Critical state-induced emergence of superior magnetic performances in an iron-based amorphous soft magnetic composite
Liliang Shao, Rongsheng Bai, Yanxue Wu, Jing Zhou, Xing Tong, Hailong Peng, Tao Liang, Zongzhen Li, Qiaoshi Zeng, Bo Zhang, Haibo Ke, Weihua Wang
Abstract
Abstract Soft magnetic composites (SMCs) play a pivotal role in the development of high-frequency, miniaturization and complex forming of modern electronics. However, they usually suffer from a trade-off between high magnetization and good magnetic softness (high permeability and low core loss). In this work, utilizing the order modulation strategy, a critical state in a FeSiBCCr amorphous soft magnetic composite (ASMC), consisting of massive crystal-like orders (CLOs, ∼1 nm in size) with the feature of α -Fe, is designed. This critical-state structure endows the amorphous powder with the enhanced ferromagnetic exchange interactions and the optimized magnetic domains with uniform orientation and fewer micro-vortex dots. Superior comprehensive soft magnetic properties at high frequency emerge in the ASMC, such as a high saturation magnetization ( M s ) of 170 emu g −1 and effective permeability ( μ e ) of 65 combined with a core loss ( P cv ) as low as 70 mW cm −3 (0.01 T, 1 MHz). This study provides a new strategy for the development of high-frequency ASMCs, possessing suitable comprehensive soft magnetic performance to match the requirements of the modern magnetic devices used in the third-generation semiconductors and new energy fields.