A (Permalloy + NiZn Ferrite) Moldable Magnetic Composite for Heterogeneous Integration of Power Electronics.

Chao Ding,Khai D T Ngo,Guoquan Lu,Yunhui Mei

doi:10.3390/ma12121999

Abstract

Soft magnetic moldable composites (SM2Cs) would be ideally suited for the integration of magnetic components in power electronic converters because they can be formed into magnetic cores by low-temperature and pressure-less processing. However, most SM2Cs have low relative magnetic permeability, typically less than 30, and high core-loss densities at switching frequencies over 1 MHz. To improve their magnetic properties, we combine powders of Permalloy and a NiZn ferrite with an acrylic polymer to formulate a paste of SM2C. The paste can be molded and then cured below 200 °C without pressure to form cores with a relative permeability over 35 and a core-loss density at 1 MHz, 30% lower than those of commercial cores. The ease of its processing and high-performance properties makes the SM2C a good candidate material for the integration of power magnetics.

Highlights

Integration of magnetic components in the manufacturing of power electronic converters has the potential to increase converter power density and efficiency at a lower cost [1,2,3,4]
soft magnetic moldable composite (SM2 C) consist of magnetic powders in a polymer that can be formed into various shapes by molding or casting and curing at a low temperature without external compaction pressure
The fabricated cores had relative permeabilities over 35 and core-loss densities comparable to, or 30% lower than that of a commercial iron-powder core with the same relative permeability, but required hot-pressing to produce

Summary

Introduction

Integration of magnetic components in the manufacturing of power electronic converters has the potential to increase converter power density and efficiency at a lower cost [1,2,3,4]. Due to their low-temperature and pressure-less processability, soft magnetic moldable composites (SM2 Cs) would be the materials of choice to simplify the integration effort [5,6,7,8]. To realize this vision, magnetic properties of the existing SM2 Cs have to be improved to have relative permeabilities over 30 and core-loss densities comparable to commercial iron-power cores for switching frequencies into the MHz range

Methods

Discussion

Conclusion