REAL TIME SURFACE PROPERTIES MONITORING IN CHEMICAL TECHNOLOGIES FOR COATING STRIPPING FROM GAS TURBINE BLADES

A.M. Smyslov, A.A. Bybin, R.R. Nevyantseva, E.V. Parfenov, O.G. Smolnikova, P.V. Tarasov

The paper presents a research of structure and phase composition of PVD TiN coating on steel and titanium substrates, and of diffusion aluminide coatings on nickel superalloy substrates. The chemical stripping process features have been investigated for specially developed etching solutions. The process parameters have been analyzed, and the open curcuit electrode potential has been chosen as the most informative parameter describing the surface properties during the chemical stripping of a coating from a gas turbine blade. A structural circuit of a measurement device for the electrode potential monitoring has been proposed.

Key words: protective coating, coating stripping, chemical method, surface properties monitoring, open circuit electrode potential.