Surface modification of titanium is of interest considering the necessary improvement of mechanical properties of this material for applications as, for example, medical implants. This work is devoted to the formation of a layer with a high content of the titanium aluminides Ti3Al and TiAl below the surface by high dose aluminium implantation. If the maximum aluminium concentration exceeds 20 at.% precipitation of Ti3Al is detected by X-ray diffraction already in the as-implanted state. For maximum aluminium concentrations between 50 and 55 at.% the phase TiAl is found beside Ti3Al after annealing at 70 degreesC. For a double implantation resulting in an aluminium concentration of approximately 60 at.% in the depth range between 100 and 200 nm a disordered fee TiAl phase is observed after implantation as precursor for the ordered tetragonal TiAl formed by subsequent annealing at 60 degreesC. The influence of a pre-implantation of 3 x 10(17) V cm(-2) on the phase formation is also reported. The depth dependent maximum hardness in the near surface range increases with increasing Al dose up to a factor 4. Significantly enhanced wear resistance is observed for Al doses greater than or equal to 10(18) cm(-2) after annealing. High dose implantation of Al into Ti results in an enhanced corrosion in 5 M HCl. However, subsequent annealing reduces the corrosion current compared to unimplanted Ti.