Trw Limited

James D Jackson

William S Blazek

Thomas S Piwonka

Philip N Atanmo

A segmented mold assembly is utilized to cast a turbine engine component having a relatively heavy hub from which relatively light vanes project. The mold assembly includes a plurality of sections which are formed of a ceramic mold material and are interconnected at flange joints. The mold sections are advantageously formed by repetitively dipping patterns in a slurry of liquid ceramic mold material to form wet coatings on the patterns. These wet coatings are dried and separated from the patterns to form the mold sections. The mold sections which are used to cast the vanes retard the removal of heat from the vanes to provide time for the hub to solidify. This can be accomplished by using relatively thick walled mold sections to form the mold cavities in which vanes are cast and relatively thin walled mold sections to form the cavity in which the hub is cast. This could also be accomplished by forming the vane mold section of material having a relatively low rate of heat removal and the hub mold section of a material having a relatively high rate of heat removal.

Mold assembly and method of making the same

A segmented mold assembly is utilized to cast a turbine engine component having an annular inner wall and an annular outer wall which are interconnected by a plurality of struts or vanes. The mold assembly includes a plurality of sections which are formed of a ceramic mold material and are interconnected at flange joints. A pair of mold sections are advantageously formed simultaneously by repetitively dipping a single pattern in a slurry of liquid ceramic mold material to form a wet coating on the pattern. This wet coating of ceramic mold material is then dried. After a covering of the desired thickness has been built up by repetitively dipping and drying the coatings on the wax pattern, the wax pattern is destroyed. To facilitate separating the mold sections after destroying the wax pattern, at least some of the wet coatings are wiped away in an area between portions of the wet coatings which will eventually form the mold sections.

Growing community of inventors

Cleveland Heights, OH, United States of America

James D Jackson