Mechanical Behavior of an Al–Mg–Mn–Sc Alloy with an Ultrafine Grain Structure at Cryogenic Temperatures

Abstract

The mechanical properties of an Al–Mg–Mn–Sc alloy with a grain size of ≈0.7 μm were examined at temperatures ranging from 77 to 293 K. An ultrafine grain structure was produced by equal‐channel angular pressing at 593 K up to a total strain of ≈12. It was demonstrated that extensive grain refinement enhances strength and ductility at ambient and cryogenic temperatures and highly enhances fracture toughness at room temperature. The alloy exhibits a well‐defined ductile–brittle transition attributed to the influence of temperature on nucleation and the growth of microvoids.