Magnetic properties of the Nd2(Fe1−<i>x</i>Co<i>x</i>)14B system

Abstract

We have investigated the magnetic properties of the Nd2(Fe1−xCox)14B system to improve the thermal properties of the Nd-Fe-B magnets. Nd2(Fe1−xCox)14B exists in the tetragonal form in the entire range of 0≤x≤1. In this system, the replacement of Fe by Co significantly increases the Curie temperature. The room-temperature magnetization of Nd2(Fe1−xCox)14B has its maximum value at x=0.1. However, because of the decrease in the anisotropy energy and the saturation magnetization by further substitution of Co for Fe, a reasonable substitution range of Co is suggested to be x&amp;lt;0.2 in the sintered Nd-Fe-B magnet. In this range of Co, we have succeeded in improving the reversible temperature coefficient of the remanence for the Nd-Fe-B magnets.