Continuous metal casting method, apparatus and product

The method of producing a metal product of long length which comprises the steps of forming an elongated upwardly-traveling alternating electromagnetic field within the interior of a surrounding casting vessel, introducing liquid metal into the lower portion of the casting vessel and the field, establishing an alternating electromagnetic field acting on the liquid metal column to provide a levitation ratio between 75% and 200% of the weight per unit length of liquid metal and wherein the optimum fundamental frequency of the alternating electromagnetic field is given by the expression F=(36.rho./D.sup.2) where F is the frequency in kilohertz, .rho. is the resistivity of the liquid metal column in micro-ohm-centimeters, and D is the average diameter of the solidified metal product in millimeters to thereby reduce the hydrostatic head of the column and to maintain a predetermined dimensional relationship between the outer surface of the liquid metal column and the interior surrounding surfaces of said casting vessel, maintaining the electromagnetic field at the set value of levitation ratio so that the cross-sectional dimension of the liquid metal in the solidification zone is sufficiently large to preclude formation of a substantial gap between the outer surface of the column and the interior surrounding surfaces of the casting vessel thereby effecting optimized heat transfer conditions between the liquid metal column and the casting vessel for a given rate of production while simultaneously reducing frictional, adhesive and gravitational forces acting on the column to a minimum, moving the liquid metal column upwardly through the casting vessel, solidifying the metal while moving upwardly through said vessel and said field, and removing solidified metal product from the upper portion of said vessel.