Fe44Co20Nd7Nb4B25大块非晶合金磁性及热稳定性研究

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l164kA/m;退火温度为963 K时,剩余磁感应强度研和最大磁能积(BH)max的值最大,分别为0.27 T和15.79 kJ/m3.

Magnetic Properties and Thermal Stability of Fe44Co20Nd7Nb4B25 Bulk Amorphous Alloy

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