A method and apparatus for casting metals in a DC mold to form an ingot or product having at least two layers formed by sequential solidification. The apparatus has at least one cooled divider wall at the entry end portion of the mold to divide the entry end portion into at least two feed chambers. Metal...http://www.google.com.au/patents/US7748434?utm_source=gb-gplus-sharePatent US7748434 - Sequential casting of metals having high co-efficients of contraction
