A hybrid ceramic/sand casting method of manufacturing a metal part. The method is especially suitable for manufacturing engine cylinder blocks or cylinder head, which have very small internal passages or other very small internal features. These parts are formed using a hybrid core having at least one ceramic section and at least one sand section, with the ceramic section being used to create the internal feature. A mold cavity is created for the part, and the hybrid core is positioned in the mold. Molten metal is introduced into the mold, and after the metal cools, the core is removed, thereby forming the part with the internal feature.
Barry E. Westmoreland; Douglas A. McKee; Marc C. Megel; Mark A. Tussing; Thomas E. Reinhart; David P. Branyon