STRESS-MAGNETIC PROPERTIES OF TbFeCo FILM AND SmFe FILM

Hiroyuki Wakiwaka – Toshiyuki Takeuchi – Kunihisa Tashiro
– Teruo Kiyomiya – Mika Makimura

   Giant magnetostrictive materials are used in the creation of actuators. These giant magnetostrictive materials are also useful as sensor materials. TbFeCo is a giant magnetostrictive material with a positive magnetostriction coefficient and grows by approximately +1,200ppm in a magnetic field of 80kA/m. On the other hand, SmFe has the negative magnetostrictive coefficient, and is shortened by -800 ppm. This paper describes the following contents. To create micro and high-sensitivity force sensors using these materials, each thin film is made using the DC magnetron sputtering method. Stress is then applied to the thin film by the bending method. While stress is applied to the thin film, the changes in the magnetic characteristics are measured using VSM. Finally, the resulting data are shown and discussed.

Keywords: giant magnetostrictive thin film, TbFeCo film, SmFe film, differential permeability, stress

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