材料期刊网

The structure, phase transformation and magnetic properties of mechanically alloyed (MA) samples of Dy(m)Fe(92-m)Z(8) (Z = C, B) (13 less than or equal to m less than or equal to 20) have been studied systematically. The tetragonal Dy2Fe14C compound can be formed within a wide composition range, 15 less than or equal to m less than or equal to 18. When m greater than or equal to 19 or m less than or equal to 14, Dy2Fe17Cx with different Curie temperatures forms accompanying the Dy2Fe14C phase. An fee 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 Dy2Fe14B is rather narrower than that of Dy2Fe14C. When m greater than or equal to 16, Dy6Fe23 is formed. When m less than or equal to 14, a certain amount of alpha-Fe 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.