Aluminum and copper and their alloys have been widely used due to relatively high strength-to-weight ratios compared with conventional steels. Processing of these alloys is typically conducted at high temperatures over extended time periods. High-pressure torsion (HPT) is a promising processing technique for introducing significant grain refinement leading to excellent mechanical properties, such as strength and ductility, in bulk metals and alloys at ambient temperatures. In the present study, in addition to the principle of grain refinement, HPT was applied for synthesizing a hybrid metal system of an Al-Cu alloy. In practice, an Al-1050 alloy and a commercial purity Cu were processed concurrently by HPT under a compressive pressure of 6.0 GPa at a rotational speed of 1 rpm for up to 60 rotations. The evolution in microstructure and the formation of intermetallic compounds were observed by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction analysis. Hardness measurements demonstrated heterogeneous distributions of hardness from the disk centers to the edges, thereby suggesting a formation of microstructural heterogeneity. This study demonstrates the feasibility of HPT processing for introducing a wide range of unique metal systems.