Magnetic properties of iron-based soft magnetic composites prepared via phytic acid surface treatment

Abstract

In this study, phytic acid (PA) surface treatment was used to prepare iron-based soft magnetic composites (SMCs). The composition and microstructure of the SMCs were analyzed to assess changes in the magnetic properties. As the treatment time increased, the insulating layer on the powder surface gradually thickened, changing the internal morphology and conductive path of the annular samples after compacting. The changes in the magnetic properties and core loss were attributed to the increased resistivity and enhancement of the magnetic dilution effect. The optimal soft magnetic performance (μm = 389, Pt = 235.1 mW/g measured at 100 kHz and 50 mT) was obtained by adjusting the processing time. This reduces the loss by 52.96% compared to the untreated sample and improves the application potential of soft magnetic composites at medium and high frequencies.