Scalmalloy Aluminum
An Al-Mg-Sc-Zr alloy for laser metal printing
Typical values for the temper in the title
Scalmalloy is an aluminum-magnesium alloy with scandium and zirconium, developed specifically for metal powder 3D printing (Laser Powder Bed Fusion). Scandium and zirconium form tiny particles that strengthen and keep the grains fine, even in the fast solidification of printing.
After a simple heat treatment it reaches a tensile strength of about 530 MPa, far above common printing alloys such as AlSi10Mg, with good ductility. It is used for topology-optimized parts in aerospace, space and motorsport.
Mechanical and physical properties
| Property | Value | Note |
|---|---|---|
| Tensile strength Rm | 530 MPa | |
| Yield strength Rp0.2 | 490 MPa | |
| Elongation A | 13% | |
| Hardness | 150 HB | |
| Modulus of elasticity E | 74 GPa | |
| Density ρ | 2.67 g/cm³ | |
| Machinability | 20% — AM only | relative rating in the site database |
Chemical composition (wt %)
| Element | Range | Role |
|---|---|---|
| Mg magnesium | about 4.5 (nominal) | solid-solution strengthening |
| Sc scandium | about 0.7 (nominal) | strengthening particles and fine grains |
| Mn manganese | about 0.5 (nominal) | |
| Zr zirconium | about 0.3 (nominal) | strengthening particles, with scandium |
| Al aluminum | balance |
Common tempers
Scalmalloy is printed and then given a simple heat treatment (aging), without solution treatment.
| Temper | Properties | When to choose it |
|---|---|---|
| As printed | lower strength | before heat treatment |
| After aging | Rm ≈ 530 MPa, Rp0.2 ≈ 490 MPa (database value) | the service condition |
Applications
- Topology-optimized aerospace parts
- Light brackets and holders
- Motorsport parts
- Space components
- Prototypes and particularly light parts
Fabrication
Printing
Intended for laser powder bed printing. It is less prone to cracking in this process than other strong aluminum alloys.
Heat treatment
Aging only, without solution treatment, so less distortion.
Cost
Scandium is expensive, and the powder costs far more than ordinary aluminum powders.
Compared with similar materials
| Material | Rm / Rp0.2 | Welding | When it is the better choice |
|---|---|---|---|
| 7075-T6 | 503–572 / 434–503 MPa | Not recommended — FSW | a wrought material of similar strength, not suited to printing · material page |
| 5083-H111 | 275–350 / 125–200 MPa | Excellent — ER5356 | a wrought Al-Mg alloy, without scandium · material page |
| 6061-T6 | 310 / 276 MPa | Good — ER4043 | a general wrought material · material page |
Common mistakes
Trying to print 7075 instead
7xxx alloys crack in printing. For high strength in printing, Scalmalloy.
Designing a simple part for printing
The advantage is in complex geometry. A simple part is cheaper to machine.
Skipping the heat treatment
Full strength comes only after aging.
Equivalents, standards and supply
| APW | Scalmalloy |
|---|---|
| Standards | Producer's specification (APWorks) |
| Forms | AM powder only |
| Producers | APWorks (Airbus) · Heraeus |
Learn more
Values are typical and for comparison only. For design, rely on the standard and on the mill certificate. Sources: Aluminum Association (composition), ASM and MatWeb data sheets, and the METAL HUB materials database.
Updated: October 31, 2026