Hydrostatic pressure effects on martensitic transition, magnetic and magnetocaloric effect in Si doped Ni–Mn–Sn Heusler alloys

•The pressure effects on ΔSM were investigated in Si doped Ni–Mn–Sn alloys.•The Tm and Curie temperature of the austenitic phase changes with pressure.•The maximum ΔSM of 24.5 J kg−1 K−1 at 9.7 kbar were observed for x = 1 alloy.•The RC increases for x = 1 alloy and can be used for magnetic refrigeration.

We report the hydrostatic pressure dependence of martensitic, magnetic and magnetocaloric effect in the Ni48Mn39Sn13−xSix (x = 1 and 4) Heusler alloys. The martensitic transition temperature increased with respect to pressure at the rate of 2.37 K/kbar and 0.7 K/kbar for x = 1 and 4 alloys respectively and decreases with the application of magnetic field at the rate of 1.2 K/T and 0.8 K/T for x = 1 and 4 alloys respectively. The Curie temperature of austenite phase changes marginally under pressure. The maximum magnetic entropy change (ΔSM) of 5.13 J kg−1 K−1 at 0 kbar and 24.5 J kg−1 K−1 at 9.7 kbar were observed for x = 1 alloy. However the magnetic entropy change for x = 4 alloy seems to decrease as a function of pressure.