AlSi10Mg
metalaluminium-silicon alloy (cast grade adapted for AM)
EN AC-43000EN 1706 AlSi10MgA360 (cast equiv.)Aluminium Silicon 10% MagnesiumAl-10Si-0.3Mg
Composition — EN AC-43000 / AMS 7047
| Element | Min % | Max % | Notes |
|---|---|---|---|
| Al | bal. | balance | |
| Si | 9.00 | 11.000 | Near-eutectic — promotes low shrinkage and good LPBF processability |
| Mg | 0.20 | 0.450 | Precipitation hardening agent — forms Mg₂Si on ageing |
| Fe | — | 0.550 | |
| Cu | — | 0.050 | Low Cu maintained to preserve corrosion resistance and weldability |
| Mn | — | 0.450 | |
| Zn | — | 0.100 | |
| Ti | — | 0.150 | |
| Ni | — | 0.050 | |
| Pb | — | 0.050 | |
| Sn | — | 0.050 |
Mechanical & thermal properties — 4 conditions
| Property | LPBF as-built (XY) | LPBF as-built (Z) | LPBF stress-relieved 300°C (XY) | LPBF T6 heat-treated (XY) |
|---|---|---|---|---|
| Elastic modulus | 65–75 GPa | — | — | — |
| Yield strength (0.2%) | 210–270 MPa | 170–230 MPa | 200–255 MPa | 165–215 MPa |
| Ultimate tensile strength | 320–400 MPa | 270–360 MPa | 300–375 MPa | 240–310 MPa |
| Elongation at break | 2.0–7.0 % | 1.0–5.0 % | 3.0–8.0 % | 6.0–13.0 % |
| Hardness (HV) | 110–150 HV10 | 105–140 HV10 | — | 85–115 HV10 |
| Fatigue strength | 70–120 MPa | — | — | 100–160 MPa |
| Density | 2.67 g/cm³ | — | — | — |
| Thermal conductivity | 100.0–150.0 W/m·K | — | — | 145.0–165.0 W/m·K |
| Specific heat | 900 J/(kg·K) | — | — | — |
| CTE | 20.0–22.0 µm/m·K | — | — | — |
| As-built surface Ra | 7.0–18.0 µm | — | — | — |
Values shown as min–max where a spread is reported, otherwise as typical ± unit. Ranges reflect inter-source variation, not single-sample scatter. All values are for AM-processed specimens unless noted.
Engineering considerations
- Always declare post-condition: as-built, stress-relieved (300°C), or T6. As-built and T6 have ~25% different YS — this is not a minor detail.
- T6 temperature is critical: solution anneal below 510°C is incomplete; above 540°C causes incipient melting. Use a calibrated atmosphere furnace.
- Anisotropy in as-built is significant (XY ≫ Z). For thin brackets loaded in the Z direction, T6 post-processing is recommended to equalise properties.
- Laser reflectivity: LPBF requires ~175–350 W laser power for AlSi10Mg, higher than steel due to high Al reflectivity at Nd:YAG wavelength. Green laser (515 nm) LPBF systems offer improved coupling.
- Build plate adhesion: AlSi10Mg typically requires 150–200°C plate preheat and steel base plate with roughened surface (Ra ~3 µm) to prevent delamination.
- Support structures: Al is soft and supports are easy to remove, but remelting at interfaces creates HAZ and potential LOF — minimise internal support contact area.
- Powder storage: aluminium powder is highly reactive with moisture. Use sealed inert containers; monitor O and H content before each build. ATEX explosive atmosphere precautions mandatory.
- Thermal conductivity application note: T6 heat-treated AlSi10Mg has ~20% higher thermal conductivity than as-built — specify T6 for heat sinks to maximise performance.
- Comparison to Scalmalloy: if operating temperature exceeds 100°C or strength >400 MPa is required, consider Scalmalloy (Al-Mg-Sc) — significantly higher cost but much better elevated-temperature retention.
