| 摘要 |
PURPOSE:To produce the whisker-contg. high-strength preform for metal impregnation having a high void volume and good shape retaining property by incorporating fibrous gap materials into an aq. slurry contg. whiskers and inorg. binder and subjecting the slurry to dehydration molding. CONSTITUTION:The fibrous gap materials are incorporated into the aq. slurry contg. the whiskers, such as potassium titanate and inorg. binder, such as alumina sol. Org. fibers or carbon fibers are used as these gap materials. The fibers having about 0.5 to 20mum diameter and 0.05 to 100mm length are preferable and the content thereof is set equal to or below the content of the whiskers. The pH value of this slurry is increased to 4.5 to 10.0 by adding an alkaline agent thereto. Further, a high-polymer flocculating agent is added at need thereto to fix the inorg. binder to the surfaces of the whiskers. This aq. slurry is thereafter charged into a mold and is subjected to dehydration molding, and, thereafter, the molding is dried and is further preferably calcined to crystallize the inorg. binder. As a result, the preform having 65 to 92% void volume and the excellent shape retaining property is obtd. |
