Nano-structured Al-based alloys with additions of Ni have been prepared by electron beam evaporation. The composition dependence of the resulting microstructures and mechanical properties has been studied. The Al-Ni deposits consist of Al and A13Ni with a grain size below 100nm. Vickers hardness increases with the Ni-content and reaches values as high as 320Hv at a Ni content of around 20at.%. At higher Ni contents Vickers hardness remains almost constant at this high level. Upon annealing the Al and Al₃Ni grain grow and Vickers hardness decreases. The change of Vickers hardness follows the Hall-Petch relationship. The dispersion strengthening by the intermetallic phase of AI-Ni deposits would be estimated from the Orowan-mechanism. It is therefore concluded that the effects of both grain size refinement and dispersion strengthening contribute to the achievement of high Vickers hardness. The continuous electron beam evaporation technique is an effective method to produce nano crystalline high strength bulk material.