Effect of temperature and strain rate on tensile behavior of ultrafine-grained aluminum alloys

Ultrafine-grained Al–4Y–4Ni and Al–4Y–4Ni–0.9Fe (at.%) alloys were synthesized by the consolidation of atomized powders and subsequent hot extrusion. The mechanical behavior of these two alloys has been studied by performing uniaxial tension tests ranging from room temperature to 350°C. These alloys, with high volume fraction of second-phase particles, exhibited ambient temperature tensile strength ranging from 473 to 608MPa and plastic elongation ranging from 6.7 to 9.6% at an initial strain rate of 1×10−3s−1. However, lower ductility was observed with decreasing strain rate at the intermediate temperature ranging from 150 to 250°C for Al–Y–Ni–Fe alloys due to limited work hardening.