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Purpose -The purpose of this paper is to study the use of titanium as a protecting element for aluminum in alkaline conditions. Design/methodology/approach -Aluminum coatings containing up to 20 weight per cent Ti6Al4V were produced using laser cladding and were investigated using light optical microscope, scanning electron microscope -energy-dispersive X-ray spectroscopy and X-Ray Diffraction, together with alkaline exposure tests and potentiodynamic measurements at pH 13.5. Findings -Cladding resulted in a heterogeneous solidification microstructure containing an aluminum matrix with supersaturated titanium (Ͻ1 weight per cent), Al 3 Ti intermetallics and large partially undissolved Ti6Al4V particles. Heat treatment lowered the titanium concentration in the aluminum matrix, changed the shape of the Al 3 Ti precipitates and increased the degree of dissolution of the Ti6Al4V particles. Corrosion testing showed significant localized dissolution of the aluminum matrix. Research limitations/implications -Increased titanium concentration and heat treatment gave improved alkaline corrosion properties. At pH 13.5, the Al 3 Ti phases were protected, while the aluminum matrix corroded. Practical implications -For alkaline corrosion-protection of aluminum in the automobile industry, titanium might be useful at pH values below 13.5 or by using other coating techniques. Originality/value -This is the first study testing the use of titanium as a protective element of aluminum in stringent alkaline conditions.

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