| 摘要 |
Carbonaceous, composite tooling fabricated from pitch-based or coal-based cellular or porous products, "carbonaceous foams" having a density of preferably between about 0.1 g/cm<3 >and about 0.8 g/cm<3 >that are produced by: 1) conventional pitch foaming processes or; 2) the controlled beating of coal particulate preferably up to ¼ inch in diameter in a "mold" and under a non-oxidizing atmosphere. According to a specifically preferred embodiment, the starting material coal has a free swell index as determined by ASTM test D720 of between about 3.5 and about 5.0.
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