| 摘要 |
PURPOSE:To produce a large-sized pattern for a monolithic ceramic shell mold by forming a pattern body of an org. self-curable packing material contg. aggregate and depositing a smooth synthetic resin film on the surface thereby constituting an expendable pattern. CONSTITUTION:A synthetic resin of spray type is coated on the inside surface of female molds 2a, 2b for forming two-split patterns and a resin film 3 is formed in order to cast a propeller blade by the monolithic ceramic shell mold having no parting planes. The molds 2a, 2b are then mated and a mandrel 5 is set to the center of a fixed mold cavity 4. The self-curable sand kneaded with an org. binder is packed therein and is cured. The expendable pattern deposited with the smooth synthetic resin film on the surface is thus obtd. The production of the large-sized expendable pattern having high strength and thermal stability is thus made possible. The pattern forms a smooth and beautiful casting surface when applied for the monolithic ceramic shell mold. |
