Two-way shape memory effect in Ni49Fe18Ga27Co6 ferromagnetic shape memory single crystals

The two-way shape memory effect (TWSME) induced in Ni49Fe18Ga27Co6 (at%) ferromagnetic shape memory single crystals is investigated in the present work. A short superelastic cycling in compression along the [001] direction at increasing temperatures up to 453 K, with a total of 18 cycles is enough to induce fully reversible TWSME with spontaneous strain up to 5.4% and maximum work output of 27 J·kg-1 performed upon cooling through the martensitic transformation under antagonistic tensile stress. A very good correlation between martensite reorientation tests and thermal transformation under antagonistic stress has been obtained for TWSME trained samples.