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

Abstract

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 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.