Investigation into quasi-static and dynamic tensile mechanical properties of aluminium-scandium alloy

The mechanical properties of aluminium-scandium alloy are investigated at strain rates ranging from 0.0005 to 2600 s(-1) and a temperature of 25 degrees C using a material testing system and split-Hopkinson tensile bar. The temperature dependence of the material response is investigated at elevated temperatures of 100 to 300 degrees C under a strain rate of 0.0005 s(-1). The flow stress increases with increasing strain rate but decreases with increasing temperature. The scanning electron microscope observations reveal that the fracture surface contains a large number of dimpled structures with intermetallic precipitates, which suggests a ductile failure mode. Material constants for a combined Johnson-Cook/Cowper-Symonds constitutive model are determined to describe the dynamic behaviours of aluminium-scandium alloys.