Advantages
- Lowest density of commercial LPBF metals (~2.67 g/cm³) — best specific strength for lightweight applications
- As-built LPBF strength exceeds cast equivalent — ultra-fine Al-Si eutectic provides Hall-Petch-type strengthening
- High thermal conductivity (130–155 W/m·K) — excellent for heat sink and thermal management applications
- T6 heat treatment produces near-isotropic, ductile properties — reduces build direction sensitivity
- Well-established EOS, Renishaw, Trumpf, SLM parameter sets — shortest qualification path of AM aluminium alloys
- Electrical conductivity ~25% IACS — suitable for lightweight electrical hardware
- Good corrosion resistance in marine and mild industrial environments
- Weldable — allows post-AM hybrid fabrication
Limitations
- As-built ductility is low (2–7%) — unsuitable for crash energy absorption without T6 treatment
- T6 heat treatment substantially reduces yield strength (~240 → 190 MPa) — strength advantage over cast partly negated
- Poor elevated-temperature strength — not suitable above 150°C without alloy redesign (see Scalmalloy for high-temp Al AM)
- No precipitation hardening without Mg — cannot reach 7075 or 2024 strength levels; those alloys are much harder to print
- Laser reflectivity of aluminium (~91% at 1064 nm Yb:YAG) requires high-power laser and careful parameter optimisation to avoid porosity
- Hydrogen porosity risk — must carefully control powder moisture content; Al-H system has high hydrogen solubility in melt
- Limited fatigue endurance in as-built condition — surface finish critical; fatigue-critical parts need machining + optional shot-peening
- Z-direction ductility can drop below 2% — orient primary load axis in XY for ductility-critical applications
Typical applications
Lightweight structural brackets and frames (aerospace, automotive)Heat sinks and thermal management components (electronics cooling)Engine and powertrain housingsJigs, fixtures, and tooling insertsUnmanned aerial vehicle (UAV) structural framesThin-wall pressure housings and enclosuresMotorsport suspension and body componentsMedical device housings and instrument handlesHydraulic manifolds and fluid distribution blocksConsumer electronics structural components
Industries
aerospaceautomotivemotorsportindustrialenergyconsumer
Standards & certifications
AMS-7047established
AlSi10Mg LPBF parts for aerospace structural applications — composition, powder spec, and minimum tensile properties
aerospacedefence
As-built and T6 condition requirements. Required by select aerospace OEMs for Al LPBF parts.
ASTM-E8established
Tensile test method — required for acceptance testing of AM AlSi10Mg
aerospaceautomotiveindustrial
ASTM-E466established
Fatigue testing for rotating and cyclic-load applications
aerospaceautomotivemotorsport
Compatible AM processes (2)
Other metal materials
Ti-6Al-4V Grade 5titanium alloy — alpha-beta316L Stainless Steelaustenitic stainless steel17-4PH Stainless Steelmartensitic precipitation-hardening stainless steelAlSi7Mg Aluminium Alloyhypoeutectic Al-Si-Mg precipitation-hardenable aluminium alloyInconel 718nickel superalloy — precipitation-hardenedInconel 625nickel superalloy — solid-solution-strengthenedCoCrMocobalt-chromium alloy (biomedical and aerospace grade)Maraging Steel MS1 (18Ni-300)maraging steel (ultra-high-strength, precipitation-hardened)H13 Tool Steelchromium-molybdenum hot-work tool steel
Related calculators
HT AdvisorStandard stress-relief, solution, and aging cycles for AM metals (Ti-6Al-4V, IN718, 17-4PH, AlSi10Mg, 316L, CuCrZr) per AMS, ASTM F3301, and AMS 5664.DistortionEstimate residual stress and distortion risk index (σ/σ_y) for LPBF and DED builds. Mercelis-Kruth model with preheat sensitivity table.VEDCompute LPBF VED from power, scan speed, hatch, and layer thickness. Includes process windows for common alloys.Melt PoolLPBF / DED melt pool depth, width, and cooling rate from the Rosenthal moving heat source solution. Absorptivity, thermal diffusivity, and solidification velocity.
Last reviewed: 2026-05-04 · v1 · Sources: AMS-7047, eos-alsi10mg-2023, renishaw-alsi10mg-2023, brandl-2012-alsi10mg, kempen-2012-alsi10mg, tradowsky-2016-alsi10mg, debroy-2018-review, yadollahi-2017-fatigue, ASTM-E8, ASTM-E466