纳米超微晶Fe73.5Cu1Mo3Si13.5B9合金显微结构和磁性的研究

对纳米晶Fe_73.5Cu₁Mo₃Si_13.5B₉合金的原始制备态和各退火态样品进行了室温Mossbauer谱研究,结果表明晶化态的合金存在α-Fe(Si)微晶相和晶界的非晶相。晶相和非晶相内场和面积随退火温度的变化是退火时Cu,Mo,B等成分的扩散和在各相中的再分配引起的。最佳磁性能对应非晶相中的铁量占合金铁总量的30％左右,超微晶合金的双相无规各向异性模型表明,一定量的非晶相对保持纳米晶优异的软 关键词：

THE MICROSTRUCTURE AND MAGNETIC PROPERTIES STUDIES OF NANOCRYSTALLINE Fe73.5Cu1Mo3Si13.5B9 ALLOY

The Mossbauer spectra were measured at room temperature for the nanocrystalline Fe_73.5Cu₁Mo₃Si_13.5B₉ alloys at the as-cast state and the anneals at various temperatures. The results of measurements demonstrate the co-existence of the α-Fe(Si) nanocrystalline phase and interficial amorphous phase in the crystallized alloys. The variations of the hyperfine field and relative areas of these phases with the annealing temperature are attributed to the annealing-induced diffusion of Cu,Mo, B and their redistributions in these phases.30 percent of iron contained in the amorphous phase was found and this state of affairs corresponds to the best magnetic properties. The two-phase, disordered anisotropy model makes clear, that a certain amount of amorphous phase was essential to the excellent soft magnetic properties of nanocrystalline alloys. The deterioration of the properties is due to the existence of Fe₂B phase .