Aluminium-Silicon Casting Alloys

Aluminium-silicon casting alloys are the workhorse foundry and additive grades for powertrain and structural castings. A356-type alloys dominate gravity and low-pressure cylinder heads, knuckles and subframe nodes; AlSi10Mg is the default powder for laser powder-bed aluminium parts in motorsport and hypercar. Silicon improves fluidity and reduces shrinkage, so complex thin-wall housings, gearbox cases and integrated EV motor housings can be cast or printed that would be impractical in 6xxx wrought stock. Heat treatment (T6 and similar) and hot isostatic pressing for additive parts are part of the usual specification. This is not the wrought 5/6/7xxx family and not Scalmalloy-class aluminium-magnesium-scandium powder. It is the Al-Si casting and additive family behind most aluminium engine, gearbox and printed structural parts in LVHV.