Abstract: A method is provided for removing a fugitive pattern, such as wax or other meltable pattern material, residing inside of a refractory mold by discharging condensable vapor such as steam inside the mold to contact and melt the pattern while an exterior of the mold is subjected to a non-condensing gas atmosphere such as air outside of the mold wherein the condensable vapor inside the mold and the atmosphere outside of the mold are at substantially the same pressure. Condensable vapor is condensed inside the mold where the vapor has contacted the pattern while the exterior of the mold remains free of condenate. The condensed vapor and melted pattern material are drained out of the mold. The condensed vapor can be discharged initially inside a hollow sprue of a fugitive pattern assembly to melt the sprue and then inside the mold to melt the patterns of the pattern assembly.

Abstract: A thermally efficient method for the heating a gas permeable wall of a bonded refractory mold wherein the mold wall defines a mold cavity in which molten metal or alloy is cast. The mold wall is heated by the transfer of heat from hot gas flowing inside of the mold cavity to the mold wall. Hot gas is flowed from a hot gas source outside the mold through the mold cavity and gas permeable mold wall to a lower pressure region exterior of the mold to control temperature of an interior surface of the mold wall.

Abstract: Tooling for handling molten or hot solid aluminum and its alloys wherein the tooling is made of a passivated titanium aluminide (TiAl) intermetallic compound having a thin passivating surface oxide film formed in-situ thereon by contact with an oxygen-bearing atmosphere at elevated temperature. The surface oxide film passivates and renders the tooling non-wetted by and non-reactive with molten aluminum and its alloys and non-bonded to hot solid aluminum and its alloys.