MG · magnesium
Magnesium Alloy AM50A (die casting, high ductility)
The most ductile of the common die-casting magnesium grades: lower strength than AM60, higher elongation, and it machines like the rest of the family.
Quoting this material
- Typical lead time
- 12–20 working days
- Condition
- As die cast
- Achievable finish
- Ra 1.6 µm typical · Ra 0.4 µm best
Machined in-house to your drawing: see the precision CNC machining service and the machine and inspection capability it runs on.
Machinability
Our own 1–10 shop ranking, not a published index: 10 is free-cutting brass C360, 1 is Inconel 718. It ranks how a material behaves on the floor - cycle time, chip control and tool life together. Where a published index exists it is quoted in the note.
The most ductile of the common die-casting magnesium grades: lower strength than AM60, higher elongation, and it machines like the rest of the family.
Properties as supplied
| Parameter | Value | Unit |
|---|---|---|
| Tensile strength | 200–220 | MPa |
| Yield strength (0.2%) | 110–125 | MPa |
| Elongation | 6–10 | % |
| Hardness | 55–65 | HB |
| Thermal conductivity | 65 | W/m·K |
| Modulus of elasticity | 45 | GPa |
Hardness, tensile and thermal figures are typical published values for the condition stated. Actual mill certificates govern; send the specification with the drawing and we confirm against the certificate before the material is cut.
Condition
As die cast
Heat treatment
Not hardenable by heat treatment. The A designation is the high-purity condition for corrosion resistance, which matters more on magnesium than on any other metal family here.
Achievable surface finish
Ra 1.6 µm
Ra 0.4 µm
Bright machined finish with a conversion coating or anodised layer for protection.
Tooling and cutting parameters
Cutting speed
- 300–700 m/min (sharp uncoated carbide)
Feed
- 0.10–0.35 mm/rev turning · 0.10–0.30 mm/tooth milling
Tooling
- Sharp uncoated carbide with large clearance
Coolant
- Mineral-oil mist or dry
Starting points for carbide on a rigid setup, not a guarantee. The right numbers depend on the machine, the toolholder and the fixturing - ask and we will say what we would actually run.
Typical applications
- Large automotive structural castings
- Instrument panel structures
- Front-end and door modules
- Seat structures
- Energy-absorbing components
DFM notes for this grade
- It is the grade for a large, thin-walled casting that has to bend rather than break: instrument panel structures and door modules are the classic applications
- The lowest strength of the die-casting grades, so the section is designed for stiffness and the material provides the weight saving
- Castability is excellent for thin walls - better than AZ91 on a large complex part, which is why so much automotive magnesium is AM50 or AM60
Questions buyers ask
- Why is AM50A used for large automotive castings?
- It die casts into thin, complex walls with better ductility than the higher-aluminium grades. An instrument panel structure is a big, complex, thin-walled part that has to survive a crash test - that combination of castability and elongation is exactly what it was developed for.
- Does it need the same corrosion protection as other magnesium?
- Yes, and the A or B high-purity designation is what makes the protection system work. Every magnesium casting gets a conversion coating or a paint system, and the purity of the alloy determines how well it holds up if that system is damaged.
Grades we would quote instead
AM60B
8/10The ductile die-casting magnesium: less aluminium than AZ91, so lower strength but far better elongation.
AZ91D
8/10The most common die-casting magnesium: high aluminium content gives good castability and decent strength, and it machines fast with excellent finishes.
AZ31B
9/10Magnesium machines faster than aluminium with a sharper finish, provided the chip is kept moving and the swarf rules are respected.