Microstructure and Magnetic Properties of Cu-Ag-La-Fe Immiscible Alloys with an Amorphous Phase

Abstract

The microstructure and magnetic properties of rapidly solidified in Cu_43.2Ag_32.0La_4.8Fe₂₀ (at.%) alloy, which was designed as the combination of Cu-Ag-based Cu₅₄Ag₄₀La₆ alloy with high glass forming ability and Fe, was investigated. The composite of an amorphous phase and crystalline phases was obtained in melt-spun ribbons. The spherical Fe globules, which was surrounded by Cu-rich crystalline phases, were embedded in Cu-Ag-La based amorphous matrix. The particular structure in melt-spun ribbons can be explained by the liquid phase separation and the crystallization of the separated Fe-rich liquid globules during the cooling of the thermal melt. The melt-spun ribbon shows the typical ferromagnetic magnetic properties due to the ten nano-meter ordered bcc-Fe based globules.