Magnetostrictive and structural properties of FeCoGa films

Abstract

Fe 81 − x Co x Ga 19 (with x ranging from 0 to 19 at. % Co) films were made by the dc magnetron sputtering method. We have studied the structural (phases, texturing, and grain size D), magnetic (saturation magnetostriction λS and coercivity HC), mechanical (Young’s modulus Ef and hardness Hf), and electrical (electrical resistivity ρ) properties of these films. The main results are as follows: (i) all the films are (110) textured; (ii) the bct phase (with twinned grains) coexists with the bcc phase only in the case of x≤3 at. % Co; (iii) λS increases steadily from 42 to 86 ppm, as x increases from 0 to 19 at. % Co; and (iv) ρ reaches the saturation limit, about 200 μΩ cm, when 19≥x≥15 at. % Co. In conclusion, we report that the Fe62Co19Ga19 film has the optimal magnetic, mechanical, and electrical properties among all the FeCoGa films measured.