Finemet合金核外电子相互作用的多普勒展宽谱

Extranuclear Electron Interaction of Finemet Alloy Studied by Using Doppler Broadening Spectrum of Positron Annihilation

摘要:

采用双高纯锗探头符合的正电子湮没辐射多普勒展宽谱测量了Finemet合金各组元的商谱以及在350,380,400 ℃下退火(10 min)的Finemet非晶薄带的商谱,对Finemet合金热处理过程中元素核外电子间的相互作用进行了研究.结果表明,Finemet合金淬火态商谱的谱峰比纯金属元素Fe,Cu,Nb的谱峰要低,Fe和Nb之间存在着3d4d轨道键合作用.随着退火温度的升高,Fe原子的3d电子与Nb原子的4d电子之间的轨道键合作用增强,商谱谱峰降低,Cu原子易在表面富集,而Nb原子则在非晶薄带中富Fe区域里重新分布.

Abstract:

The ratio curves of Finemet alloy elements and Finemet amorphous ribbons(annealed at 350 ℃,380 ℃ and 400 ℃ for 10min respectively)were measured with the Doppler broadening spectrum of positron annihilation which adopted two HPGe detector coincidence technique to investigate the extranuclear electron interaction during annealing process.Results show that the peaks of asquenched Finemet ribbons is relatively low after a comparison with the ratio curves of pure elements Nb,Fe and Cu.There exists a bonding between 3d orbit electrons in Fe atoms and 4d orbit electrons in Nb atoms.The bonding become more strengthened with the increment of annealing temperature,which leads the peaks of ratio curves to decrease.Meanwhile,the Cu atoms tend to be enriched in the surface and the Nb atoms redistribute to the amorphous layer of ribbon where the Fe atoms are rich.