Microcellular graphitic carbon foams for next generation structures and thermal management

Microcellular, open cell foams can be produced from anisotropic pitch with graphitic planes aligned along the struts. The process sequence includes blowing, stabilizing, carbonizing, then graphitizing the foam, similar to the process for manufacturing pitch-based carbon fibers. A foam can be blown into a mold for net-shape composites or processed into an anisotropic reinforcement. Model graphitic foams have been analytically predicted to have a compression modulus of approximately 2 GPa with a density of about 0.1 g/cm³. The measured properties of the carbonized and graphitized foams are dependent on the foamed density and are tailorable to specific applications. Specific thermal conductivities as high as 129 (copper = 45) [W/m-K]/[g/cm³] have been measured. The mechanical properties of these foams can be made comparable to existing core materials and thermal properties can be made to be acceptable for heat exchange applications.