Temperature dependence of magnetic properties of Nd-Fe-B magnets

Abstract Temperature dependence of the magnetic properties of two types of neodymium-iron-boron magnets, one with an intrinsic coercivity ( H ci ) of 13000–15000 Oe and the other with 17000–23000 Oe, were examined. Two different techniques were used for these measurements. The results indicate that H ci variation with temperature is more rapid than the anisotropy field variation suggesting that thermal activation of domain walls and thermal effects on nucleation sites play a key role. Temperature dependencies of B r on cobalt containing alloys are also reported.