The Finding of Elastocaloric Effect in the Lightweight Shape Memory Mg-Sc Alloy

The Mg-Sc alloy is a kind of lightweight magnesium alloy. Its density (2 g/cm3) is just one-third of the practical NiTi shape memory alloys. The elastocaloric effect is firstly realized in this lightweight Mg-Sc alloy. The temperature decrease (ΔT) caused by this effect reaches to 0.25 K at 116 K. The elastocaloric effect is attributed to the stress-induced martensite transformation. The stress-induced entropy change (ΔS σ ) of 8.22 J kg -1 K -1 is estimated. The present Mg-Sc alloy exhibits good superelastic behavior at low temperatures due to the β phase with bcc structure in the matrix. Much better elastocaloric and superelastic performance would be expected by increasing the content of β phase in the Mg-Sc alloy. The finding of the elastocaloric effect in the lightweight Mg-Sc alloy provides the potential for the application of the lightweight magnesium alloy in the solid state cooling field.