REMOVAL METHOD OF COATINGS FROM TITANIUM NITRIDE FROM SURFACE OF PARTS FROM TITANIUM ALLOYS Russian patent published in 2012 - IPC C23F1/26 C23F1/44 C23F17/00 

FIELD: metallurgy.

SUBSTANCE: method involves preliminary measurement of microhardness of the coating and further treatment in the solution containing the following, wt %: nitric acid 38.5 - 40.5, hydrofluoric acid 59.2 - 61.4, phenylamine 0.1 - 0.3. At that, treatment in the above solution is performed till loosening of the coating without its compete removal; after that, treated coating is removed by mechanical polishing; loosening of the coating from titanium nitride is characterised with its microhardness value H, based on the following relationship: H/H₀ = k, where k = 0.45 - 0.55 - empirical coefficient, H₀ - initial microhardness of the coating prior to dipping into etching solution, kgf/mm².

EFFECT: improvement of quality of the surface when removing the coating from titanium nitride from surfaces of products from titanium alloys.

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