Pure Aluminium, also known as Commercially Pure (CP) Aluminium, contains 99.0% to 99.99% aluminium with minimal alloying additions. Common grades include AA 1050, 1060, 1070, 1080, 1090, and 1100 series.
Due to its extremely high aluminium content, pure aluminium exhibits excellent corrosion resistance, outstanding electrical and thermal conductivity, superior ductility, and ease of fabrication. It is widely used where conductivity, hygiene, and formability are more important than strength.
Chemical & Physical Properties
| Property | Typical Value |
|---|---|
| Purity | 99.0 – 99.99 % |
| Density | ~2.70 g/cm³ |
| Melting Point | ~660 °C |
| Thermal Conductivity | 220–235 W/m·K |
| Electrical Conductivity | 60–62 % IACS |
| Coefficient of Thermal Expansion | ~23 × 10⁻⁶ /°C |
| Reflectivity | Very High |
| Magnetic Property | Non-magnetic |
Mechanical Properties
| Property | Typical Value |
|---|---|
| Tensile Strength | 40 – 90 MPa |
| Yield Strength | 15 – 35 MPa |
| Elongation | 20 – 40 % |
| Brinell Hardness | 15 – 30 HB |
| Elastic Modulus | ~69 GPa |
| Fatigue Strength | Low |
Key Characteristics
✔ Exceptional corrosion resistance via natural Al₂O₃ oxide layer
✔ Excellent electrical and thermal conductivity
✔ Superior formability and deep-drawing performance
✔ Lightweight and non-magnetic
✔ Hygienic, food-safe, and non-toxic
✔ 100% recyclable with low environmental impact
Tempers & Strength Control
Pure aluminium is not heat treatable. Strength is controlled by temper:
✔ O (Annealed) – Maximum ductility
✔ H12 / H14 – Light to medium cold work
✔ H18 – Full hard (limited ductility)
Fabrication & Processing Behavior
Forming: Excellent bending, rolling, stamping, and deep drawing
Welding: Easily weldable (TIG, MIG, resistance welding)
Machining: Soft material – requires sharp tools
Surface Finishing: Anodizing, polishing, brushing, embossing
Available Forms
✔ Sheets & plates
✔ Coils
✔ Foils
✔ Rods & bars
✔ Pipes & tubes
✔ Extrusions
✔ Ingots & billets
✔ Busbars & conductors
Applications
✔ Electrical & power transmission
✔ Packaging (food & pharmaceuticals)
✔ Construction & architecture
✔ Automotive & transportation
✔ HVAC & heat exchangers
✔ Consumer & household products
✔ Chemical & corrosion-resistant equipment
Advantages & Limitations
Advantages:
✔ Excellent corrosion resistance
✔ High conductivity
✔ Superior formability
✔ Lightweight & food safe
Limitations:
⚠ Low mechanical strength
⚠ Poor wear resistance
⚠ Not suitable for high-load structural use
Pure Aluminium vs Aluminium Alloys
| Property | Pure Aluminium | Aluminium Alloys |
|---|---|---|
| Strength | Low | Medium to High |
| Conductivity | Very High | Moderate |
| Formability | Excellent | Moderate |
| Heat Treatable | No | Yes |
| Corrosion Resistance | Excellent | Grade-dependent |
Pure Aluminium is an essential industrial metal where conductivity, corrosion resistance, hygiene, and formability outweigh strength requirements. It plays a critical role in electrical systems, packaging, construction, HVAC, and consumer goods.