSi) alloys, but 6061 carries more magnesium (0.80–1.20%) and intentional copper (0.15–0.40%) for higher structural strength, while 6063 keeps copper near-zero (≤0.10%) with less magnesium, prioritizing surface finish and anodizing. In short: 6061 is the structural benchmark; 6063 is the "architectural aluminum" for visible extrusions.
| Dimension | 6061 | 6063 |
|---|---|---|
| Key alloying elements | Mg 0.80–1.20%, Si 0.40–0.80%, intentional Cu 0.15–0.40% | Mg 0.45–0.90%, Si 0.20–0.60%, Cu ≤0.10% (near-zero) |
| Strength (T6) | UTS 290–310 MPa, yield 240–276 MPa, ~95 HB | UTS 190–240 MPa, yield 160–214 MPa, ~73 HB |
| Anodizing & finish | Good, but copper slightly dulls the anodized finish | Excellent (★★★★★); smooth finishes thanks to low copper |
| Corrosion resistance | Good in atmosphere and seawater; slightly lower due to copper | Superior to 6061 thanks to its lower copper content |
| Extrudability / forming | 2nd most-extruded alloy; excellent machinability (T4/T6) | World's most-extruded alloy; complex, thin cross-sections |
| Electrical conductivity | ~43% IACS; thermal conductivity 152 W/m·K | ~53% IACS; thermal conductivity 200 W/m·K |
| Typical application | Structural: automotive, aerospace, marine, bridges | Architecture: frames, curtain walls, railings, tubing |
6061: Choose 6061 when you need the highest structural strength and hardness (UTS ~290–310 MPa, ~95 HB) for load-bearing parts in transportation, marine, or construction.
6063: Choose 6063 when surface appearance and anodizing matter, or for architectural extrusions with complex cross-sections and superior corrosion resistance.
Industries & Applications
Architecture
Window/door frames, curtain walls, storefronts, sign frames
Construction
Railings, balustrading, shop fittings, structural trim
Piping/Tubing
Irrigation systems, HVAC ducting, fluid transport
Transportation
Truck frames, trailer floors, bus structures
Special Notes
6063 is the default alloy when surface appearance matters. Its low copper content is the key reason for its better anodizing response compared to 6061. We manufacture bars and ingots optimized for extruders.
Frequently Asked Questions
What is alloy 6063 and what is it used for?
6063 is the most extruded aluminum alloy in the world, known as "architectural aluminum." It is used mainly for window and door frames, curtain walls, storefronts, railings and trim, as well as irrigation piping, HVAC ducting and transport structures. It offers the best combination of extrudability, surface finish and corrosion resistance in the 6xxx series.
What are the alloying elements of 6063 and what do they do?
6063 is an Al-Mg-Si alloy with magnesium (0.45–0.90%) and silicon (0.20–0.60%) as its main elements; together they form Mg₂Si precipitates that provide strength through heat treatment. Copper is kept very low (≤0.10%), which is key to its excellent anodizing response and corrosion resistance. Iron, manganese, chromium, zinc and titanium are held to ≤0.35% or less as controlled impurities.
Is 6063 heat-treatable and what strength does it reach in the T6 temper?
Yes, 6063 is a heat-treatable 6xxx-series alloy that hardens by precipitation of Mg₂Si. In the T6 temper it reaches a tensile strength of 190–240 MPa, a yield strength of 160–214 MPa, elongation of 8–12% and a hardness of about 73 HB. This places it below 6061, prioritizing finish and extrudability over maximum strength.
Why does 6063 anodize better than 6061?
The key reason is its low copper content (≤0.10% in 6063 versus 0.15–0.40% in 6061). Lower copper produces smooth, clear and attractive anodized finishes without the discoloration copper tends to cause. This is why 6063 is the default alloy when surface appearance matters, and it also offers superior corrosion resistance thanks to its self-healing Al₂O₃ oxide layer.
How does 6063 differ from 6061?
Both are extruded Al-Mg-Si alloys, but 6061 has more copper (0.15–0.40%) and more magnesium (0.80–1.20%), giving it higher strength: in T6 it reaches 290–310 MPa tensile versus 190–240 MPa for 6063. 6063 prioritizes extrudability, surface finish and anodizing; 6061 is the high-strength structural choice. 6063 also offers higher electrical conductivity (~53% IACS vs. ~43% IACS).
Is 6063 a good choice for electrical conduction?
Yes. 6063 offers an electrical conductivity of ~53% IACS and a thermal conductivity of 200 W/m·K, notably high values for a heat-treatable 6xxx-series alloy. That combination of conductivity with moderate strength makes it suitable for conductor profiles and applications where heat dissipation is needed alongside light structural loading.
Does Transformación Puebla manufacture 6063 and in what form?
Yes. We manufacture 6063 as bars and ingots optimized for extruders, starting from primary and recycled aluminum to achieve the controlled composition the 6xxx series requires. As it is the default alloy when surface appearance matters, we pay particular attention to the low copper content to guarantee its characteristic anodizing response.
Need 6063?
We manufacture this alloy in ingots, donuts, and bars to your exact specifications.