Fe₇₃Si₁₅Nb₃B₈Cu₁铁芯薄带的热处理工艺研究

Study on Heat Treatment Process of Fe₇₃Si₁₅Nb₃B₈Cu₁ Core Ribbons

摘要:

本文对用Finemet型Fe73Si15Nb3B8Cu1快淬薄带制备的铁芯增加预退火处理，再在540 oC晶化退火处理得到退火铁芯。结果表明，随着预退火温度提高，预退火的薄带及再经晶化退火的薄带的韧性均逐渐降低，预退火后非晶薄带的第一晶化温度变化不大，而第二晶化峰值温度向高温方向偏移，预退火扩大了非晶薄带晶化退火的温度范围，有利于获得性能更加稳定的非晶纳米晶薄带；增加预退火处理的薄带的晶粒尺寸比直接晶化退火薄带的晶粒分布更均匀，其中在450 oC预退火的薄带经晶化退火后，晶粒尺寸在8~15 nm之间。增加预退火的铁芯样品，其振幅磁导率和铁损较直接退火的均有明显改善，其中经450 oC预退火的铁芯具有最大的振幅磁导率（μa=8.6×104, f=10 kHz）和最小的交流铁损（P0.5/10k=8.7 W/kg），分别较直接退火的铁芯升高了16.0%，下降了17.1%。

Abstract:

Finemet-type Fe73Si15Nb3B8Cu1 ribbon cores were prepared through adding pre-annealed treatment before crystallization annealing at 540 oC. It is found that, with an increase of pre-annealing temperature, the toughness of the pre-annealed and final crystallization annealed ribbons gradually decreased; and the second crystallization peak temperature shifted toward the higher temperature, although the difference among the first crystallization temperatures of the amorphous ribbons by pre-annealing treatment at different temperatures was not obvious. Namely, the pre-annealing expanded the crystallization annealing temperature range for the amorphous ribbon, which was beneficial to obtaining more stable and high performance amorphous nanocrystalline ribbons. The grain size of the additional pre-annealed ribbons was more uniform than that of the direct crystallization annealing ribbons, which was in the range of 8~15 nm for the ribbons by additional pre-annealing at 450 °C. The amplitude permeability and iron loss of iron cores with pre-annealing treatment had significantly improved compared with direct annealing samples, particularly, the cores pre-annealed at 450 oC had the largest amplitude magnetic permeability (μa=8.6×104, f=10 kHz) and the smallest AC core loss (P0.5/10k=8.7 W/kg), which were increased 16.0% and decreased 17.1% compared with directly annealing cores, respectively.