DIANET

DIANET

SII propose three merits

A Global Market Leader of Rotor Magnet for Watches

We, Seiko Instruments Inc., propose three merits of our samarium cobalt magnet.
Seiko Instruments’ samarium cobalt magnet guarantees a high quality design, and contributes to differentiate your products from other manufacturers’ products.

1. Superior Heat Resistance

The Curie temperature (Tc)* of our samarium cobalt (Sm Co) magnet is higher than 800 deg-C. This superior heat resistance enables reflow soldering for mounting process.

Heat-demagnetization graph comparing SmCo and NdFeB magnets up to 300°C. While SmCo (blue line) remains stable at nearly 0% loss, NdFeB (orange line) demagnetizes sharply after 150°C, reaching -100%. This highlights the superior heat resistance of SII's SmCo magnets (Tc > 800°C), making them ideal for reflow soldering

* Curie temperature: The temperature at which a ferromagnetic substance becomes paramagnetic on heating.
Heat-Demagnetizing factor varies, depending on usage environment and conditions. This does not guarantee heatresistant temperature.

2. Small Dispersion of Magnetic Characteristics

Seiko Instruments has successfully created its innovative processing technology in order to minimize dispersion of magnetic characteristics.

▶︎ Precision processing technology : Dimensional tolerance in microns
▶︎ Powder controlling technology : Minimization in dispersion of magnetic characteristics
A bell curve graph comparing FLUX value dispersion between SII and conventional processing. The blue curve (SII unique processing) is tall and narrow, showing minimal variation and high consistency. The orange curve (conventional) is wider and flatter, indicating higher quality dispersion. This proves SII’s precision through advanced powder controlling technology

3. Applicable for a different variety of Size and Configuration

Seiko Instruments is a global market leader of rotor magnets for watches. The innovative technology and experience in successfully developing and manufacturing rotor magnets promise to meet your requirements.

A two-panel image showcasing SII's miniaturization: The left graph highlights their specialty in compact magnets (under 10mm width / 3.5mm height). The right 3D view of a wristwatch movement shows a DIANET 'Rotor Magnet' in situ, demonstrating high-precision application in micro-machinery

* Contact the sales office to discuss for different sizes.

Please contact us for more details.