PRODUCTION OF UNIDIRECTIONALLY SOLIDIFIED STEEL INGOT

摘要

PURPOSE:To eliminate porosity and inverse V segregation and to prevent formation of coarse dendrite by cooling forcibly and quickly the surface of the solidified layer of the molten metal charged into a casting mold from which heat is extracted only in one direction at the point of the time when the solidified layer is formed in a prescribed region. CONSTITUTION:A molten metal 6 is charged into an upwardly expanded casting mold 1 of which the wall on the inside surface side is insulated from heat by a heat insulating sleeve 3. The solidified layer of the metal 6 from which the heat is extracted by a molding board 4 is separated from the board 4 when said layer is formed to the region up to at least 100mm. from the board 4 side. Water is directly sprayed onto the surface of solidified layer of the molten metal to cool forcibly said layer.