Fe44Co20Nd7Nb4B25大块非晶合金磁性及热稳定性研究

Magnetic Properties and Thermal Stability of Fe44Co20Nd7Nb4B25 Bulk Amorphous Alloy

摘要:

采用铜模吸铸法制备了Fe44Co20Nd7Nb4B25大块非晶合金，利用差示扫描量热仪 (DSC)、X射线衍射仪 (XRD)、高分辨透射电镜 (HRTEM) 和振动样品磁强计 (VSM) 研究了该合金的结构、非晶形成能力、热稳定性及磁性能。结果表明：该合金为完全非晶结构，在室温下表现为良好的软磁性，并具有较好的非晶形成能力和热稳定性，晶化激活能Ep为642 kJ/mol。退火后该合金表现为硬磁性，退火温度为1003 K时，内禀矫顽力iHc达到最大值，为1164 kA/m；退火温度为963 K时，剩余磁感应强度Br和最大磁能积(BH)max的值最大，分别为0.27 T和15.79 kJ/m3

Abstract:

Fe44Co20Nd7Nb4B25 bulk amorphous alloy was prepared by copper mold casting. The microstructure, glass-forming ability, thermal stability and magnetic properties were investigated by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM). It is found that Fe44Co20Nd7Nb4B25 alloy with amorphous structure exhibits good soft magnetic property, excellent glass-forming ability and thermal stability. The value of activation energy, Ep, is 642 kJ/mol. The annealed sample shows hard magnetic behavior, and the maximum value of intrinsic coercivity (iHc) is 1164 kA/m after annealing at 1003 K. When annealed at 963 K, the values of remanence (Br) and maximum energy product ((BH)max) reaches a maximum of 0.27 T and 15.79 kJ/m3, respectively