The aluminium die casting process is always limited when it comes to casting free-form channels with curves or undercuts, because the mould core cannot be retracted from the part. The Core Free casting process for aluminium was developed and patented by Rubitech to overcome this limitation, even adding the possibility to cast a closed hollow.

 

Our concept

The Core Free casting has two cast-in aluminium shells which together act as a hollow core inserted in the mould. In turn, the two shells are die cast, which allows a free-form and accurate geometry of the core. Because the hollow core is cast in the same basic material, there is no need to remove it from the final casting. The hollow core remains locked inside as an integral part of the final casting and is only noticeable as a parting line inside the channel. The resulting wall thickness in the cored area is around twice that of standard die casting, in the same range as sand casting or gravity casting.  In non-cored areas the wall thickness can be lower. The specially shaped shells are based upon your 3D casting model. To ensure the hollow core remains correctly positioned and is not destroyed during casting we take special care in designing the shells and moulds.

 

Free form flexibility combined with the benefits of die casting

Core Free Casting offers interesting opportunities compared to sand casting or gravity casting: