Effect of magnetic field annealing on the magneto-elastic properties of nanocrystalline NiFe2O4

The effect of magnetic-field annealing on the strain sensitivity (q) and saturation magnetostriction (λs) of NiFe2O4 nanoparticles synthesized by citrate-gel method was investigated. The use of field-annealing resulted in improved magnetoelastic properties at the expense of coercivity. A maximum λs of −40 ppm at 2 kOe, associated with q value of −3.3 ppm/Oe at 5 Oe was achieved in the field-annealed NiFe2O4.