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The Vacuum Arc Remelting (VAR) process consists of the melting of an electrode, generally formed by Vacuum Induction Melting, by a controlled DC arc in a vacuum environment. The arc is established between the negative consumable electrode (cathode) and the crucible base (anode) and quickly forms a molten pool of metal.

The gap between the melting electrode and metal pool (arc gap) is precisely maintained and a controlled melt rate is established. The metal droplets falling through the arc gap are exposed to the vacuum environment and the extreme temperatures of the arc zone. This causes removal of dissolved gases, vaporization of tramp elements, and improvement in oxide cleanliness.

Because of the water-cooled crucible, the molten pool of metal formed by the metal droplets is solidified in a directional fashion. When the melt rate and arc gap are correctly controlled, solidification prevents macrosegregation and reduces the amount of microsegregation, thereby enhancing the material properties of the solidified ingot.

Toward the end of the process, the power is gradually reduced providing a controlled hot top, maximizing the yield of useful product.