Abstract: A method for producing a low reactivity tungsten impregnated ceramic mold for casting refractory metals such as titanium is described. The method involves impregnation of a standard ceramic shell mold with an aqueous solution of tungstic acid and ammonium hydroxide. The saturated mold is then dried and fired to convert the tungsten compound to metallic tungsten or tungsten oxides. The process may be repeated several times to achieve the desired tungsten concentration.

Abstract: A mold for casting molten reactive and refractory metals has a facing portion comprising finely divided particles of the oxyfluorides of the metals of Group IIIa, including the lanthanide and actinide series, of the Periodic Chart (after Mendeleeff) and a back-up portion comprising finely divided particles of shell mold back-up material. The oxyfluroide content of the facing portion is essentially inert to titanium and other reactive and refractory molten metals and hence minimizes contamination by mold degradation products of metal objects cast in the mold.

Abstract: To permit efficient utilization of expensive equipment in casting mold manufacturing systems, particularly of a molding press, pattern plates are cycled in one loop of a plurality of work stations, including the station in which molding sand is applied to the mold boxes or flasks, and the single press, and a second loop also including the single press and, preferably, also the sand application station is provided in which loose patterns are placed in flasks, so that the common work stations, and principally the molding press, is efficiently utilized.