Structural and magnetic investigations on Ni₂MnAl

Abstract
Ferromagnetic alloys undergoing thermoelastic martensitic transformations have recently become very attractive owing to the possibility of inducing giant deformations by rotating martensitic domains with an externally applied magnetic field. It is expected that ferromagnetic alloys with the Heusler stucture may exhibit a strong magnetoelastic coupling resulting in potentially interesting magneto-mechanical properties. In this paper we present preliminary results on structural and magnetic studies on Ni₂MnAl. It is shown that in this material the magnetic properties strongly depend on the heat treatment, chiefly because of the difficulty in achieving a complete L2₁ order.