Abstract：The classification and formation of white spot during vacuum arc remelt (VAR) was study in this paper. White spot defects were classified discrete white spots, dendritic white spots and solidification white spots. Previous work has shown that the white spot defect formation was relate to fluid flow and solidification in the molten pool atop the ingot. And the constricted arc and longer arc length was the primary reason. Therefore, the stable diffuse arc could prevent the formation of white spot defects.
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2022, Vol. 29 