Nanocrystalline Fe87Zr7Al2B3Cu1 ribbons

A new nanocrystalline alloy with the nominal composition Fe87Zr7Al2B3Cu1 was obtained directly from the melt-spinning process, in the ribbon shape. There is a positive influence of the as-quenched nanograins on the soft magnetic characteristics induced by the heat treatment of the as-cast material. The 2% Al addition determines the decrease toward zero of the saturation magnetostriction in the fully nanocrystallized samples and, as a consequence, the magnetoelastic anisotropy decreases giving rise to excellent soft magnetic characteristics (μe = 69.6 × 103 after optimum annealing of the as-quenched material). The magnetic and mechanical properties of the Fe87Zr7Al2B3Cu1 ribbons are significantly improved by a two stages heat treatment: isothermal pre-annealing before the onset of the primary crystallization, for structural relaxation, followed by dc Joule heating, for the development of a more homogenous structure.