• González, J.
• Miguel, C.
• Murillo, N.

Abstract

<jats:p>The magnetic anisotropy induced by stress annealing (500 MPa) in Fe73.5Cu1Ta3Si13.5B9 amorphous alloy has been investigated. Such thermal treatment was carried out by means of the Joule heating technique (current density ranging from 20 to 40 A/mm2). As a result, a uniaxial in-plane magnetic anisotropy was induced in the samples. The dependence of this induced anisotropy on the current density shows a maximum (1000 J/m3) around 34 A/mm2, which can be connected to the first stages of the crystallization process, followed by a minimum at 37 A/mm2. The coercive field increases with this kind of thermal treatment, and is around 10–15 A/m for the optimum nanocrystalline state, which is one order of magnitude larger than that reported for this nanocrystalline material treated in conventional furnace. The variations of the coercive field after stress annealing seem to be correlated to the induced magnetic anisotropy behavior. The minimum anisotropy occurs for the optimum nanocrystallization process. The induced anisotropy should be mainly understood as of magneto-elastic character arising in the FeSi grains due to internal stresses.</jats:p>

Topics

• density
• impedance spectroscopy
• amorphous
• grain
• annealing
• current density
• crystallization
• coercivity