| Metallic glass has attracted wide interest due to its special physical, chemical and mechanical properties. The structural relaxation occurs when amorphous alloys were annealed below Tg, affecting the physical, properties, magnetic and structure of amorphous alloy. High magnetic fields are capable of delivering non-contact high-intensity energy delivered to the material on the atomic scale, thereby changing the arrangement matching and migration behavior of atoms, impacting microstructure and properties of the material. In this study, the thermal field and magnetic field were combined to investigate the Ni40Cu5Ti16.5Zr2s.5Al10 amorphous alloy isothermally annealed under a strong magnetic field. The thermodynamics and various of physical properties such as density, hardness, magnetic properties in the relation of Ni40Cu5Ti16.5Zr28.5Al10 amorphous alloy were investigated by X-ray diffraction analyzer (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM) and other means, in order to find the structure evolution in the conclusions were summarized as follows.1. XRD analysis of the amorphous alloys after annealing showed that the alloys remains amorphous structure without apparent crystalline phase precipitates. The nearest atomic spacing of amorphous alloys is reduced slightly, the medium degree order of amorphous alloys increases with the increasing temperature, while the medium-range clusters structure of the amorphous alloy evolves from solidified metastable medium range order structure to crystalline phase like medium range order structure.2. The crystallization kinetics of Ni40Cu5Ti16.5Zr28.5Al10 amorphous alloy in a continuous heating process show that the characteristic temperature of amorphous alloy has significant dynamic effects. With increasing temperature, the Tp, Tx of the alloy decrease. The Kissinger equation, Augis-Bennet equation were used to fit the characteristic temperatures of metallic glass. We found that two equations could well describe the relationship between the characteristic temperature of amorphous alloy and the heating rate. The activation energy of amorphous alloy is nonlinear increase.It is because of the amorphous formation of ordered clusters similar to quenched nuclear before relaxation annealing, which provides preparations for the formation of the critical nucleus can reduce the crystallization barrier, make the crystallization process in advance and reduce the peak crystallization temperature. This ordered duster structure is different from the structure of stable crystalline phases in the period of crystallizable, hence strong driving force is required in the phase transformation. Inflection point occurs at 390? have the alloy prefered to grain growth than nucleation due to the formation of the new kind of cluster.3. On the resistivity of amorphous alloys studies show that with increasing temperature, structural relaxation will cause the decline in the number of which act as electron scattering centers disordered positions, decreasing the resistivity of amorphous alloy. VSM analysis showed that the Hc of the alloy decreased and the Ms increase after relaxation coercivity. Applying magnetic field promotes the decrease of coercive force and increase of saturation magnetization, but shows little effect on the magnetic anisotropy.In addition, little density and hardness changes were found in the bulk amorphous alloy of different annealing conditions. |
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