Effect of the partial substitution of FeCo by Ge on the magnetic properties of nanocrystalline (Fe0.8Co0.2)72.7Al0.8Si17.5Nb3Cu1B5 alloy

• Published in: Journal of non-crystalline solids 2019-10, Vol.522, p.119555, Article 119555
• Main Authors: Li, Xian-hua, Wang, Zhi, Duan, Hong-jun
• Format: Article
• Language: English
• Subjects: FeCo-based nanocrystalline materials; Microstructure; Soft magnetic properties
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2019.119555

Nanocrystalline soft magnetic ribbons, with a composition of (Fe0.8Co0.2)72.7-xAl0.8Si17.5Nb3Cu1B5Gex (x = 0, 0.5, 1), were synthesized by melt spinning and subsequent crystallization. Special attention was focused on the microstructure, crystallization process and initial permeability. The crystallization process and microstructure were examined by using differential scanning calorimetry and X-ray diffractometry, respectively. The temperature dependence of initial permeability was presented in combination with the effect of the Ge substitutions. As a result, the Curie temperature of amorphous (Fe0.8Co0.2)72.7Al0.8Si17.5Nb3Cu1B5 alloy was enhanced by Ge addition, which implied improved soft magnetic properties at elevated temperatures. The (Fe0.8Co0.2)71.7Al0.8Si17.5Nb3Cu1B5Ge1 alloy annealed at 640 °C for 0.5 h exhibited superior magnetic softness at room- and high-temperatures with respect to the Ge-free alloy. •The effect of adding Ge into FeCo based alloys was investigated.•Ge addition increases the Curie temperature of amorphous alloy.•The FeCoAlSiNbCuBGe alloys exhibit excellent high-temperature magnetic softness.•The optimum nanocrystalized temperature is 640 °C for 0.5 h in vacuum.