Influence of temperature on the reduction mechanism of Ti(III) ions on iron in the LiF–NaF–KF eutectic melt and on the electrochemical behavior of the resultant titanium coatings

The electroreduction mechanism of Ti(III) ions on iron in the LiF–NaF–KF eutectic melt was studied at 700 and 900 °C using cyclic voltammetry. At both temperatures, the reduction occurs through a three-electron transfer, but at 700 °C only pure titanium is deposited, whereas the successive formation of Fe2Ti and FeTi intermetallic compounds precedes pure titanium deposition at 900 °C. At 900 °C under open-circuit conditions, the different phases appear successively at the electrode/electrolyte interface by interphase movements due to intermetallic diffusion. At the same temperature but under anodic polarization, each phase appears at the electrode surface according to a layer-by-layer dissolution.