Tdk Corporation

Atsuhito Matsukawa

Hideharu Moro

Katsuhiko Wakayama

Yoshihito Hirai

Takuya Aoki

Naoyoshi Sato

Ryuichi Wada

Kensaku Asakura

Shoji Inoue

Yoshihiro Honjo

Mitsuhiro Matsuhashi

Toshihisa Murayoshi

Hideharu Moru

A magnetic sheet comprises, by vol. %, Fe&#x2014;Si&#x2014;Al alloy flat powder: 36% or more. The Fe&#x2014;Si&#x2014;Al alloy flat powder comprises, by wt %, 9.3%&#x2264;Si&#x2264;9.7%, 5.7%&#x2264;Al&#x2264;6.1%, and remaining Fe. The Fe&#x2014;Si&#x2014;Al alloy flat powder has: an aspect ratio in a range of 20 or more and 50 or less; a 50% particle size Din a range of 50 &#x3bc;m or more and 100 &#x3bc;m or less; and a coercivity Hc of 60 A/m or less. The magnetic sheet has a temperature characteristic of permeability &#x3bc;' measured at 1 MHz exhibiting a maximum value in a range of 0&#xb0; C. or more and 40&#xb0; C. or less.

High permeability magnetic sheet

A flat soft magnetic material to be used for a noise-suppressing magnetic sheet, wherein the 50% particle size D(&#x3bc;m), coercive force Hc (A/m) and bulk density BD (Mg/m) of the flat soft magnetic material satisfy the following formula (1)./(&#xd7;BD)&#x2267;1.5&#x2003;&#x2003;(1)

Flat soft magnetic material and process for its production

The performance index &#x3bc;'&#xd7;Q of a magnetic core member, in which an Fe&#x2014;Si&#x2014;Cr alloy is used, is further improved. A flaky soft magnetic metal powder, which is used in a magnetic core member for an RFID antenna comprising the above flaky soft magnetic metal powder and a binder, wherein it is composed of an Fe&#x2014;Si&#x2014;Cr alloy having an Ms (saturation magnetization)/Hc (coercive force) of 0.8 to 1.5 (mT/Am) in an applied magnetic field of 398 kA/m. In the present invention, it is preferable that the flaky soft magnetic metal powder consists of 7 to 23 at % of Si, 15 at % or less of Cr (excluding 0), and the balance being Fe and inevitable impurities, and that it has a weight-average particle size Dof 5 to 30 &#x3bc;m and an average thickness of 0.1 to 1 &#x3bc;m.

Flaky soft magnetic metal powder and magnetic core member for RFID antenna

A ferrite material of the present invention is configured such that 0.05 to 1.0 wt % of bismuth oxide in terms of BiO, 0.5 to 3.0 wt % of tin oxide in terms of SnO, and 30 to 5000 wt ppm of chromium oxide in terms of CrOare added to a predetermined main component mixture composition. Therefore, it is possible to achieve an improvement in DC bias characteristics, an improvement in temperature characteristics of initial magnetic permeability, and an improvement in resistivity and further achieve an improvement in burned body strength, particularly in burned body flexural strength (bending strength).

Ferrite material and electronic component using the same

Manganese-zinc system ferrite

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Tokyo, Japan

Atsuhito Matsukawa