Precipitate formation and grain refinement of Mg-Al-Sn alloy during hot deformation

Abstract

Magnesium alloys are very popular in the automobile industry due to its high strength to weight ratio. However, the use of commercial magnesium alloys as sheet is limited by room temperature ductility. One way to improve the ductility may be to form precipitates during hot rolling. These may delay dynamic recrystallization, possibly leading to grain refinement, which is known to improve ductility. Equilibrium diagrams obtained from thermodynamic modeling software FactSage were used to design Mg-3Al-2Sn alloy, which should form Mg2Sn precipitates during hot rolling temperatures around 300°C. To investigate this prediction, the alloy was cast in a copper mould and precipitates formation characteristics were studied by using optical microscope (OM), scanning electron microscope (SEM) equipped with an energy-dispersive X-ray spectroscopy (EDS).