Galvanic Deposition of Ti atop Al 6061 Alloy

For the first time, galvanic deposition of Ti is reported from aqueous solutions containing 17 mM HF and 10 mM K2TiF6 at pH 2.73 onto Al 6061 alloy. X-ray diffraction yields peaks consistent with a polycrystalline Ti deposit, and electrical resistivity measurements are also consistent with metallic Ti, not TiO2. Elemental analysis by energy dispersive X-ray (EDX) spectroscopy demonstrates the as-deposited film contains ∼90 atom% Ti. The galvanic Ti deposit improves the corrosion resistance of the underlying Al substrate, as illustrated by voltammetry and electrochemical impedance spectroscopy studies in several electrolytes. Deposition for 30 h. yields a 14 μm thick, silver-gray Ti film.