Method for controlling carbon content of electroslag remelting 1 ton of nickel-based superalloy cast ingot

A method for controlling the carbon content of an electroslag remelting nickel-based superalloy cast ingot comprises the following steps: a remelting step: melting a remelting electrode in a slag bath under the action of resistance heat of liquid slag to form liquid metal, and enabling the liquid metal to flow into a metal molten pool; a solidification step: enabling the liquid metal to flow into a crystallizer from the metal molten pool for cooling to sequentially form the tail and the head of the cast ingot; wherein in the remelting step, the remelting step comprises a sub-step of melting a remelting electrode and a sub-step of supplementing carbon to a slag bath by using a carbon supplementing element, and the carbon supplementing element is used for supplementing the carbon content deviation between the tail part and the head part of the cast ingot. The problem of carbon content deviation of the head and the tail of the cast ingot is solved by a method of supplementing carbon into the slag bath, and adver