Method of producing a coating on a core

Abstract

A method of providing a member having a metal core with a nonferrous coating wherein the metal core affords strength and rigidity while the nonferrous outer coating, or cladding, provides a non-corrodible surface and wherein the cladding is of such uniform thickness that final forming of the member may be performed without penetrating or breaking the coating, or exposing the core. The cladding is applied by extruding the nonferrous material in a cross-axis die where it reaches a plastic state and passing the metal core through the plastic non-ferrous metal in the die with the high extrusion pressure creating heat to render the nonferrous metal in a plastic state and further extruding the nonferrous metal around the metal core as it exits from the die, whereby to obtain a wrought structure of the clad coating, without reducing the cross-sectional area of the core during the extrusion operations.