Method and apparatus for controlled directional solidification of a wheel casting

Abstract

A multi-piece wheel mold defining a mold cavity having a wheel rim cavity and a wheel disc cavity includes a large mass of metal adjacent to the outboard end of the wheel rim cavity and a small mass of metal adjacent to the inboard end of the wheel rim cavity. The mold also includes tapered side segments having a portion adjacent to the inboard end of the wheel rim cavity which is formed from a metal having a first conductivity of heat transfer. The side segments further have a second portion adjacent to the outboard end of the wheel rim cavity which is formed from a second metal having a second conductivity of heat transfer which is greater than the conductivity of heat transfer of the first portion. Molten metal in the mold cavity initially begins to solidify in the outboard end of the wheel rim cavity. Solidification of the molten metal then proceeds simultaneously in an axial direction across the wheel rim cavity towards the inboard end of the wheel rim and in a radial direction across the wheel disc cavity towards the center of wheel disc.

Dependencies are inferred from the claim text.