Patent ID: 7472740
Filing Date: 2009-01-06
Classification: B22D,Y10T

Abstract:
1. A method of casting a composite metal ingot, comprising at least two layers, wherein pairs of adjacent layers consisting of a first alloy and second alloy are formed by applying the second alloy in a molten state to the surface of the first alloy while the surface of the first alloy is at a temperature between the solidus and liquidus temperatures of the first alloy, said first and second alloys being supplied from a first alloy pool and a second alloy pool, respectively, each of said alloy pools having an upper surface, and the first and second alloys being kept mutually separated prior to applying said second alloy to said surface of said first alloy by a vertical divider wall having a lower end positioned such that the upper surface of the second alloy pool is maintained at a level below the lower end of the divider wall, controlling the temperature of the divider wall to thereby control the temperature of the self-supporting surface of the first alloy at the position where the upper surface of the second alloy contacts the self-supporting surface, and wherein the upper surface of the second alloy pool is maintained no less than 2 mm below the lower end of the divider wall and no greater than 20 mm below the lower end of the divider wall.