Aluminium Alloy | Commercial Alloy
5251 - H22 Sheet and Plate
Aluminium alloy 5251 is a medium strength alloy possessing good ductility and therefore good formability. Alloy 5251 is known for work hardening rapidly and is readily weldable. It also possesses high corrosion resistance particularly in marine environments.
Applications
5251 is typically used in:
~ Boats
~ Panelling and pressings
~ Marine structures
~ Aircraft parts
~ Vehicle panels
~ Furniture tubing
~ Silos
~ Containers
Mechanical Properties shown are for H22 condition - Mechanical properties for other tempers are shown on page 2.
Chemical Composition
|
BS EN573-3:2009 Alloy 5251 |
|
|---|---|
| Chemical Element | % Present |
| Aluminium (Al) | balance |
| Other (Each) | 0.05 max |
| Copper (Cu) | 0.15 max |
| Zinc (Zn) | 0.15 max |
| Chromium (Cr) | 0.15 max |
| Titanium (Ti) | 0.15 max |
| Others (Total) | 0.15 max |
| Silicon (Si) | 0.4 max |
| Manganese (Mn) | 0.1 - 0.5 |
| Iron (Fe) | 0.5 max |
| Magnesium (Mg) | 1.7 - 2.4 |
Alloy Designations
Alloy 5251 corresponds to the following standard designations and specifications, although may not be a direct equivalent:
Al Mg2
Al 2.0Mg 0.3Mn
Temper Types
The most common tempers for 5251 aluminium are:
- H24
- H26
- O
- H22
Supplied Forms
- Plate
- Sheet
Generic Physical Properties
| Physical Property | Value |
|---|---|
| Density | 2.69 g/cm³ |
| Melting Point | 625 °C |
| Thermal Expansion | 25 x10^-6 /K |
| Modulus of Elasticity | 70 GPa |
| Thermal Conductivity | 134 W/m.K |
| Electrical Resistivity | 0.044 x10^-6 Ω .m |
Mechanical Properties
|
BS EN 485-2:2008 Sheet and Plate - 0.2mm to 25mm |
|
|---|---|
| Mechanical Property | Value |
| Proof Stress | 120 Min MPa |
| Tensile Strength | 190 - 230 MPa |
| Hardness Brinell | 56 HB |
Properties above are for material in the H22 condition
Weldability
Aluminium alloy 5251 is a readily weldable alloy.
The recommended filler wire is 5356 when welding alloy 5251 to itself, 6XXX series alloys, 7XXX series alloys and most other 5XXX alloys.
When welding alloy 5251 to 5005, 5020, 1XXX series or 3XXX series alloys, the recommended filler wire is 4043.
Weldability – Gas: Very Good
Weldability – Arc: Very Good
Weldability – Resistance: Very Good
Brazability: Poor
Fabrication
Workability – Cold: Very Good
Machinability: Average