METHOD OF REMOVAL OF CORUNDUM AND QUARTZ- CONTAINING CERAMIC CORES FROM INTERNAL HOLLOWS OF CASTINGS Russian patent published in 2000 - IPC

FIELD: foundry, particularly, investment casting with oriented crystallization of complicated profile parts, for instance, blades. SUBSTANCE: preliminarily softened cores from castings are removed in boiling alkali solution with concentration of 565-600 g/cu.dm. Added to solution is ethanoic acid with its concentration in leached solution of 10.2-15.29 g/cu.dm. Treatment is carried out for, at least, 20 h. Addition of ethanoic acid intensifies leaching process and needs no complicated equipment. EFFECT: higher quality of castings due to absence of corrosion of casting surfaces. 1 tbl