Effect of Co Content on Structural Stability and Soft Magnetic Properties for (Fe1 – xCox)86Hf7B6Cu1 Amorphous Alloy

Abstract

Amorphous (Fe1–xCox)86Hf7B6Cu1 ribbons were prepared by using the single-roller melt-spinning technique. The microstructure, crystallization activation energy, soft magnetic properties and structural defects of the samples have been investigated by XRD, TEM, DTA, VSM and positron annihilation lifetime spectra. The results show that the as-quenched alloy ribbons are structurally amorphous. The positron annihilation technique results show that for the (Fe1–xCox)86Hf7B6Cu1 (x = 0.4) amorphous alloy, the annihilation lifetime τ1 is 149.0 ps in the monovacancy-like free volume. The annihilation lifetime τ2 is 344.5 ps in the microvoid. The values of τ1 and τ2 of (Fe1–xCox)86Hf7B6Cu1 (x = 0.4) amorphous alloy are the Minimum in all of the samples, which indicates that the volumes of the monovacancy-like free volume and the microvoid in this alloy is the smallest. Combined with DTA results, the structural stability of (Fe1–xCox)86Hf7B6Cu1 (x = 0.4) is the best. The VSM results show that (Fe1–xCox)86Hf7B6Cu1 (x = 0.4) amorphous alloys display more excellent soft magnetic property.