METHOD FOR FIRING CERAMIC AND REFRACTORY METAL CASTING CORE

PROBLEM TO BE SOLVED: To provide a method for forming a composite core of a ceramic casting core element and a non-ceramic casting core element. SOLUTION: An exemplary process 20 for forming a composite casting core comprises: a step 22 where one or more refractory metal cores are formed; a step 24 where a ceramic material is over-molded so as to cover a part of the refractory metal core(s); a step 28 where a heating occurs in an oxidative atmosphere in a heating chamber such as a kiln; a step 40 where the chamber air is purged with a non-oxidative gas; a step 42 where the composite core is further subjected to non-oxidative firing; and a step 50 where cooling is performed. By the investment casting using the composite core, the casting for fine features whose manufacture is difficult can be improved. COPYRIGHT: (C)2008,JPO&INPIT