METHOD OF REMOVAL OF COATS FROM PARTS MADE FROM HEAT-RESISTANT ALLOYS Russian patent published in 2003 - IPC

FIELD: chemical and thermal treatment of metals and alloys. SUBSTANCE: proposed method includes preliminary cleaning of parts from carbon deposit, pickling them in solution and removing products of interaction of solution with components of coat with the aid of solution of the following composition, mass-%: nitric acid, 25-40; fluorohydric acid, 0.5-4; iron powder, 0.2-1; chromium oxide, 0.3-1.5; water, up to 100%; parts are kept in this solution for at least 2 min at temperature of not below 18 C. Proposed method makes it possible to retain zone of diffusion interaction of components of coat applied on part with structure of parent metal (diffusion zone) at complete removal of coat. EFFECT: enhanced efficiency. 1 ex