Magnetic Properties and Magnetic Entropy Changes of Annealed and Melt-spun DyCo2 Alloy

Abstract
Structure and magnetic properties of annealed and melt-spun DyCo2 alloy were investigated using X-ray diffraction (XRD), transmission electron microscopy (TEM) and vibrating sample magneometer (VSM). They both crystallize in the MgCu2-type structure. Curie temperature (T C) of them vary slightly, while their coervicities change remarkably. Annealed DyCo2 alloy has a rather large magnetic entropy change (|ΔS M|) near T C. The magnetization of melt-spun DyCo2 alloy changes gradually in the vicinity of T C. This fact leads to a relatively small |ΔS M| in melt-spun DyCo2 alloy, but the temperature range of |ΔS M| is widen, which is more effective in utility.