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

Abstract The Fe80P x C20-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.