CORROSION BEHAVIOR IN ACID-SOLUTION OF (TI, CR)N-X FILMS DEPOSITED ON GLASS

Some (Ti, Cr)N-x films were deposited on a glass substrate by reactive cathodic sputtering. This kind of substrate was chosen to evaluate the electrochemical properties of the deposit without any galvanic coupling with a metal substrate. The Ti/Cr ratio in the coatings was varied by using different Ti/Cr area ratios in the cathode. Auger analysis and X-ray diffraction were used to characterize the chemical composition and the microstructure of the various nitride coatings produced. The X-ray diffraction characterization of the bimetallic nitrides showed the presence of an f.c.c. structure with diffraction peaks which are situated between those of the TiN and CrN phases. As the chromium amount increases, we observed the shift of these peaks towards the CrN peaks and the appearance of a structure which is increasingly microcrystalline. Chromium adjunction appeared to be interesting as far as the corrosion resistance of titanium nitride is concerned.