Soft magnetic amorphous alloys and their derivatives

With the rapid development of information technology including artificial intelligence, the issue related to power consumption of current electrical and electronic devices has become increasingly serious. Hence, there is a pressing need to design and develop high-performance materials that can meet the critical demands for low power consumption and high energy conversion efficiency. Soft magnetic amorphous alloys (SMAAs) and their derivatives, mainly including soft magnetic nanocrystalline alloys (SMNAs), are nowadays state-of-the-art energy-saving materials due to their high permeability (μ), low coercivity (H_c), low saturation magnetostriction (λ_s) and high saturation magnetic induction (B_s), which result in low core loss and high energy conversion efficiency, particularly for high-frequency applications. Over the past few decades, compositional design, structural modification and subsequent process control have been utilized to enhance B_s, increase μ, reduce H_c and decrease λ_s. Through a comprehensive survey on these results in literature, this review article aims to clarify the key factors influencing the soft magnetic properties of SMAAs/SMNAs from both experimental and theoretical viewpoints and further uncover the mechanisms underlying the correlations among composition, structure, processing and properties as well as their coupling effects. In addition, the current industrial application status of SMAAs/SMNAs is summarized together with the related technological challenges that impede their potential applications. To sustain the rapid development of SMAAs/SMNAs, new perspectives are also proposed for making possible breakthroughs in their soft magnetic properties and cost performance, which may trigger new research realm and further extend their application range.