Powder metallurgical aluminium foams can be employed as cores in composite castings. In order to improve particular properties of castings aluminium foam parts were surrounded by cast metal. For encasing the foam cores, squeeze casting, high pressure die casting and low pressure die casting were applied. The casting conditions and the interaction between the aluminium foam cores and the incoming cast metal melt were investigated. Foam cores can be protected against infiltration by the cast metal melt, the rough surface leads to mechanical bonding between core and casting. If required, metallic bonding can be achieved by flux treatment of the core.