Lajos K. Varga

Research Institute of Solid State Physics and Optics of

Hungarian Academy of Sciences

Proposal full title:

Amorphous Metal-Insulator type soft magnetic composites 

  

Proposal acronym: AMINMAGDate of preparation: 10.09.2004 

Type of Instrument STREP (Specific Targeted Research project) Submission stage: OUTLINE proposal 

Activity code addressed: NEST-2003-1 ADVENTURE 

Duration of the project: 36 months

(FeSi, FeAl, permalloy) commercialized 100 years ago (Mn-Zn and Ni-Zn ferrites) commercialized 50 years ago amorphous alloys 25 years ago nanocrystalline alloys about 10 years ago

Limitations: eddy current losses - metals low temperature limit – ferrites

Solution: a metal - insulator nanocomposite -metaferrite

Adventure: to prove the theoretical prediction:

The exchange interaction can be replaced by the extended dipolar interaction in averaging out the local anisotropies and so producing a soft magnetic material.

.16

3/4

0

22

xDJ

A sd

.111

63/1

641

4

6

damcr

effAA

x

ADKxK

K1 ~ (8-48) 103 J/m3

<K> ~ 1-10 J/m3

Experimental techniques:

1. Gas atomizing ferromagnetic bulk amorphous alloy (FBA)+ Coating with Mg or Zn by vapor deposition and oxidation of Mg or Zn. + Compaction between Tg and Tx.

2. Spray forming of FBA with ZrO or Al2O33. Plasma spray of FBA with ZrO or Al2O34. Preparation of composite oxides (e.g. Fe(Co)-M-O, where

M = Al, Zn, or Si) by mechanical milling + cold compaction+ sintering and precipitation of nanosized Fe(Co) particles by subsequent heat treatment

5. Reduction of Fe(Co) nanosized oxide powder in H2 fluidizing bed+Coating with Mg or Zn by vapor deposition and oxidation of Mg or Zn+compaction by hot isostatic pressure

AbstractBad:

The project proposed aims to explore the concept of novel metal-insulator composite materials consisting of the “active” amorphous magnetic particles embedded in a host insulator matrix, which are expected to exhibit excellent soft magnetic properties both at high-frequencies (up to 1 GHz) and at high temperatures (up to 300-400 oC), thus meeting the needs of modern telecommunication systems and power electronics.

Good:

The proposal aims to realize a scientific and technological break-through in the field of high frequency and high temperature soft magnetic materials developing a new meta- material consisting of the “active” amorphous magnetic particles embedded in a host insulator matrix making possible new applications in informatics and power electronics at high-frequencies (up to 1 GHz) and at high temperatures (up to 300-400 oC.

Bad:

No interdisciplinarity

No industrial partner

No prediction of the economical benefit