摘要
An isothermal section of Nd-Fe-B system at 1000℃ and the phase equilibrium relationship in Fe-Nd and Nd-B binary systems were investigated with diffusion couple by means of metallographic observation, electron microprobe analysis and X-ray diffraction.It was shown that there are three stable ternary com- pounds,Nd_2Fe_(14)B,Nd_2Fe_7B_6 and Nd_9Fe_3B_8 in Nd-Fe-B system at 1000℃.None of these phases has solu- bility,that is,they are exactly stoichiometric phases.On the other hand,there exist rather wide two-phase regions between Nd_2Fe_7B_6 and liquid as well as between Nd_9Fe_3B_8 and liquid.It was identified that there is no NdFe_2 compound in the system under atmospheric pressure.
An isothermal section of Nd-Fe-B system at 1000℃ and the phase equilibrium relationship in Fe-Nd and Nd-B binary systems were investigated with diffusion couple by means of metallographic observation, electron microprobe analysis and X-ray diffraction.It was shown that there are three stable ternary com- pounds,Nd_2Fe_(14)B,Nd_2Fe_7B_6 and Nd_9Fe_3B_8 in Nd-Fe-B system at 1000℃.None of these phases has solu- bility,that is,they are exactly stoichiometric phases.On the other hand,there exist rather wide two-phase regions between Nd_2Fe_7B_6 and liquid as well as between Nd_9Fe_3B_8 and liquid.It was identified that there is no NdFe_2 compound in the system under atmospheric pressure.