Fe-Cu-Nb-Si—B纳米晶合金的有效磁各向异性随退火温度的变化

ANNEALING TEMPERATURE DEPENDENCE OF EFFECTIVE MAGNETIC ANISOTROPY OF Fe-Cu-Nb-Si-B NANOCRYSTALLINE ALLOYS

研究了经不同退火温度处理的Fe(?)Cu_2Nb_3Si_(?)B,纳米晶合金的有效磁各向异性〈k〉的变化,得出该合金在T_a=480—550℃之间退火后的有效磁各向异性〈k〉比相应成份的α-Fe(Si)固溶体晶粒的磁晶各向异性K_1小一个数量级,但随T_a的开高有效磁各向异性〈k〉只稍有变大,为860—910 J.m^(-1),而起始磁导率在T_a=550℃时达到最大值.这一软磁性能的改善主要是由合金的磁致伸缩系数λ_(?)的明显变小造成的,而与有效磁各向异性〈k〉的变化无关.

The effective magnetic anisotropy <K> of Fe73.5Cu1Nb3Si13.5B9 nanocrystalline alloys obtained by annealing at different temperatures has been studied. The results show that the effective magnetic anisotropy <K> of the alloys annealed at T3= 480-550℃ is of one order of magnitude smaller than that of individual α-Fe(Si) crystallites with the same Si content. With increasing Ta, the effective magnetic anisotropy becomes a little large from 860 to 910J·m-3, and the initial permeability reaches a maximum value at Ta ?550℃. This improvement of soft magnetic properties mainly results from the largely decrease of saturation magnetostriction 1, of the alloy and has nothing to do with the variation of the effective magnetic anisotropy in this region.