Electrochemical production of Ti–Al alloys using TiCl 4–AlCl 3–1-butyl-3-methyl imidazolium chloride (BmimCl) electrolytes

Abstract

Electrochemical production of Ti–Al alloys was investigated using TiCl 4–AlCl 3–1-butyl-3-methyl imidazolium chloride (BmimCl) electrolytes (molar ratio 0.019:2:1). The experiments were conducted at different temperatures between 70 and 125 ± 3 °C and at various cell voltages between 1.5 and 3.0 V. Morphology and composition of deposited Ti–Al alloys were characterized using scanning electron microscope (SEM), along with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD). The Ti–Al alloys containing about 15–27 at% Ti were produced with a current efficiency of about 25–38%. TiCl 3 passivation on electrodes hinders the deposition kinetics and hence very low cathodic current density and cathodic current efficiency was obtained. This study also focused to determine the effect of process variables such as applied voltage, electrolyte composition and temperature on cathode current density, current efficiency, composition and morphology of Ti–Al alloys. The optimized condition for producing finer particle size and high Ti content in Ti–Al alloys was obtained between the applied voltages of 1.5–2.0 V and temperature ranges from 70 to 100 °C.