低频磁脉冲处理Fe_(78)Si_9B_(13)非晶合金的低温纳米晶化

LOW TEMPERATURE NANOCRYSTALLIZATION OF Fe_(78)Si_9B_(13) AMORPHOUS ALLOY TREATED BY LOW-FREQUENCY MAGNETIC PULSING

对Fe_(78)Si_98_(13)非晶进行了低频磁脉冲处理(场强0．01—0．04 T,频率20—40 Hz,作用时间60—300 s),以红外非接触测温仪测量处理过程的试样温升,用M(?)ssbauer谱、透射电镜观察试样的微结构变化．研究表明,在磁脉冲作用下,非晶合金发生了低温纳米晶化(温升△T=7℃),晶化相α-Fe(Si)的晶粒尺寸约10 nm．析出量2．18%—9．43%;所形成的双相纳米合金对应的平均超精细磁场较非晶的原始制备态明显增加．

Amorphous Fe78Si9B13 alloys have been treated by low frequency magnetic pulsing. The temperature rise in the course of the application of pulsed magnetic field was measured by a non- contact infrared thermometer. The microstructure change of amorphous specimens after treatment was observed by MSssbauer spectroscopy and TEM. The results showed that nanocrystallization of amorphous specimens can occur at low temperature （the temperature rise ΔT=7℃. The volume content and grain size of nanocrystalline phase α-Fe（Si） are about 2.18%-9.43% and 10 nm, respectively. Compared with the as-quenched sample, the double-phase nanocrystalline alloy has obvious high mean hyperfine magnetic field.