Porous ceramic preforms for reinforcing of composite materials based on copper or aluminium alloys were produced. Alumina Saffil fibres were mixed with water solution of silica binder, dried  and  formed to required shape. Then the firing at 950C was applied in order to produce preforms characterised by the good durability, high temperature resistance and open porosity for the infiltration  with the liquid metal under high pressure.  Firing effected in the forming of joints between ceramic fibres, necessary to get high green strength and at the same time open porosity. Permeability, bending and shear strength were examined to evaluate usefulness of preforms for reinforcing of composite materials by squeeze casting method. It was found out that permeability characterising  passing efficiency of gases is sufficient for the passing of liquid metal front  and thus infiltration of porous ceramic material. Bending and shear strength sharply decreased with the increasing porosity as a result of lower amount and quantity of joints between fibres. Microscopic observations revealed that they formed rounded bridges, relatively strong though small. They did not create sail or membrane that can disturb metal flow during infiltration. Preliminary attempts to squeeze cast perform confirmed proper strength and sufficient permeability what resulted in full dense, sound casting without deformation of reinforcement.  

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