Preparation of gas-atomised amorphous soft magnetic powders with high saturated magnetisation above 1.25 T realised by senary Fe₇₃Si_9−xB₁₀P₅C₃Mo_x alloys with abnormal glass-forming ability

ABSTRACT

Micron-scale powdered amorphous soft magnetic materials are highly pursued for miniaturised and high-efficiency power inductors working at high frequencies due to their excellent soft magnetic properties such as extremely low coercivity and high electrical resistivity originated from the disordered atomic structures and zero magnetocrystalline anisotropy. However, the limited glass-forming ability (GFA) of amorphous soft magnetic alloys has hindered the preparation of amorphous soft magnetic powders through gas atomisation. Here, we present the development of amorphous soft magnetic alloys based on Mo-containing alloys with abnormal GFA, and demonstrate preparation of fully amorphous soft magnetic powders fabricated through the conventional medium-cooling-rate gas atomisation process. Our Mo-containing Fe₇₃Si_9−xB₁₀P₅C₃Mo_x alloy showed fully amorphous state in a ribbon form with thickness up to 179 μm. Gas atomisation performed using the alloy produced fully amorphous powder with diameter up to 75 μm, while possessing high saturation magnetisation of 1.25 T.

KEYWORDS:

• Amorphous
• soft magnetic
• soft magnetic powder
• gas atomisation
• magnetic core

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This study was supported financially by the Fundamental Research Program (development of technical self-reliance, high-performance and high-added value magnetic powder materials) of the Korea Institute of Materials Science (KIMS), and by the Civil–Military Technology Cooperation Program [grant number 18-CM-MA-15] of Defense Acquisition Program Administration.

Notes on contributors

Yeong Gyun Nam

Yeong Gyun Nam Ph.D. Candidate student of school of materials science and engineering, Pusan National University.

Kyoung-Hoon Bae

Kyoung- Hoon Bae Ph.D., Post-doctoral researcher, Korea Institute of Materials Science.

Hearan Kim

Hearan Kim Intern researcher, Korea Institute of Materials Science.

Sangsun Yang

Sangsun Yang Ph.D., Principle Researcher of Korea Institute of Materials Science.

Yong-Jin Kim

Yong-Jin Kim Ph.D., Principle Researcher of Korea Institute of Materials Science.

Jung Woo Lee

Jung Woo Lee Ph.D., Assistant professor, school of materials science and engineering, Pusan National University.

Jae Won Jeong

Jae Won Jeong Ph.D., Senior Researcher Researcher, Korea Institute of Materials Science.