Apparatus for unidirectional infiltration of preform with molten resin or pitch

A molding apparatus for the rapid transfer of molten resin or pitch in an infiltration molding process, said apparatus comprising:

• means for melting and conveying a resin or pitch;
• a mold comprising a top portion;
• a bottom portion opposed to the top portion so that the top portion and the bottom portion form a mold cavity;
• at least one gate disposed in the top portion or the bottom portion of the mold;
• a valve for admitting resin or pitch into said gate;
• and an arrangement for venting and/or providing vacuum to the mold, said mold being arranged so that resin or pitch is conveyed from the melting and conveying means to a mold insert cavity within the mold, the mold containing protrusion means having at least one vent port for effecting a pressure gradient and flow of the resin or pitch from one side of the mold insert cavity toward an opposite side of the mold insert cavity and containing locating means for positioning a porous body within the mold insert cavity in a position that brings about unidirectional flow of the molten resin or pitch through the porous body;
• and
• means disposed at the mold to constrain the mold during injection of the resin or pitch into the mold.