High strength and high electrical conductivity of UFG Al-2%Fe alloy achieved by high-pressure torsion and aging

In this study, Al-2%Fe samples extracted from a cast ingot in the shape of rings were processed by High-Pressure Torsion (HPT) at room temperature. Suitable specimens were extracted for evaluation of mechanical properties and electrical resistivity. High tensile strength of ∼600 MPa was attained by HPT due to grain refinement down to an average grain size of ∼130 nm and by subsequent aging accompanied by nano-sized (∼10 nm) AhFe precipitates. The resulting conductivity (IACS%) was recovered from ∼40% in the steady state after HPT to well above 50% in the peak-aged condition, which is in the range of current Al electrical alloys.