Claims
- 1. The process of removing an aluminide coating from a nickel superalloy article characterized by contacting the coating with a stripping solution having a composition consisting essentially by volume percent of 43-48 concentrated nitric acid, 7-12 concentrated hydrochloric acid, 40-50 water, at least 0.016 mole/liter CuSO.sub.4 and 0.008-0.025 mole/liter ferric chloride.
- 2. The process of claim 1 wherein the composition is more particularly characterized as 43-48 concentrated nitric acid and 9-11 concentrated hydrochloric acid, 41-48 water, and wherein the molar ratio of FeCl.sub.3 and CuSO.sub.4 is maintained at about 1:2.
- 3. The process of claims 1 or 2 wherein the solution is maintained at about 60.degree.-71.degree. C. and wherein the article is removed from contact with the solution and vapor blasted at periodic intervals.
- 4. A stripping solution for removing an aluminide coating from a nickel base superalloy consisting essentially by volume percent of 43-48 concentrated nitric acid, 7-12 concentrated hydrochloric acid, 40-50 water, at least 0.016 mole/literCuSO.sub.4 and 0.008-0.025 mole/liter ferric chloride.
- 5. The stripping solution of claim 4 more particularly characterized as 43-48 concentrated nitric acid, 9-11 concentrated hydrochloric acid, 41-48 water, and wherein the molar ratio of FeCl.sub.3 and CuSO.sub.4 is maintained at about 1:2.
Government Interests
The Government has rights in this invention pursuant to Contract F33657-79-C-0002 awarded by the Department of the Air Force.
US Referenced Citations (7)