electroslag remelting

metallurgy

Also known as: ESR

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Last updated

June 26, 2026

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Electroslag remelting (ESR) is a secondary refining process in metallurgy used to produce special steel products. In ESR, a consumable electrode slowly melts within a water-cooled mold. The melting is driven by a thick, superheated slag layer that is heated by a high electrical current passing from the electrode to the mold. This slag also removes sulfur from the molten steel as it drips through. The resulting ingot has a very clean surface because of the slag layer between the ingot and the mold, eliminating the need for surface conditioning. Some ESR installations can produce ingots weighing over 200 tons.1

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Electroslag remelting (ESR)
In this process, there is a slowly melting consumable electrode and a water-cooled mold for solidification, as in vacuum arc remelting, but the melting is conducted under normal atmosphere and is accomplished by a thick, superheated layer of slag on top of…
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In this process, there is a slowly melting consumable electrode and a water-cooled mold for solidification, as in vacuum arc remelting, but the melting is conducted under normal atmosphere and is accomplished by a thick, superheated layer of slag on top of…
Read More