(Ti,Al)N films with increasing nitrogen content were grown by reactive cosputtering and characterized by auger electron spectroscopy, grazing x-ray diffraction, polarization curves, electrochemical impedance spectroscopy, nanoindentation, and atomic force microscopy. For Ti/Al ≈ 1 the Ti1−x AlxN phase is always present, but lower nitrogen contents lead to an additional phase, probably α–Ti(Al), which causes a decrease in hardness and Young's modulus. The increase of nitrogen content results ina decrease of surface roughness or a more compacted surface coating, according to the impedance results.