Effects of Si and/or Ti Addition on the Microstructure and Magnetic Properties of Fe–Cr–Co Ribbons

Fe-Cr-Co hard magnetic ribbons with low Co content were prepared by melt-spinning coupled with multistep aging process, in which a certain amount of Si and Ti were added separately or together. This paper focuses on three types of ribbons, which are 61Fe-26Cr-12Co-1Si, 62Fe-25Cr-12Co-1Ti, and 62Fe-24Cr-12Co-1Si-1Ti ribbons, to investigate systematically the effects of single or combined addition of Si and Ti on phase structure, microstructure, magnetic structure, and magnetic properties of Fe-Cr-Co based ribbons at different states. It has been found that single Si addition is effective to improve the coercivity, whose value can reach up to 1026.6 Oe in 61Fe-26Cr-12Co-1Si ribbons, even higher than that of traditional bulk Fe-Cr-Co alloys. Single Ti addition facilitates the orientation growth along <; 100 > directions of body centered cubic-type phases in as-spun ribbons, resulting in higher remanence. Furthermore, combined addition of the Si and Ti can enhance the orientation degree of not only the as-spun ribbons but also the aged ones. Consequently, the highest remanence of 10106.7 Gs can be achieved in 62Fe-24Cr-12Co-1Si-1Ti ribbons treated by seven-step aging.