Characterisation of rapidly solidified nanocrystalline soft magnetic ribbons based on FeSiB with P and Ga additions

Abstract

Soft magnetic materials derived from rapidly solidified Fe-Si-B alloys exhibit excellent soft magnetic properties due to the crystallisation of nanoscale α-iron grains in an amorphous matrix. It has been proposed that decreasing the critical solidification rate by choosing the multi-atomic alloying system with negative enthalpies of mixing among elements can lead to further grain refinement. In the present work, an alloy with P, Ga and Al additions to satisfy the rule for decreasing the critical solidification rate was produced. The structures of as-cast and annealed alloys were investigated in detail using FESEM, supplemented by EDS, WDS and EBSD analytical tools. Additionally, surface analysis by AES and XPS was performed to characterise the phases.