Phase Diagram of the Nd-Fe-B Ternary System

Abstract

An experimental study of the liquidus projection in a phase diagram of the Nd-Fe-B ternary system has been carried out. In the Nd-poor region, it is found that two phases, Fe 2 B and Nd 2 Fe 7 B 6 (T 2 ), coexist with the liquid. Two monovariant curves, L\rightleftharpoonsFe+Fe 2 B and L\rightleftharpoonsFe 2 B+T 2 , join and form the transition reaction, L+Fe 2 B\rightleftharpoonsT 2 +Fe. The end point of the liquid in the Nd-poor regions is the ternary eutectic point, L\rightleftharpoonsFe+Nd 2 Fe 14 B(T 1 )+T 2 . The T 2 and Nd 2 FeB 3 (T 3 ) phases simultaneously solidify from the liquid. In the Nd rich region. T 1 phase, T 2 phase and (Nd) solid solution solidify from the liquid at the end point of the liquid.