Abstract
Heusler alloy
Mn
2
NiGa
has been developed by synthesizing a series of ferromagnetic shape memory alloys
Mn
25
+
x
Ni
50
−
x
Ga
25
(
x
=
0
-
25
)
.
Mn
2
NiGa
exhibits a martensitic transformation around room temperature with a large thermal hysteresis up to 50 K and a lattice distortion as large as 21.3% and has a quite high Curie temperature of 588 K. The martensite shows a high-saturated field up to 2 T. The excellent two-way shape memory behavior with a strain of 1.7% was observed in the single crystal
Mn
2
NiGa
. The magnetic-field-controlled effect created a total strain up to 4.0% and changed the sign of the shape deformation effectively.