AlSi10Mg (EN AC-43400)

It is an Al-Si-Mg casting alloy with a primary aluminum base and low iron, containing about 10% silicon. Its high fluidity and excellent pressure tightness make it ideal for thin-wall parts and complex geometries: transmission housings, pump bodies, structural brackets and intake manifolds in automotive; valve bodies and hydraulic manifolds; and electric motor housings in industry. It is also the dominant alloy in metal additive manufacturing (3D printing, SLM/DMLS).

The balance is aluminum, with 9.0–11.0% silicon that provides the fluidity to fill thin walls, and 0.20–0.50% magnesium that enables precipitation hardening in the T6 treatment. Iron is kept low (≤0.55% per the EN standard, and ≤0.15% with our primary aluminum base) to maximize ductility; copper is limited to ≤0.10%, along with manganese ≤0.35%, zinc ≤0.10% and titanium ≤0.15%.

Yes. Thanks to its magnesium content it responds to T6 heat treatment, and the low iron of the primary base improves that response. In the T6 condition it reaches a tensile strength (UTS) of 290–330 MPa and a yield strength of 220–280 MPa, with an elongation of 2–5% and hardness near 80 HB. This places it among the higher-performing Al-Si-Mg casting alloys.

It is compatible with gravity casting, permanent mold, and sand casting, where its high fluidity eases the filling of thin walls. It is also the dominant alloy in metal additive manufacturing (SLM/DMLS). For high-volume high-pressure die casting (HPDC), where higher iron content is tolerated, we recommend the A360 version (AA standard 360.0/A360.0).

Both belong to the AlSi10Mg family (EN AC-43400) but are optimized for different processes. This primary-based AlSi10Mg keeps iron very low (≤0.15%) to maximize ductility and T6 response, and is intended for gravity casting, permanent mold and additive manufacturing. A360 is the die-casting (HPDC) variant: it allows higher iron (≤1.3% in A360.0) to resist die soldering and is produced in high volume.

It offers good corrosion resistance in industrial environments, aided by its low copper content (≤0.10%), a typical trait of Al-Si alloys. Its high fluidity and low tendency to microporosity give it excellent pressure tightness, which is why it is widely used in valve bodies, hydraulic manifolds and sealed components that must contain fluids without leaking.

The low-iron AlSi10Mg (EN AC-43400) requires a primary aluminum base to keep iron at ≤0.15%, which preserves its ductility and T6 heat-treatment response. For that reason we manufacture it from clean primary aluminum, not from higher-iron secondary scrap. If your application is high-pressure die casting (HPDC) and tolerates higher iron, the A360 variant can indeed be produced from secondary aluminum.