Improving the degradation and magnetization performance of FePC amorphous alloys by annealing treatment

Abstract

The Fe₈₀P_xC_20-x ingots and amorphous ribbons (4.5 ≤ x ≤ 6.5) are arc melted and melt spun respectively. The Rhodamine B degradation performance of as spun and annealed ribbons are investigated with various methods. In present alloys, increasing P content (c_P) can inhibit the precipitation of primary α-Fe and graphite phases, and promote the formation of eutectic α-Fe + Fe₃C + Fe₃P phases in ingots and annealed ribbons. With increasing annealing temperature (T_an), the primary α-Fe grain size of the ribbons with c_P = 4.5 at.% increases gradually and that of the ribbons with c_P = 6.5 at.% increases firstly and then decreases. The degradation performance and reusability of the ribbons show a similar T_an-dependent behavior, which can be explained by the size effect of the galvanic cells. Meanwhile, the saturation magnetisation B_s and coercivity H_c of the ribbons with c_P = 4.5 and 6.5 at.% increase with increasing T_an, showing a near-linear change of the reaction rate constant k against ln (B_s·H_c). This work not only studies the mechanism of improving degradation performance for FePC amorphous alloys by annealing treatment, but also reveals a correlation between degradation performance and magnetization performance of FePC alloys.