Magnetic Properties and Structure of Fe-based Amorphous Alloys

研究了铁基非晶合金的高场磁化、交流磁化率、磁冷却、硬度、线性磁致伸缩、强迫体积磁致伸缩、热膨胀、弹性性能、中短程有序结构和穆斯堡尔效应。主要结果如下：1)由交流磁化率、磁致冷效应和微分磁化率决定的强迫体积磁致伸缩的温度依赖关系在自旋冻结温度出现峰值。2)在低温下，线性磁致伸缩的温度依赖关系表现出显著的热滞。这一行为与SiN玻璃态的弛豫密切相关。3)居里温度以下硬度的陡峭依赖是由较大的自发体积磁致伸缩引起的。4)非晶态合金的磁性对结构的变化非常敏感。5)由于横向成分的冻结，内部磁场的温度依赖性在自旋冻结温度以下明显增加。6)铁基合金向纯非晶铁的异质素位移外推非常接近Upsilon-Fe的值。这些合金的四重溅射约为0.4，反映了非晶态结构。

High-field magnetization, AC Susceptibility, magnetic cooling, hardness, linear magnetostriction, forced-volume magnetostriction, thermal expansion, elastic properties, short- and medium-range order structure and Mossbauer effect in Fe-based amorphous alloys have been investigated. The main results are summarized as follows;1) The temperature dependence of the forced volume magnetostriction shows the peak at the spin freezing temperature determined from AC susceptibility, magnetic cooling effect and the differential susceptibility.2) The temperature dependence of the linear magnetostriction exhibits a remarkable thermal hysteresis at low temperatures. This behavior is closely correlated with the relaxation of the sin glass state.3) The steep temperature dependence of the hardness below the Curie temperature is caused by a large spontaneous volume magnetostriction.4) The magnetic properties of the amorphous alloys are very sensitive to the structure change such as the coordination number and the atomic distance.5) The temperature dependence of the internal magnetic field shows a distinct increase below the spin freezing temperature due to the freezing the transverse component.6) The extrapolation of the isomer shift of the Fe-based alloys to pure amorphous iron is very close to the value of UPSILON-Fe. The quadruple spulliting of these alloys is about 0.4, reflecting the amorphous structure.