Vacuum or air casting using induction hot topping

摘要

A method and apparatus for vacuum or air casting a molten superalloy, or other metal or alloy, containing an oxygen-reactive alloying element to form a cast part involves introducing the molten metallic material (melt) into a preheated mold having a melt reserovir, such as for example a mold pour cup, and gating for feeding the melt to one or more mold cavities. An induction coil disposed locally adjacent to the mold pour cup is energized in a manner to locally heat excess melt left in the melt reservoir to maintain it molten as the melt solidifies under vacuum or in air in the mold cavity to avoid shrinkage defects in the cast part.