Vacuum arc remelting apparatus and process

摘要

A VAR process is conducted in an apparatus (10) characterized by a crucible wall that provides a stable shelf anchor. The VAR apparatus includes a furnace chamber (14), a consumable electrode (12) formed of a material to be remelted within the furnace chamber and a crucible (16) within the furnace chamber. The crucible (16) has a wall that forms a vessel to collect melt material from the consumable electrode (12). At least part of the wall is textured to provide area for mechanical stabilization of the shelf (42) as the underside of the shelf melts and the upper side of the shelf forms. In a vacuum arc remelting process, a consumable electrode (12) is loaded into a furnace chamber above a cooled crucible having a textured wall that forms a vessel to collect melt material from the consumable electrode (12). The process includes striking a direct electric current between the electrode and a bottom of the crucible (16) to cause melting of material from a tip of the electrode. Melt material is collected from the tip in the crucible (16). The melt material is cooled to form an ingot characterized by a shelf of solidified material forming adjacent the textured section of the crucible (16) wall in advance of a lower boundary of solidifying material.