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Title: 0‐3 magnetic nanocomposites via EPD: Current status for power component fabrication and future directions

Inductors and transformers (here referred to as power components) for modern AC/DC switching power supplies require magnetic materials that have high power density and efficiency at high frequencies, with high magnetic saturation, low coercivity, and multi‐micrometer thicknesses to increase magnetic energy storage and power handling. Rather than using a single‐phase magnetic material in a polymer‐based composite, a composite formed from two magnetic phases (such as a 0‐3 nanocomposite) can simultaneously achieve all of the listed requirements and benefit from contributions by both the zero‐ and three‐dimensional phases to the magnetic properties. The fabrication of 0‐3 magnetic nanocomposites for power component applications requires a method to deposit magnetic nanoparticles into thick, physically stable yet porous films, and a subsequent method for infiltrating the magnetic nanoparticle film with another magnetic material. Here, the deposition of magnetic nanoparticles into micron‐thick films using electrophoretic deposition (EPD) is discussed. This is described along with a new method, to improve upon traditional EPD methods by increasing film–substrate interactions with chelating agents, therefore increasing film stability. Next, the use of electro‐infiltration for fully incorporating a secondary magnetic material within the nanoparticle film is presented, showing the cumulative fabrication process with the addition of a multilayered nanocomposite fabrication technique for increasing overall nanocomposite thickness. The subsequent cross‐sectional and magnetic characterization of the fabricated 0‐3 nanocomposites is also shown. Finally, future directions for 0‐3 magnetic nanocomposites are offered, with emphasis on potential materials synthesis techniques and on translating knowledge beyond power component applications.

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Author(s) / Creator(s):
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Publisher / Repository:
Date Published:
Journal Name:
Journal of the American Ceramic Society
Medium: X Size: p. 1859-1870
["p. 1859-1870"]
Sponsoring Org:
National Science Foundation
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