High-coercivity Dy - Fe - X (X = C, B) alloys made by mechanical alloying

Abstract

The structure, phase transformation and magnetic properties of mechanically alloyed (MA) samples of have been studied systematically. The tetragonal compound can be formed within a wide composition range, . When or with different Curie temperatures forms accompanying the phase. An fcc structure Dy-rich phase emerges during the annealing process and its amount increases with the increment of Dy content. The composition range for the formation of is rather narrower than that of . When is formed. When , a certain amount of that is unreacted with Dy and C is left. No Dy-rich phase if found in the Dy - Fe - B series of alloys. The highest intrinsic coercivities obtained in Dy - Fe - C and Dy - Fe - B systems are 93 kOe and 70 kOe respectively.