EFFECTS OF HYDROGEN-SULFIDE AND TEMPERATURE ON PASSIVATION BEHAVIOR OF TITANIUM

The effects of H2S and temperature on the passivation behaviour of titanium have been investigated in H2SO4 solution by means of electrochemical polarization methods and X-ray diffraction examinations. X-ray diffraction investigations did not reveal sulphides on titanium surfaces anodically oxidized in H2S-containing solutions. Titanium sulphides do not take part in the anodic process. The composition and structure of the passive layer are not altered by H2S. Breakdown does not occur even in chloride-containing solutions saturated with H2S. On the basis of the established relations and thermodynamic considerations, the influence of H2S and temperature on the hydrogen uptake by titanium and the role of titanium hydride in the formation of the passive film are discussed. © 1990.