Magnetization method for long high-Tc bulk superconductors used for magnetic separation

Noriyo Nishijima, Norihide Saho, Katsuhiko Asano, Hidemi Hayashi, Katsuya Tsutsumi, Masato Murakami

Research output: Contribution to journalConference articlepeer-review

14 Citations (Scopus)


We have developed a new water-treatment system consisting of a membrane separator and a magnetic separator that uses long (>200 mm) high-temperature bulk superconductors (SCs) as permanent magnets. For magnetizing the long bulk SCs, we developed a new magnetization method. Namely, a field is applied, the bulk SCs are cooled below their transition temperature (Tc), and during cooling, the bulk SCs are inserted into and withdrawn from the applied field repeatedly. As a result, the bulk SCs experience high and low fields under a gradually cooled ambient, and the trapped field gradually increases. The benefit of this method is that it can magnetize large bulk SCs by using a small field magnet. We fabricated an embedded-SC bulk magnet more than 200-mm long, and magnetized it by split-solenoid superconducting magnets with a diameter of approximately 100 mm. Field measurements showed that the developed method can magnetize a wider area over the bulk SCs than that possible with a conventional field-cooling method.

Original languageEnglish
Pages (from-to)1580-1583
Number of pages4
JournalIEEE Transactions on Applied Superconductivity
Issue number2 II
Publication statusPublished - 2003 Jun
Externally publishedYes
Event2002 Applied Superconductivity Conference - Houston, TX, United States
Duration: 2002 Aug 42002 Aug 9


  • High-temperature superconductor
  • Magnetic field
  • Magnetic separation
  • Magnetization process

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Magnetization method for long high-Tc bulk superconductors used for magnetic separation'. Together they form a unique fingerprint.

Cite this