Microstructure, magnetic properties, and exchange bias in (Mn0.7Co0.3)65Sn35 alloy ribbons

Abstract

Abstract Discussed in this work are the microstructure, magnetic properties, and exchange bias in (Mn0.7Co0.3)65Sn35 alloy ribbons. After annealing, the crystalline grains grow distinctly from ~0.93\u202fμm to ~8.41\u202fμm. The surface of ribbon samples becomes more regular and dense. The ribbons reveal a ferromagnetism with the Curie temperature TC\u202f~\u202f169\u202fK, which is determined from the thermomagnetic M(T) measurements. The maximum magnetic entropy change ~4.5\u202fJ\u202fkg−1\u202fK−1 is obtained around ferromagnetic-paramagnetic transition under the field change of μ0ΔH\u202f=\u202f0–7\u202fT. Large exchange bias field of μ0HEB\u202f=\u202f80\u202fmT is achieved at T\u202f=\u202f2\u202fK when the cooling field is μ0HCF\u202f=\u202f0.2\u202fT. The reasons for the appearance of ferromagnetism and large exchange bias effect are discussed.