Fabrication and squeeze casting infiltration of graphite/alumina preforms

The manufacturing of a suitable rigid porous graphite/alumina preform has been investigated taking into account the influence of the binder type, the graphite/alumina content in the preform and the percentage of binder in water. The preforms showing an acceptable rigidity have been infiltrated with a CuSn12 bronze alloy by squeeze casting considering two different pouring temperatures. The composite quality is strongly influenced by both the graphite/alumina volume fractions and the binder type. The optimal quality has been obtained by infiltrating a Carsil 2000 binded preform containing 30 vol% graphite flakes and 70 vol% alumina fibres.