Carbon foams have attracted considerable recent interest because of their multi-functionality,offering a combination of high strength, low density, low thermal expansion, and a wide,controllable range of thermal conductivities. Among the many potential applications of carbonfoam is use as core material in tooling for the high-rate production of composite materials. Intooling applications, a face sheet is applied to the foam to provide durability to the workingsurface. The coefficient of thermal expansion of the carbon foam material is low, making it anideal match for carbon fiber composites typically used as such laminates.This paper describes working solutions that enable the use of carbon foam (0.16-0.32 g/cm~3) as acore material in composite tooling. These solutions include techniques for machining carbonfoam, bonding foam blocks together to produce larger-sized tools, adhering uncured carbonfiber-based laminates to the foam surface, and drying and venting the material to removeunwanted moisture. Adhesive materials are evaluated for bonding foam blocks; those thatperformed well are suitable for use up to 200-250°C. Flexural testing of bonded foamdemonstrates that the bond is in many cases stronger than the foam itself. Adhesive sealantmaterials to be applied between the foam surface and several pre-preg composite layers are alsoevaluated. Optical micrographs demonstrate that a resin-based sealing material offers goodadhesion and sealing of the porous foam surface. Minimum sizes for venting channels to removeunwanted moisture from fully-sealed composite tools are also determined. The results presentedhere are discussed with respect to use in production rate tooling applications.
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