| 摘要 |
PURPOSE:To disperse carbon fibers into a gypsum mold readily and uniformly by mixing gypsum powder with carbon fibers preseparated into a single fiber state. CONSTITUTION:Carbon fibers are cut into 5-70mm length and a sizing agent attached to the carbon fibers is removed by heating in an oxidizing atmosphere or washing away with an accent solvent to separate the carbon fibers into innumerable separated fibers. Gypsum powder is mixed with 0.01-lwt.% of the separated carbon fibers and a mixture of the gypsum powder and the carbon fibers is thrown into a circulating jet air flow to uniformly blend both the materials. The gypsum powder into which the carbon fibers are dispersed is recovered from the air flow. The amount of the gypsum powder required to produce a gypsum mold is calculated and added to a container containing prescribed amount of water. When the gypsum powder is mildly stirred by an agitating blade in a vacuum state, a gypsum slurry having the uniformly dispersed carbon fibers is obtained. The gypsum slurry is poured into a case mold, hardened, demolded and dried. |
