宽过冷液相区铁基非晶合金的形成和磁性

用熔体急冷法制备出具有明显的玻璃转变和较宽的过冷液相区的Fe-Co-(Nb)-Zr-B非晶合金，研究了热稳定性和软磁性能。结果表明，在Fe-Co-Zr-B四元合金中添加适量的Nb可以显著扩大过冷液相区，提高合金的热稳定性。当冷却速率降低时，急冷合金具有非晶和纳米晶的复相结构。非晶合金的饱和磁化强度随Nb含量的增加而减小。不同Nb含量的非晶合金的饱和磁致伸缩系数均较低。在低于晶化温度的温度下退火可以有效地降低矫顽力，改善软磁性能。晶化导致软磁性能降低。

FORMATION AND MAGNETIC PROPERTIES OF FERROMAGNETIC AMORPHOUS ALLOYS WITH WIDE SUPERCOOLED LIQUID REGION

Fe-Co-(Nb)-Zr-B amorphous alloys with an obvious glass transition and a wide supercooled liquid region before crystallization were successfully formed by means of melt-spinning. The thermal stability of the supercooled liquid and magnetic properties were also investigated. The enhancement of the thermal stability and glass-forming ability was found in the replacement of Zr by 2%~4% (atomic fraction) Nb. The structure of the melt-spun alloys changes to amorphous and nanocrystalline phases at a relatively low cooling rate. The saturation magnetization of the alloys decreases with increasing Nb content. The saturated magnetostriction of the glassy alloys with different Nb content is comparatively low. The coercive force is lowered and the soft magnetism is improved by annealing treatment at the temperature below the crystallization temperature. The crystallization leads to a significant decrease in the soft magnetic properties.